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Title:
Community structure, faunal distribution, and environmental forcing of the extinction of marine molluscs in the Pliocene San Joaquin Basin, Central California
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Bowersox, John Richard
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Neogene
Chronostratigraphy
Paleoecology
Multivariate statistics
Diversity
Dissertations, Academic -- Geology -- Doctoral -- USF
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non-fiction   ( marcgt )

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Abstract:
ABSTRACT: This study focuses on reconstructing the dynamics within the Pliocene San Joaquin Basin (SJB) molluscan fauna. This was accomplished by 'binning' the data within a constrained chronostratigraphic framework into: 1) 484 individual stratigraphically-ordered locality collections; 2.) 116 stratigraphically-sequential compiled ten-meter sample intervals; 3.) 15 intervals compiled by 4th-order eustatic cycles; 4.) three formation-level compiled samples; and 5.) the Etchegoin group fauna (informal San Joaquin Basin nomenclature) overall. These datasets were analyzed by inferential, multivariate, and descriptive statistics to examine local and regional environmental controls on faunal composition, community associations and distributions; cross-scale faunal structure; and large-scale environmental controls on immigration, diversity, and extinction. Primary environmental controls on community composition and spatial distribution were substrate type and water paleo-depth.^ ^Consequently, the Pliocene SJB record is one of a temporal succession of complexly distributed habitats and species. Regional habitat patchiness controlled individual locality-level (a1) diversity and contributed 62% of regional sample-level (a2) diversity. Endemic species comprise 30% of the fauna but account for 42% of a2 diversity, indicative of their environmental sensitivity. Partitioning a2 diversity between non-endemic and endemic species reveals habitats segmented as shared or available solely to endemic species. At the level of 4th-order eustatic variations, diversity between temporal samples (b1) accounts for ~80% of total (y) diversity consistent with eustatic control of faunal structure. During eustatic fluctuations, endemic habitats expanded and contracted at rates greater than shared habitats. Invading species quickly filled shared habitat during transgression and displaced endemic species during regression.^ ^Therefore, climatic- and regression-driven hydrologic change and productivity collapse in the Pliocene SJB led to seven extinctions of >40% species. Peak faunal diversity corresponded to periods of highest sea-levels whereas low-diversity faunas characterized low to rising sea levels. Thus, speciation events following extinctions suggest diversification of surviving faunas into habitats newly-created by changed environmental conditions.The broader implication of this study is that during current global sea level rise depleted endemic faunas of shallow-coastal and ocean-marginal environments will be displaced into the shared-habitat with consequent extinction likely if adaptation does not keep pace with environmental change.
Thesis:
Dissertation (Ph.D.)--University of South Florida, 2006.
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Includes bibliographical references.
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by John Richard Bowersox.
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Community Structure, Faunal Distribution, and Envir onmental Forcing of the Extinction of Marine Molluscs in the Pliocene San Joaquin Basi n, Central California by John Richard Bowersox A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy Department of Geology College of Arts and Sciences University of South Florida Major Professor: Peter J. Harries, Ph. D. Eric A. Oches, Ph. D. Gregory S. Herbert, Ph. D. Jonathan G. Wynn, Ph.D.John M. Lawrence, Ph.D. Date of Approval: October 13, 2006 Keywords: Neogene, chronostratigraphy, paleoecology multivariate statistics, diversity Copyright 2006, John Richard Bowersox

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Dedication To my wife, Trish Bowersox. This has been a long, strange trip but it is finally at its end. Thank you so much for your forbearance.

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Acknowledgments I wish to thank the many people and organizations w ho supported my research. My daughters Alexandra Bowersox, Bakersfield, Calif ornia, and Morgana Bowersox, Knoxville, Tennessee, were my assistants 1999-2004 for most of the 27 days of field work. Without their help I would never have accomp lished the number of locality visits and collections that went into this project. My mo ther, Leona Bowersox, Florissant, Colorado, contributed both financial and spiritual support for which I will ever be grateful. This dissertation is completed in time f or her 80th birthday. Many thanks to my committee members and their contr ibutions, guidance, and support through this process: Peter Harries, Rick O ches, Greg Herbert, Jonathan Wynn, and John Lawrence. I would especially like to than k my Major Professor Peter Harries for the many years of advice and discussion, suppor t and encouragement. Financial and research support was provided by the Geology Department of the University of South Florida and the Department of E arth and Planetary Sciences of the University of Tennessee, Knoxville. Additional fin ancial support was provided by the American Geophysical Union, 2004 Western Pacific Ge ophysics Meeting Student Travel Grant; University of South Florida Geology Alumni S ociety, Richard C. Davis Endowed Fellowship Award, 2004; University of South Florida Tharp Endowed Award, 2000, 2001, 2002, 2003, 2004; Sigma Xi, Grant in Aid of R esearch, 2000; and the Tampa Bay Fossil Club Scholarship, 1999. Access to the Kettleman Hills North Dome oil field was granted by J.P. Oil Company, Bakersfield and Avenal, California. Acces s to the Muddy Creek locality was granted by The Wildlands Conservancy, Wind Wolves P reserve, Maricopa, California. Access to Tar Canyon was granted by Hewitson Farms, Avenal, California; my thanks to the Kings County, California, Sheriff’s office in A venal for this contact.

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i Table of Contents List of Figures v List of Tables x Abstract xi Chapter 1:Introduction 1 The Coalinga Region 1 Purpose 1 Paleoenvironmental Setting 3 Geologic Setting 3 Paleogeography 5 Paleoceanographic Setting 5 Chronostratigraphy 6 Methodology 7 Paleontological Methods and Data Preparation8Taxonomy and Ecology 10 Taphonomy 11 Analysis of Faunal Composition 12 Statistical Analysis 13 Contents of Appendices 18 Appendix A 18 Appendix B 19 Appendix C 19 Appendix D 19 Appendix E 19 Appendix F 20 Appendix G 20 References 20

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ii Chapter 2:Chronostratigraphic Framework of the Plio cene Etchegoin Group, San Joaquin Basin, Central California28 Abstract 28 Introduction and Previous Work 29 Etchegoin Group Stratigraphy 29 Provincial Molluscan Stages 34 Age of the Base of the Tulare Formation38 Late Neogene Biostratigraphy of the SJB 39Sr Isotopic Numerical Age Dates 42 Tephrachronologic and Numerical Age Dates43Discussion 45 Conclusions 48 References 48 Chapter 3:Late Neogene Paleobathymetry, Relative Se a Level, and Basin Margin Subsidence, Northwest San Joaquin Basin, Cal ifornia57 Abstract 57 Publication Citation 57 Late Neogene Paleogeography and Paleobathymetry of the San Joaquin Basin 58 Northwest San Joaquin Basin Relative Sea Level and Basin Margin Subsidence 58 Discussion 63 References 63 Chapter 4:Multivariate Community and Environmental Analysis of Molluscs from the Pliocene Etchegoin Group, Central Californ ia66 Abstract 66 Introduction 66 Geologic Setting and Paleogeography72 Methodology 72 Statistical Analysis 75 Multivariate Statistical Analysis 83 Effective Temperature 84 Results 85 Discussion 97 Environmental Controls on Faunal Distributions102Community Distributions 104 Conclusions 115 References 116

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iii Chapter 5:Cross-Scale Temporal and Spatial Diversit y and Structure of Molluscan Faunas from the Pliocene Etchegoin Group, Central California 124 Abstract 124 Introduction and Previous Work 125 Methodology 126 Statistical Analysis 132 Results 138 Discussion 142 Temporal and Spatial Scaling of Diversity143Scaling Endemic Fauna Diversity 148 Eustatic Control of Diversity 155 Comparison of SJB and Central Coastal California Pl iocene and Modern Faunas 158 Applicability of Diversity Indices 161 Implications for Ancient and Modern Marginal Ocean Basins162 Conclusions 167 References 169 Chapter 6:Reassessment of Extinction Patterns of Pl iocene Molluscs from California and Environmental Forcing of Extinction in the San Joaquin Basin 175 Abstract 175 Publication Citation 176 Introduction and Previous Work 176 Methodology 177 Etchegoin Group Stratigraphy and Faunal Data Set184 Results 185 Discussion 191 Pliocene SJB Paleogeography and Marine Paleoenviron mental Variability 192 Paleosalinity and Paleotemperature195Circulation, Upwelling, and Productivity198Extinction in the Pliocene San Joaquin Basin200Biogeography of California Late Neogene Molluscan F aunas207 Conclusions 214 References 214

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iv Appendix A:Localities Catalog 226 Appendix B:Catalog of the Late Neogene Molluscs fro m the Coalinga Region, Fresno and Kings Counties, California (Sant a Margarita Formation and Etchegoin Group): Part 1: P late References 251 Appendix C:Table of Faunal Locality Data from This Study277 Appendix D:Multivariate Analysis of Etchegoin Group Faunas318 Appendix E:Multivariate Analysis, ET, and Diversity Indices Table364 Appendix F:Diversity Analysis Table379Appendix G:40Ar/39Ar Analysis of Two Etchegoin Group Tuffs384 About the Author End Page

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v List of Figures Figure 1.1Early Pliocene paleogeography of central California at ~5 Ma (modified with annotations from Bowersox, 2004a).2 Figure 1.2 Composite Pliocene stratigraphic and 4th-order relative-sea-level curve. 4 Figure 1.3Outcrop area of marine Etchegoin group st ratigraphic intervals corresponding to the fauna zonule of Adegoke (1969) and the number of localities per interval. 14 Figure 1.4. Species richness and occurrences in lo cality collections. 15 Figure 1.5Test for under-represented species in the Etchegoin group fauna.16 Figure 2.1. Early Pliocene paleogeography of centr al California at ~5 Ma (modified with annotations from Bowersox, 2004).30 Figure 2.2Locations of type sections of the Etchego in Group members, the underlying Reef Ridge and Santa Margarita Formation s, and the overlying Tulare Formation in sequence by their pub lication years.31 Figure 2.3Summary of the history of lithostratigrap hic nomenclature for the late Neogene section of the SJB. 33 Figure 2.4Composite Pliocene stratigraphic and 4th-order relative-sea-level curve. 35 Figure 2.5Age spectra of tuffs from Kettleman Hills localities 030202.01b (A) and 030202.05 (B) show the effect of excess arg on and resulting old apparent ages. 44 Figure 3.1Early Pliocene paleogeography of central California at ~5 Ma.59 Figure 3.2Pliocene paleobathymetry of the SJB.60Figure 3.3Comparison of the late Neogene northwest SJB relative sealevel curve to the Gulf of Mexico eustatic curve (Wornard t and Vail, 1991; Wornardt et al., 2001). 61 Figure 3.4Time-thickness diagram for the Pliocene n orthwest SJB margin. 62 Figure 4.1Early Pliocene paleogeography of central California at ~5 Ma.67 Figure 4.2Composite stratigraphic section of the Et chegoin group and Pliocene northwest SJB 4th-order relative sea level curve.69 Figure 4.3Comparison of molluscan faunal diversity with generalized relative sea-level, paleotemperature and paleosali nity (revised from Bowersox, 2005). 70 Figure 4.4Species richness and occurrences in local ity collections.74

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vi Figure 4.5Sampling intensity and covariance of spec ies richness and number of localities. 76 Figure 4.6ADistribution of species richness of the total and endemic Etchegoin group faunas. 77 Figure 4.6BRank order occurrences of species compri sing the total and endemic faunas. 78 Figure 4.7Outcrop area of marine Etchegoin group st ratigraphic intervals corresponding to the fauna zonule of Adegoke (1969) and the number of localities per interval. 80 Figure 4.8Test for under-represented species in the Etchegoin group fauna.82 Figure 4.9Effective temperature averaged in 10 m st ratigraphic intervals. 86 Figure 4.10ASubstrate and water depths from Siphonalia zone DCA.87 Figure 4.10BSubstrate and water depths from Pecten zone DCA.88 Figure 4.10CSubstrate preferences of the frequently occurring species from Siphonalia zone DCA clusters. 89 Figure 4.11ADendrogram from the upper Etchegoin Siphonalia zone. 91 Figure 4.11BDendrogram from the upper San Joaquin Pecten zone. 92 Figure 4.12A Siphonalia zone cluster groups confirmed by NMDS. 93 Figure 4.12B Pecten zone cluster groups confirmed by NMDS.94 Figure 4.13Bathymetric ranges of Siphonalia zone ta xa (A) and method of water paleo-depth determination from DCA (B).95 Figure 4.14Paleowater depth averaged in 10 m strati graphic intervals. 98 Figure 4.15Stratigraphic distributions (A) and dist ributions by water depths (B) of communities recognized in this study.99 Figure 4.16ADistribution of communities during uppe r Etchegoin (lower interval) deposition. 106 Figure 4.16BDistribution of communities during depo sition of the uppermost Etchegoin Patinopecten zone. 106 Figure 4.16CDistribution of communities during uppe rmost Etchegoin Macoma zone deposition. 107 Figure 4.16DDistribution of communities during depo sition of the uppermost Etchegoin Siphonalia zone. 107 Figure 4.16EDistribution of communities during depo sition of the uppermost Etchegoin Pseudocardium zone.108 Figure 4.16FDistribution of communities during depo sition of the uppermost Etchegoin Littorina zone. 108 Figure 4.16GDistribution of communities during depo sition of the lower San Joaquin Cascajo Conglomerate member.109 Figure 4.16HDistribution of communities during depo sition of the lower San Joaquin Neverita zone. 109 Figure 4.16IDistribution of communities during depo sition of the upper San Joaquin Pecten zone. 110

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vii Figure 4.16JDistribution of communities during depo sition of the upper San Joaquin Trachycardium zone. 110 Figure 4.16KDistribution of communities during depo sition of the upper San Joaquin Acila zone. 111 Figure 4.16LDistribution of communities during depo sition of the upper San Joaquin Mya zone. 111 Figure 5.1Early Pliocene paleogeography of central California at ~5 Ma.127 Figure 5.2Composite stratigraphic section of the Et chegoin group and Pliocene northwest SJB 4th order relative sea level curve. 128 Figure 5.3Species richness and occurrences from 484 locality collections were compiled in 126 ten-meter sample intervals.131 Figure 5.4Sampling intensity and covariance of spec ies richness and occurrences. 133 Figure 5.5ADistribution of species richness of the total and endemic Etchegoin group faunas. 134 Figure 5.5BRank order occurrences of species compri sing the total and endemic faunas. 135 Figure 5.6Outcrop area of marine Etchegoin group st ratigraphic intervals corresponding to the fauna zonule of Adegoke (1969) and the number of localities per interval. 136 Figure 5.7Under-representation species in the Etche goin group fauna was tested by ranking the occurrences the species from the 15 stratigraphic intervals deposited during the 4th order eustatic cycles. 139 Figure 5.8Comparison of Shannon diversity for the t otal fauna diversity (HT) and the proportional contributions to HT of the non-endemic (HM) and endemic (HE) faunas and total-fauna evenness (E).140 Figure 5.9Comparison of HT and E to S tests how the occurrences of species are distributed among the species and the overall s tructure of the Etchegoin group fauna. 141 Figure 5.10The effects of temporal scaling on diver sity. 144 Figure 5.11Total Etchegoin group faunal diversity i s scaled by from 1 (locality collection) to diversity (Etchegoin group in toto ).145 Figure 5.12AComposition of the Etchegoin group faun a comprising 67% of occurrences. 146 Figure 5.12BComposition of the Etchegoin group faun a comprising 67% of occurrences. 147 Figure 5.13Regional diversity distributions from a single 10 m-sample interval from the transgressive section at the base of the Siphonalia zone. 149 Figure 5.14Contribution of endemic-fauna diversity to total diversity.151

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viii Figure 5.15AComparison of the temporal distribution s of some generalist and specialist species in the Etchegoin group non-endem ic faunas as their percent of occurrences of the total fauna.153 Figure 5.15BComparison of the temporal distribution s of some generalist and specialist species in the endemic Etchegoin group f aunas.154 Figure 5.16ATotal and endemic fauna diversity compa red to 4th order eustatic sea level and generalized paleotemperature and pale osalinity (modified from Bowersox, 2005).156 Figure 5.16BHT can be partitioned between the endemic and non-end emic contributions to demonstrate habitat exploitation.1 57 Figure 5.17AComparison of Etchegoin group diversity to diversity calculated for the Pliocene fauna from the Santa Ma ria Basin (Woodring and Bramlette, 1950).159 Figure 5.17BDiversity of modern central coastal Cal ifornia estuarine faunas.159 Figure 5.18The relationship between spatial and tem poral scaling for the Etchegoin group fauna. 163 Figure 6.1Location of latest Miocene through Late P leistocene faunas reviewed in this study. 178 Figure 6.2Correlation of the Late Neogene formation s in Central and Southern California in this study. 179 Figure 6.3Comparison of Stanley, et al (1980) with this paper of the percent of latest Miocene and Pliocene faunas surviving to the Holocene.186 Figure 6.4Percent of each latest Miocene through La te Pleistocene fauna surviving to the Holocene. 187 Figure 6.5AProportion of extant bivalve species in latest Miocene through Late Pleistocene faunas from Pacific coastal Califo rnia and the SJB of central California. 188 Figure 6.5BProportion of extant gastropod species i n the same faunas. 189 Figure 6.6Comparison of the proportion of extant sp ecies in latest Miocene through Pleistocene faunas from Pacific coastal bas ins and the SJB. 190 Figure 6.7Comparison of the proportion of extant sp ecies from Pacific coast faunas and the SJB. 193 Figure 6.8Early Pliocene paleogeography of central California at ~5 Ma (modified with annotations from Bowersox, 2004a). 1 94 Figure 6.9Comparison of molluscan faunal diversity with relative sea-level.196 Figure 6.10Diversity of molluscan faunas from the u ppermost Etchegoin Formation. 202 Figure 6.11AProportion of Etchegoin group faunas co mposed of living and extinct bivalves from coastal faunas.205 Figure 6.11BProportion of Etchegoin group faunas co mposed of living and extinct coastal fauna gastropods.206 Figure 6.12AEndemic portion of bivalve faunas. 208

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ix Figure 6.12BEndemic portion of gastropod faunas.209Figure 6.13AExtant bivalve species in Etchegoin gro up faunas and their occurrences in coastal California faunas.212 Figure 6.13BExtant gastropod species in Etchegoin g roup faunas and their occurrences in coastal California faunas.213

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x List of Tables Table 1.1Areal and stratigraphic distributions and numbers of locality collections compiled in this study.9 Table 1.2A.Test of correlation between outcrop area and the number of localities, species richness, and number of occurre nces. 17 Table 1.2BTest of correlation between the number of localities, species richness, and number of occurrences.17 Table 4.1Areal and stratigraphic distributions and numbers of locality collections compiled in this study. 73 Table 4.2ATest of correlation between outcrop area and the number of localities, species richness, and number of occurre nces. 81 Table 4.2BTest of correlation between the number of localities, species richness, and number of occurrences. 81 Table 4.3Correlation of molluscan communities deter mined in this study with previous studies. 101 Table 5.1Areal and stratigraphic distributions and numbers of locality collections compiled in this study.130 Table 5.2ATest of correlation between outcrop area and the number of localities, species richness, and number of occurre nces. 137 Table 5.2BTest of correlation between the number of localities, species richness, and number of occurrences. 137 Table 6.1.Comparison of age and percent of fauna su rviving to the Holocene using the faunas reviewed in Stanley et al .(1980) in both cases: Santa Margarita Formation (Hall, 1960, table 4); Pancho Rico Formation (Durham and Addicott, 1964); Jacalitos Formation (Nomland, 1917a); Etchegoin Glycymeris zo ne (Arnold, 1909); Cebada Sand (Woodring and Bramlette 1950); San Diego Formation (Hertlein and Grant, 1972); Mer ced Formation (Glen, 1959). 180 Table 6.2Age and percent of fauna surviving to the Holocene for faunas reviewed in this paper. 181 Table 6.3Sources of Late Neogene central and southe rn California mollusc faunas. 183 Table 6.4Extant species in correlative coastal and San Joaquin Basin faunas. 210

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xi Community Structure, Faunal Distribution, and Envir onmental Forcing of the Extinction of Marine Molluscs in the Pliocene San J oaquin Basin, Central California John Richard Bowersox ABSTRACT This study focuses on reconstructing the dynamics within the Pliocene San Joaquin Basin (SJB) molluscan fauna. This was accomplished by 'b inning' the data within a constrained chronostratigraphic framework into: 1) 484 individu al stratigraphically-ordered locality collections; 2.) 116 stratigraphically-sequential c ompiled ten-meter sample intervals; 3.) 15 intervals compiled by 4th-order eustatic cycles; 4.) three formation-level c ompiled samples; and 5.) the Etchegoin group fauna (informal San Joa quin Basin nomenclature) overall. These datasets were analyzed by inferential, multivariate and descriptive statistics to examine local and regional environmental controls on faunal compo sition, community associations and distributions; cross-scale faunal structure; and la rge-scale environmental controls on immigration, diversity, and extinction. Primary environmental controls on community composi tion and spatial distribution were substrate type and water paleo-depth. Consequ ently, the Pliocene SJB record is one of a temporal succession of complexly distributed habi tats and species. Regional habitat patchiness controlled individual locality-level (1) diversity and contributed 62% of regional sample-level (2) diversity. Endemic species comprise 30% of the f auna but account for 42% of 2 diversity, indicative of their environmental sensit ivity. Partitioning 2 diversity between non-endemic and endemic species reveals hab itats segmented as shared or available solely to endemic species. At the level of 4th-order eustatic variations, diversity between temporal samples (1) accounts for ~80% of total () diversity consistent with eustatic control of faunal structure. During eustatic fluct uations, endemic habitats expanded and contracted at rates greater than shared habitats. Invading species quickly filled shared habitat during transgression and displaced endemic species during regression. Therefore, climaticand regression-driven hydrologic change and product ivity collapse in the Pliocene SJB led to seven extinctions of >40% species. Peak faunal diversity corresponded to periods of highest sea-levels whereas low-diversity faunas cha racterized low to rising sea levels. Thus, speciation events following extinctions suggest div ersification of surviving faunas into habitats newly-created by changed environmental con ditions.

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xii The broader implication of this study is that durin g current global sea level rise depleted endemic faunas of shallow-coastal and ocea n-marginal environments will be displaced into the shared-habitat with consequent e xtinction likely if adaptation does not keep pace with environmental change.

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1 Chapter 1 Introduction The Coalinga Region The San Joaquin Basin (SJB) occupies the southern G reat Valley of California south of the subsurface Stockton Arch. It is bound ed on the west by the Diablo and Temblor ranges, on the south by the San Emidio Rang e, and on the east by the Sierra Nevada (Fig. 1.1). During the Pliocene, a marginal ocean basin occupied the southern SJB where a thick sequence of terrestrial to basina l marine clastic facies were deposited. Subsequent tectonic compression and uplift associat ed with the San Andreas Fault to the west has exposed the thick section of Pliocene Etch egoin group strata in the hills along the western and southern basin margins. The Coalin ga region, the primary area of interest of the following five studies, lies on the northwes tern margin of the SJB and extends from the White Creek Syncline on the north ~75 km so utheasterly to the Kettleman Hills South Dome and from the Coalinga Anticline ~35 km so uthwesterly to Priest Valley and includes the Jacalitos Anticline and Kreyenhagen Hi lls (Fig. 1.1). The Etchegoin group is well-exposed and fossiliferous throughout the Coali nga region. The history of geologic and paleontologic research in the SJB dates from the reports of Watts (1894) on the geology of central C alifornia and Cooper (1894) on Pliocene freshwater fossils of California. Major g eologic studies of the stratigraphy and paleontology of the late Neogene strata in the Coal inga region fall into three periods: 1905-1917, 1933-1946, and 1969 until the present. The Etchegoin group includes the Jacalitos, Etchegoin, and San Joaquin formations (W ilson, 1943; Loomis, 1990) and with the lowest portion of the overlying Tulare comprise s the Pliocene sequence in the SJB. Purpose Despite the long history of paleontologic research in the San Joaquin Basin beginning with Arnold (1909), many aspects of the p aleoecology of the Etchegoin group molluscan fauna are yet unknown. Adegoke (1969, p. 52) best stated the questions addressed in this study: The ecologic implications of the partial closure of the San Joaquin basin during the Neogene have rarely been adequately emph asized. ...It has not been possible to explain the sudden extinction of Pseudocardium densatum in the San Joaquin basin at the top of the Etchego in Formation. ...In a similar way no satisfactory explanation is known for the small number of species recorded from each formation.

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2 Figure 1.1. Early Pliocene paleogeography of central Californ ia at ~5 Ma (modified with annotations from Bowersox, 2004a). Location of the SJB with the approximate extent of the Pliocene marginal ocean basin shaded is noted o n the inset map of California. Faults west of the San Andreas fault are not shown. Locat ion of La Honda and Santa Maria Basins are shown relative to the SJB at that time. The modern shoreline and cities locations are shown for reference. Locations of Et chegoin group fossil localities are noted: A. White Creek Syncline, B. Coalinga Anticline, C. Priest Valley, D. Jacalitos Anticline, E. Kreyenhagen Hills, F. Kettleman Hills, G. Bacon Hills, H. Muddy Creek.

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3 Adegoke (1969) addressed the first question, the im plications of the partial closure of the SJB during the Pliocene, in terms of paleosalinity, nutrient supply, and paleoclimate and favored increasingly brackish conditions as the for ce driving diversity and extinction. Subsequent to Adegoke (1969), the first question ha s been addressed by Stanton and Dodd (1970), Dodd and Stanton (1975), and Loomis (1 990). Stanton and Dodd (1997) addressed the question evolution and diversificatio n within the Etchegoin group fauna. In order to understand the timing and rates of pro cesses acting on and driving changes in the Etchegoin group mollusc fauna and th e correlation of events in the SJB with regional and global events, Chapters 2 and 3 p resent a chronostratigraphic and basin evolution model for the Pliocene SJB. Three aspect s of the Etchegoin group molluscan fauna are addressed in Chapters 4 through 6: enviro nmental controls on the spatial and temporal distribution of communities, spatial and t emporal structure of the fauna, and environmental controls of molluscan extinction in t he Pliocene SJB. The following discussion introduces the Pliocene pa leoenvironments within the SJB and summarizes the methods employed in these st udies. Supplemental data, summaries of analyses, multivariate statistical plo ts, and geochronologic analysis are presented in Appendices A through G (also see discu ssion below). Paleoenvironmental Setting Changes in environmental conditions are typical of a threshold-regulated marginal basin where these variations occur abruptly and hav e dramatic consequences on the hydrologic, sedimentary, geochemical, and ecologica l systems inside the basin (Giosan, 2004). During the Pliocene, the southern SJB of ce ntral California was a marginal ocean basin connected to the Pacific Ocean through a long narrow, and shallow inlet (Fig. 1.1) and subject to profound environmental variability d riven by eustatic regression coupled with intermittent regional tectonic interruption of the connection between the SJB and the Pacific Ocean (Bowersox, 2005; Chapter 6). As a co nsequence of the limited tidal influx of marine water through the seaway, the SJB was gen erally brackish during the Pliocene except for limited periods during sea-level highsta nd when normal marine conditions prevailed. Consequent environmental deterioration during periods of eustatic regression or tectonic interruption of the connection between the SJB and the Pacific ocean led to seven major regional extinction events affecting Et chegoin group molluscan faunas. Thus, the sediments and fossils of the Pliocene Etc hegoin group (Fig. 1.2) record substantially different paleoecologic, evolutionary and paleoceanographic histories than those of nearby coastal waters. Geologic Setting The Pliocene Etchegoin group is comprised of three formations (Fig. 1.2): the Jacalitos (Arnold, 1909; Arnold and Anderson, 1910) Etchegoin (F.M. Anderson, 1905), and San Joaquin formations (Barbat and Galloway, 19 34). Woodring et al. (1940) subdivided the San Joaquin Formation into three mem bers: the basal Cascajo Conglomerate and informal lower and upper members d ivided at the base of the Pecten zone. The Etchegoin Group overlies

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4 Figure 1.2. Composite Pliocene stratigraphic and 4th-order relative-sea-level curve. Division of the San Joaquin Formation into informal lower and upper members is at the base of the upper San Joaquin Formation Pecten zone (Woodring et al., 1940). Subdivisions of the upper Etchegoin-upper San Joaqu in section from 1200-2500 m stratigraphic levels are generalized from Woodring et al. (1940).

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5 latest Miocene and earlier rocks and is overlain by the latest Pliocene-Pleistocene Tulare Formation (Fig. 1.2). Despite being situated withi n a tectonically active basin margin, the northwestern SJB remained near sea level throughout the late Neogene thus deposition of the thick ~2.4 km succession of shallow-marine to no n-marine facies Etchegoin group kept pace with basin subsidence (Bowersox, 2004; Ch apter 3). While shallow waternearshore marine deposits characterize the northwes tern margin of the Pliocene SJB, fluvial deposition dominated the eastern margin of the basin (Fig. 1.1). The coarse clastic sediments eroded from the southern Sierra Nevada an d deposited by rivers on the eastern margin of the SJB during the late Neogene consist o f poorly sorted fluvial sandstones and boulder conglomerates interbedded with siltstone an d mudstone (Bartow and Pittman, 1984). By the Late Pliocene, the Kern River delta had built out ~50 km into the SJB from the southern Sierra Nevada mountain front and inter fingered with marine facies sediments of the upper San Joaquin Formation (Dunwoody, 1986) Paleogeography The Pliocene SJB was bounded to the east by the sou thern Sierra Nevada and to the south and west by the San Emigdio and Coast Ran ges (Fig. 1.2). To the northeast, the basin was filled by late Neogene San Joaquin and Ki ngs Rivers fluvial deposits and the fan-delta Kern River Formation was deposited by the Kern River on the southeast basin margin (see Foss, 1972, Pliocene transgressive phas e map). To the northwest, the SJB opened to the Pacific Ocean through the shallow and narrow Priest Valley Strait (Loomis, 1990; Bowersox, 2005). Uplift of the southern Sier ra Nevada reached 2.5 km by 57 Ma then ceased until ~5 Ma (Wakabayashi and Sawyer, 200 1). Renewed uplift of the Kern River drainage beginning by 3.5 Ma (Clark et al., 2 005) elevated the southern Sierra Nevada above 3.5 km by 3.0 Ma (Graham et al., 1988) and led to renewed uplift along the central San Joaquin River between 2.7 and 1.4 Ma (C lark et al., 2005). Uplift of the Temblor Range and southern Coast ranges began their current phase by 5.4 Ma (Miller, 1999). Based on fault-normal convergence between t he Pacific and Sierran plates across the San Andreas fault, Argus and Gordon (2001) demo nstrated that uplift of the Coast and San Emigdio ranges probably commenced by 6.6 Ma or 8 Ma. Thus, by the Pliocene, the paleogeography of the SJB was comparable to its modern configuration. Paleoceanographic Setting The Pliocene paleoceanographic history of the SJB i s recorded in the Etchegoin group strata. The inland sea filling the Pliocene SJB was 175 km long, 100 km wide ringed by estuaries, tidal marshes, and tidal delta s (Loomis, 1990; Reid, 1995; Fig. 1.1). During the Pliocene, the SJB developed from a shall ow, marginal oceanic basin into a shallow lake after closure of the connecting seaway near the end of the Pliocene at 2.3 Ma (Loomis, 1990). Channels, such as the Priest Valle y Strait, connecting inland basins to the ocean act as chokes and reduce or eliminate tid al effects inside the basin by producing a phase lag in water elevation between the inland w ater body compared to the ocean tide (Kjerfve and Knoppers, 1991; LeBlond, 1991). Thus, the narrow and silled Priest Valley Strait would have limited tidal height and mixing w ithin and between the ocean and the

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6 SJB during the Pliocene. Variations in the rate of basin subsidence, sediment infill, and eustasy due to episodic movement of the San Andreas Fault also affected interchange of waters between the SJB and the open ocean (Stanton and Dodd, 1997). As a consequence of the limited tidal exchange, the hydrodynamic tur nover between the inland water body and the open ocean is substantially longer than for coastal estuaries (Kjerfve and Knoppers, 1991). Freshwater entering the SJB appea rs to have exceeded the tidal influx of marine water through the Priest Valley Strait du ring much of the Pliocene making the basin generally brackish except for limited periods during sea-level highstand when normal marine salinity prevailed (Bowersox, 2005; C hapter 6). Modern sea-surface temperatures of the Pacific Ocean at the same latit ude as the Coalinga region average 13.2 C (Loomis, 1990). Early Pliocene temperature s inferred from Etchegoin group macrofaunas increase during the early-mid Pliocene warm period then declining through the Late Pliocene in concert with the onset of nort hern hemisphere glaciation (Bowersox, 2005; Chapter 6).Chronostratigraphy Previous paleoecological studies addressed the issu es of timing in three manners: i.) related processes acting on the Etchegoin group fauna to the lithostratigraphic record and thus independent of any absolute timing of even ts; ii.) dealt with sufficiently small stratigraphic intervals such that all events record ed in the section were short-term and local, or iii.) interpreted the age of the Etchegoi n group such that the rates of processes and consequent reaction of the fauna would have bee n very slow. Examples of the first manner include Adegoke (1969), Stanton and Dodd (19 70), and Harris (1987). These studies developed actualistic paleoecological model s of the Etchegoin group fauna in the relative time sense of the lithostratigraphic and f ossil records and avoided issues of the temporal duration of events inside the SJB or corre lation outside of the basin. Thus, the record of environment and faunal succession within the SJB is simplified as local and independent of regional and global events. This is a valid approach where the correlation and absolute timing events is uncertain though the relationship of any external drive to internal SJB events remained unresolved or generali zed at best. The second manner of analyzing events occurring in small stratigraphic i ntervals is illustrated by Dodd and Stanton (1975). This study focused on the paleoeco logical events occurring in a single, short stratigraphic interval of limited areal exten t, the upper San Joaquin Formation Pecten zone of Woodring et al. (1940) in the Kettleman Hi lls, and thus the faunal record was representative of short-term, local environment al conditions and processes. This methodology allows the development of paleoecologic al models faunal distributions and environmental responses with applications outside o f the local basin. Loomis (1990) exemplifies the third manner. She interpreted the base of the Etchegoin group well into the late Miocene at ~8.4 Ma and the top in the lates t Pliocene at ~2.2 Ma. All environmental processes acting on the fauna as well as changes in faunal composition, structure, and distribution would have been compara tively slow. This approach is especially problematic because of the inherent isol ation of events in the SJB from regional and global events of eustasy and climate t hat this age model creates. These

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7 issues are addressed and resolved in Chapters 2-3. Supplemental data bearing on the Etchegoin group chronostratigraphy are presented in Appendix G. Methodology The ecologist, having an a priori knowledge of envi ronmental conditions that may affect the distribution of organisms under study, s eeks to explain the distribution of organisms from observed environmental parameters. Paleoecology, as in this study, applies a contrasting methodology where the composi tion and distribution of the remains of organisms are employed to infer those environmen tal conditions that may have determined observed distributions. For molluscan f aunas from the Pliocene SJB environmental preferences of extant species and gen era found in the faunas are used to infer paleoecologic relationships, factors determin ing spatial distributions, and paleoenvironmental conditions. That is, environmen tal parameters determined from extant taxa elements are invoked to infer the spati al distribution of all taxa. Thus, the presence or absence of a taxon may be construed as representative of the presence or absence of an associated environmental control (e.g ., Wargo Rub et al., 2002; Plissier et al, 2003). This study combines a database of presence-absence and semi-quantitative data gleaned from the literature with quantitative abund ance data from localities sampled in this study. Binary presence-absence faunal data fr om 425 localities (Arnold, 1909; Arnold and Anderson, 1910; Hoots, 1930; Woodring et al., 1940; Adegoke, 1969; Loomis, 1990) were compiled where the geographic lo cations and stratigraphic positions could be verified. The extensive collections by Wo odring et al. (1940) from 249 localities in the uppermost Etchegoin and San Joaqu in formations in the Kettleman Hills comprise ~60% of the previously published data compi led from the Etchegoin group. Adegoke (1969) and Loomis (1990) collected from a t otal of 168 localities primarily in the Jacalitos and Etchegoin formations from the Coa linga and Kreyenhagen Hills areas. Each reported four classes of qualitative relative abundance ranging from present to abundant for each identified taxon but without givi ng their bases for the distinction between classes. The relative abundance data of Ad egoke (1969) and Loomis (1990) were reduced to binary data for this study. In order to mitigate differences in the correlation of the base of the Etchegoin group in previous studies (e.g. Arnold, 1909; Arnol d and Anderson, 1910; Nomland, 1917; Adegoke, 1969; Loomis, 1990; Hall and Loomis, 1992), the relative stratigraphic positions of all fossil localities in this study we re established within a composite stratigraphic column constructed for the central Kr eyenhagen Hills where the complete Etchegoin group section is exposed. The relative s tratigraphic positions of Kettleman Hills collections of Woodring et al. (1940) were de termined from the location on the geologic map (their plate 3) and then correlated to the composite Etchegoin group stratigraphic section. The stratigraphic positions of the collections of Adegoke (1969) and Loomis (1990) were taken directly from these st udies and correlated to the composite Etchegoin group stratigraphic section. In toto these faunas (Arnold, 1909; Arnold and Anderson, 1910; Hoots, 1930; Woodring et al., 1940; Adegoke, 1969; Loomis, 1990; this

PAGE 23

8 study) form a stratigraphically constrained databas e that includes the entire Etchegoin group molluscan fauna (Table 1.1).Paleontological Methods and Data Preparation The analyses and conclusions presented in this stud y were developed from data gleaned from the Etchegoin group fossil record. In the course of this study, I attempted to visit andcollect in all areas where the occurrences of Etche goin group fossils had been noted in the literature or outcrops had been mapped. These occu rrences extend in a belt from the White Creek Syncline in the southernmost Diablo Ran ge on the north ~200 km southerly along the western margin of the SJB to Muddy Creek in the foothills of the north slope of the San Emidio Mountains in southern Kern County (F ig. 1.1). In the Coalinga region on the northwest margin of the SJB, western Fresno and Kings Counties, these areas included the White Creek Syncline (Arnold, 1909; Ar nold and Anderson, 1910; Dibblee, 1971), Priest Valley (Pack and English, 1914; Rose and Colburn, 1963; Dibblee, 1971), Coalinga Anticline (Arnold, 1909; Arnold and Anders on, 1910; Adegoke, 1969), Jacalitos Anticline (Arnold, 1909; Arnold and Ander son, 1910; Loomis, 1990), Kreyenhagen Hills (Arnold, 1909; Arnold and Anderso n, 1910; Adegoke, 1969; Loomis, 1990), Kettleman Hills North Dome, Kettleman Hills Middle Dome, and Kettleman Hills South Dome (Woodring et al., 1940). Due to my inab ility to gain access, I was unable to make collections from the Jacalitos Anticline and K ettleman Hills South Dome. South of the Coalinga region outcrops of the Etchegoin group are sparse. Etchegoin group fossils have been noted in the literature from the McKittri ck (Arnold, 1906), Fellows (Pack, 1920), Maricopa (Pack, 1920), Muddy Creek (Pack, 19 20; Hoots, 1930), and San Emigdio Creek (Hoots, 1930) areas in Kern County. Outcrops of the Etchegoin group have been mapped in the Bacon Hills and on Gould Hi ll in Kern County without descriptions of any fossil faunas (Dibblee, 1973). I made collections from the Bacon Hills, McKittrick, and Muddy Creek areas, but was u nable to locate the fossil-bearing outcrops described by Pack (1920) in the Fellows an d Maricopa areas, and time constraints prevented visiting the Gould Hill and S an Emigdio Creek areas. During 1999-2004 visits were made to 112 localities on the western margin of the southern SJB including two localities in the late M iocene Santa Margarita Formation on the Coalinga Anticline and six localities where sam ples of tuffs were collected for40Ar/39Ar age dating. My collections were constrained by available field time and access to outcrops thus dictating preferential sampling ( sensu Etter, 1999). At each locality, except those noted in Appendix A, the outcrop was m easured and described, photographed, and a non-standardized bulk sample av eraging 3.9 kg collected. The locality collections represent an application of cl uster sampling where the sample unit consists of a locality collection rather sampling f or individual taxa (Hayek and Buzas, 1997). Collections from 59 localities were process ed and the identifiable molluscs counted and tabulated. Weakly consolidated samples were wet sieved through 12 mm, 6 mm, and 3 mm screens. Large speci mens were recovered from the 12 mm

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9 Table 1.1. Areal and stratigraphic distributions and numbers of locality collections compiled in this study. Locations of Etchegoin gro up fossil localities (columns) are noted on Fig. 1.1: A. White Creek Syncline, B. Coalinga Anticline, C. Priest Valley, D. Jacalitos Anticline, E. Kreyenhagen Hills, F. Kettleman Hills, G. Bacon Hills, H. Muddy Creek.

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10 and 6 mm screens whereas the 3-6 mm fraction contained shell fragments of sm all bivalves, some fragments of large bivalves and gast ropods identifiable as outlined below, and in 15% of locality collections freshwater gastr opods were recovered. Indurated samples were photographed then broken apart and ide ntifiable specimens recovered. Specimens were morphologically identified to genus and species by comparison to illustrations in published monographs (Appendix B). A bivalve specimen was counted if the shell’s umbo was present whereas a gastropod wa s counted if the spire or aperture and body whirls were present. Because the collection f rom each locality was much smaller than the sampling domain, the volume of rock availa ble to be sampled, in collections without gastropods present each disarticulated biva lve valve was counted as an unique individual (Gilinsky and Bennington, 1994). In ord er to compensate for the greater likelihood of the two bivalve valves being sampled in a collection versus a single gastropod (Bambach and Kowalewski, 2000; Kowalewski et al., 2002, p. 243), where gastropods were present in a collection the number of bivalve valves was divided by two to arrive at the number of individuals present. A total of 5046 specimens were recovered representing 2597 individual bivalves from 65 speci es and 727 individual gastropods from 36 species. Of the total 101 species identifi ed, 44 species (31 species of bivalves and 13 species of gastropods) were ’singletons’ (i. e., present as a single occurrence in a single locality collection) representatives of rare species. Less abundant and rare species typically dominate the taxonomic makeup of natural systems (Cao and Williams, 1999) and rare live species are also rare dead species (K idwell, 2002). The difference in sample volumes between locality collections in this study required that individual abundance for each species in a bulk sample collection be normali zed to percent abundance (Appendix C) for subsequent statistical analysis (see the dis cussion in Zuschin et al., 2004, and the references cited therein) comparing the abundance d ata set to the same data set as presence-absence data. All locality collection dat a, both the set of 425 localities from the literature and the 59 localities of this study, wer e converted to presence-absence data for statistical analysis.Taxonomy and Ecology The composition of each locality collection was rev iewed and uniformly updated to the current accepted taxonomy to remove synonyms and uncertain identifications. The status of species, extinct versus living, was glean ed from Grant and Gale (1931), Merriam (1941), Reinhart (1943), Keen and Bentson (1944), M acNeil (1965), Addicott (1965), Morris (1966), Adegoke (1969), McLean (1969, 1978), Keen (1971), Hertlein and Grant (1972), Kern (1973), Kennedy (1974), Marincovich (1 977), Bernard (1983), Moore (1983, 1984, 1987, 1988, 1992, 1999, 2003), Turgeon et al. (1988), McLean and Gosliner (1996), Coan and Scott (1997), and Scott and Blake (1998). Approximately 35% of the Etchegoin group molluscan fauna consists of extant species. The total Etchegoin group mollusc fauna compiled herein consists of 176 speci es comprising 101 bivalve and 75 gastropod species. Neither polyplacophorans nor sc aphopods have been reported from the Etchegoin group nor were any found in the colle ctions made in this study. Identifying environmental variables and community c omposition and structure

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11 required compilation of the ecological and habitat preferences of the extant elements of the Etchegoin group fauna. Ecological preferences of taxa are taken from Keen (1963, 1971), Morris (1966), MacNeil (1967), Waller (1969) Golikov and Scarlato (1970), Morris et al. (1980), Rehder (1981), Smithy (1991), Coan et al. (2000), Minchin (2003), Tkachenko (2003), Lam and Morton (2004), and Sasaki et al. (2004). Many of the most common Etchegoin group bivalve genera and subgenera are now restricted to the western Pacific at latitudes comparable to central Californ ia or in the tropical eastern Pacific: Dendostrea (Lam and Morton, 2004), Mytilus ( Crenomytilus ) (Tkachenko, 2003), Pseudocardium (Golikov and Scarlato, 1970; Higano et al., 1997; Kamimura et al., 1999; Sasaki et al., 2004), Oppenheimopecten (Grau, 1959), Patinopecten (MacNeil, 1967; Minchin, 2003), and Swiftopecten (Minchin, 2003; Kulikova and Sergeenko, 2003). Cooccurrences of extant taxa in the Etchegoin group f auna are characteristic of modern California shoreline proximal environments at water depths <25 m. Taphonomy In the most general sense, taphonomic processes may create a fossil assemblage that is very different than the living community (D odd and Stanton, 1990). However, while preservation of fossil molluscs is influenced by a complex array of processes and circumstances, the faunal assemblages provide good to excellent records of community composition and environmental constraints, as well as spatial and temporal distribution of species (e.g., Kidwell and Flessa, 1996; Kidwell, 2 002). Transport from the original life habitat affects few individuals and most species wi th preservable hard parts are represented in the local assemblage and commonly in their correct rank order of abundance (Kidwell and Flessa, 1996; Kidwell, 2002) Dominici and Zuschin (2005) cautioned that considerable shell transport on gent ly sloping shelves may be more common than indicated in previous studies (e.g., Ki dwell and Flessa, 1996) due to infrequent major storms although the sedimentary pa rticles within tempestites can only rarely be related to their source areas (Dominici a nd Zuschin, 2005). Of the new 59 locality collections in this study, only one came f rom a demonstrable tempestite where shallow-water, hard-bottom taxa were found displace d shoreward in subtidal mud-bottom deposits reflecting comparable water depths of thei r life habitat. The remaining 58 collections were from low-depositional gradient for eshore, tidal-flat, and tidal-channel deposits where fossil material was plentiful. Spec imens showed little evidence of abrasion, fragmentation, or bioerosion suggesting m inimal transport, reworking, and exposure on the sea floor and rapid burial resultin g in largely parautochthonous assemblages ( sensu Kidwell et al., 1986). Minor taphonomic displacem ent of faunal elements was apparent in locality outcrops and in b ulk samples during processing in the form of bathymetrically displaced taxa (generally i ntertidal genera such as Solen among open-water taxa or deeper water taxa such as Turritella found with tidal-flat species) or faunal elements displaced from adjacent habitats (h ard-bottom taxa such as Mytilus found with sand-flat taxa such as Macoma ). Preservation was excellent for calcitic taxa (oyste rs, pectinids, mussels, and the gastropod Littorina ) but generally poor for aragonitic taxa with most shells showing

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12 effects of leaching to the extent that specimens te nded to fragment during collection in the field and processing in the laboratory. Collec tions from several localities consisted entirely of molds of aragonitic taxa. It could be argued that the composition of locality collections may be biased due to differential prese rvation of thick-shelled taxa versus thin-shelled taxa. However, Behrensmeyer et al. (2 005) found that taphonomic effects are neutral with respect to durability. In this st udy there was no evidence of complete taphonomic loss of aragonitic taxa from locality co llections leaving only calcitic taxa nor cases where collections with similar calcitic taxa compositions lacked the expected, associated aragonitic taxa especially thin-shelled forms (e.g. Mya Macoma Modiolus Psephidia and Solen ). Analysis of Faunal Composition The basis for the statistical analysis in this stud y are two datasets determined from locality collections: the number of species present in a locality collection (species richness, S), and the number of locality collection s in a sample interval where a given species was found (occurrences, N). The presence-a bsence data set of 484 locality collections was divided for multivariate analysis i nto 15 stratigraphic sample intervals corresponding to the SJB 4th-order eustatic cycles each consisting of from 12 t o 81 locality collections (Fig. 1.2; Appendix E). The s mallest and largest number of locality collections comprising a sample interval were from the upper Jacalitos and the Siphonalia zone of Woodring et al. (1940) in the uppermost Etc hegoin, respectively. Temporal resolution as a uniform vertical stratigraphic dist ribution of locality collections within a sample interval is best in the basal Jacalitos, upp ermost Etchegoin, and upper San Joaquin formations (Fig. 1.3). Spatial resolution of biofa cies within these sample intervals was most refined where many locality collections were g eographically widely distributed and fell within a small stratigraphic interval. Popula tion indices, S and N were compiled from locality collections (n) in 116 ten-meter stra tigraphic sample intervals (Fig. 1.4). Sample intervals included a range of 1-27 locality collections (average of 4), and thus may include an associated range of potentially samp led biofacies. S and N are crosscorrelated (r2 = 0.86) allowing the use of occurrences as a proxy for abundance because an ecological group with more occurrences is likely to have been locally more abundant, had a greater geographic distribution, as well as a broader environmental range (Hayek and Buzas, 1997; Buzas and Culver, 1999; Madin et a l., 2006). Sampling was greatest (Fig. 1.4) in the uppermost E tchegoin (~1500-1700 m) and basal upper San Joaquin (~2100-2300 m) where the Etc hegoin group is best exposed. In order to test for bias due to greater sampling inte nsity of better exposed sections the Etchegoin group fauna was modeled after the techniq ue of Crampton et al. (2003). Outcrop areas were determined for nine stratigraphi c intervals within the marine section of the Etchegoin group exposed in the Coalinga regi on corresponding to the fauna zonules of Adegoke (1969), the smallest practical s cale for this test, from the geologic maps of Woodring et al. (1940), Adegoke (1969), Dib blee (1971), Hall and Loomis (1992), and field work of this study. The outcrop area of the Etchegoin group marine section in the Coalinga region totals ~340 km2 and ranges from a low of ~3 km2 of

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13 exposed and preserved basal Jacalitos (zonule 8 of Adegoke, 1969) on the Coalinga Anticline to a high totaling ~80 km2 of uppermost Etchegoin (zonule 12 of Adegoke, 1969; Patinopecten through Littorina zones and their correlates of Woodring et al., 194 0) exposed in the Kettleman Hills North, Middle, and S outh Domes. Spearman's correlation coefficient matrix was calculated using the module in PAST software version 1.45 (PAlaeontological STatistics; Hammer et al., 2001) for the outcrop area (A) of each of the nine stratigraphic intervals and the number of loca lity collections (n), S, and N from each interval (Table 1.2A). In contrast to the results of Crampton et al. (2003), correlation is not significant between A and any of the three test ed factors (p > 0.05) suggesting that the nature of the collections of the Etchegoin grou p in toto have not introduced a bias when the data for species richness and other paleoe cologic components are compiled. A second Spearman's correlation coefficient matrix was calculated for n, S, and N from the 116 ten-meter stratigraphic sample (Table 1.2B). Not unexpectedly, correlation exists between n, S, and N (p < 0.05). However cor relation does not demonstrate causation. N is largely explained by n (r2 = 0.82; more collections yields more occurrences of taxa). S is weakly related to n (r2 = 0.58) suggesting that abundant taxa are not overly represented in the locality collecti ons. This relationship is much like that examined by Poore and Rainer (1974) in which they c oncluded that differences in regional diversity are not related to sample size. The corollary to over-represented abundant taxa is the under representation of middle-rank and rare taxa. The rank abundance of species in a n atural population is a log-normal relationship (Buzas et al., 1982; Hayek and Buzas, 1997; Buzas and Culver, 1999). To test for under-representation species in the Etcheg oin group fauna, the rank occurrences of the species from the 15 stratigraphic intervals deposited during the 4th-order eustatic cycles (Fig. 1.2) was determined (Fig. 1.5A-D). Th e rank occurrences of species in the lower Jacalitos fauna (Fig. 1.5A) is indicative of under-represented middle-rank and rare species which suggests any conclusions that may be drawn from that portion of the fauna should be considered tentative. Five other faunas (upper Jacalitos, upper Etchegoin A, Littorina zone, Trachycardium zone, and Acila zone; Fig. 1.5A-B, D) are demonstrative of the under-representation of rare species althoug h the presence or absence of only rare taxa does not have a significant effect on analysis of diversity (Marchant, 1999). Statistical Analysis Chapters 4 and 5 present statistical models explain ing the spatial and temporal distributions and structure of the Etchegoin group molluscan fauna. Multivariate analysis (Chapter 4) was performed using the modules in PAST software version 1.45 (PAlaeontological STatistics; Hammer et al., 2001). Questions of community composition and environmental gradients explaining the spatial distribution and temporal variations of communities determined the methods an d metrics appropriate to this study as outlined in the recommendations of Shi (1993). Locality data were analyzed by sample interval in three steps with multivariate explorato ry metrics: Detrended Correspondence Analysis ordination (DCA; discussed in Peet et al., 1988) to delineate the environmental gradients that determined distribution of the organ isms, Q-mode cluster analysis

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14 Figure 1.3. Outcrop area of marine Etchegoin group stratigraph ic intervals corresponding to the fauna zonule of Adegoke (1969) and the number of localities per interval. The test for bias due to greater samplin g intensity of better exposed sections the Etchegoin group fauna was modeled after Crampton et al. (2003) where outcrop area of stratigraphic intervals (A) are tested against the number of locality samples from each of the intervals (n). The total outcrop area of the Etchegoin group i n the Coalinga region is ~340 km2 and ranges from ~3 km2 of exposed and preserved basal Jacalitos (zonule 8 of Adegoke, 1969) on the Coalinga Anticline to a high totaling ~80 km2 of uppermost Etchegoin (zonule 12 of Adegoke, 1969; Patinopecten through Littorina zones and their correlates of Woodring et al., 1940) exposed in the Kettleman Hills North, Middle, and South Domes (Fig. 1.1). Spearman's correlation coe fficient matrix was calculated from the data from each stratigraphic interval using the module in PAST software version 1.45 comparing A, n, S, and N from each interval (Table 1.2A). Contra ry to the results of Crampton et al. (2003) correlation cannot be proved between A and any of the three tested factors (p > 0.05) suggesting that the Etch egoin group in toto has been appropriately collected.

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15 Figure 1.4. Species richness and occurrences in locality coll ections. Species richness and occurrences from 484 locality collections were compiled in 116 ten-meter sample intervals. The number of locality collections compr ising 10 m sample intervals shoes sampling to have been heaviest in the uppermost Etc hegoin (~1500-1700 m) and basal upper San Joaquin (~2100-2300 m) where the Etchegoin group is best exposed (Table 1.2). This figure demonstrates the relationship be tween species richness and abundance (Table 1.2A): species are most abundant where there are many species present. While the number occurrences correlates well to the number of localities in a sample interval ( r2 = 0.82) species richness only weakly relates to sampl ing intensity (r2 = 0.58) suggesting that it is unlikely that abundant taxa are over represen ted in the locality collections. SJB extinction events are noted A-H (adapted from Bower sox, 2005; Chapter 6).

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16 Figure 1.5. Test for under-represented species in the Etchego in group fauna. Underrepresentation of species in the Etchegoin group fa una was tested by ranking the occurrences the species from the 15 stratigraphic i ntervals deposited during the 4th-order eustatic cycles (Fig. 1.2). The rank abundance of species in the lower Jacalitos fauna (A) is indicative of under-represented middle-rank and rare species which mitigates any conclusions that may be drawn from statistical anal ysis of the fauna. Five faunas (upper Jacalitos, upper Etchegoin A, Littorina zone, Trachycardium zone, and Acila zone; A-B, D) are demonstrative of the under-representation of rare species although the presence or absence of rare taxa does not have a significant ef fect on diversity analysis (Marchant, 1999). Faunas from the balance of the intervals ha ve been adequately sampled.

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17 Table 1.2A. Test of correlation between outcrop area and the number of localities, species richness, and number of occurrences. Corre lation was tested between the outcrop area (A) of each of the nine stratigraphic interval s and the number of locality collections (n), S, and N from each interval. Correlation coef ficients are given below the diagonal whereas the probabilities that the quantities being compared are not correlated are given above the diagonal. Contrary to the results of Cra mpton et al. (2003) correlation cannot be proved between A and any of the three tested fac tors (p >0.05) suggesting that the Etchegoin group in toto has been appropriately collected. Table 1.2B. Test of correlation between the number of localit ies, species richness, and number of occurrences. Correlation was tested for n, S, and N from the116 ten-meter stratigraphic sample. Not unexpectedly, correlatio n is proved between n, S, and N (p <0.05). N is largely explained by n (r2 = 0.82; more collections yields more occurrences of taxa) therefore suggesting that all taxa are app roximately uniformly sampled at all sampling intensities. S is weakly related to n (r2 = 0.58) suggesting that abundant taxa are not overly represented in the locality collections.

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18 (discussed in Dodd and Stanton, 1975, p. 52-53) of DCA coordinates using UPGMA of the Euclidean distance coefficient to identify comm unity associations, and ordination (Shi, 1993, p. 226) by Non-Metric Dimensional Scali ng (NMDS) to cross-check the congruency and rigor of the clustering in identifyi ng cluster-group community associations. These three metrics reduce the withi n-sample variability to environmentally interpretable coordinates in two-dimensional space. Where to partition cluster analysis can be problematic (Romesburg, 1984) and has been a ccomplished in two manners: either by a fuzzy partitioning into community associations by inspection (e.g. Pillar, 1999), or partitioning where there is the greatest range in t he similarity between dendrogram branches (Romesburg, 1984). In this study, I compa red fuzzy partitioning and partitioning where the similarity range is greatest and found that partitioning by the greatest similarity range could not be reliably res olved by NMDS whereas NMDS did resolve fuzzy partitions. Summarized results are t abulated in Appendix D-E. Species richness and the number of locality collections in a sample interval where a given species was found (occurrences) were compiled in ten-meter sample intervals. Population indices including the Shannon informatio n function (diversity index, H; Shannon, 1948) and evenness (E; Buzas and Gibson 1969; Hayek and Buzas, 1997) were calculated from S and N (Buzas and Culver, 199 9) for the total fauna (HT), nonendemic fauna (HM), and endemic fauna (HE) from each 10 m sample interval using the Diversity Indices module of PAST (Chapter 5). The relative value of H is a measure of diversity in a population in terms of the number of species and the distribution of individuals among those species (Hayek and Buzas, 1 997), whereas E is an index of how individuals are distributed among species in a popu lation (Hayek and Buzas, 1997) where a value of one indicates that all species are repre sented by an equal number of individuals. Summarized results are tabulated in Appendix F. Ove rall structure of the Etchegoin group fauna was tested by comparing HT and E to S for each sample interval (Chapter 5). To test the effects of scaling on diversity, H was cal culated for the total fauna from each 4thorder eustatic cycle during Etchegoin group deposit ion, for each of the three formations comprising the Etchegoin group, and for the Etchego in group in toto (Chapter 5). Contents of Appendices Six appendices of supplementary data are included i n this dissertation. Included is a catalog of the 108 fossil localities visited wher e collections were made during this study, a table of the stratigraphic position and fa unal data from each of the 484 localities used in these studies, statistical plots of multiva riate analysis summarized by stratigraphic interval, a table summarizing the locality data and analysis in ten-meter sample intervals, a table summarizing statistical analysis of faunal diversity in ten-meter sample intervals, and reports of 40Ar/39Ar age dating analysis performed by the University of Nevada at Las Vegas, Geochronology Laboratory.Appendix A Appendix A is a catalog of the localities visited a nd 112 collections made during 1999-2004. Column one lists the locality numbers s erially as an eight digit number by the

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19 date on which they were collected: a six-digit numb er indicating the day, month, and year the locality collection was made, and a two digit n umber following a decimal point indicating the serial number of the locality for th e particular date with a lettered subcollection noted, if any. For example, locality 10 0700.04a was a sub-collection of the fourth locality collection made on October 7, 2000. Column two indicates on which of the 12 index maps the locality is plotted. Column three indicates the United States Geological Survey 7 minute topographic quadrangle where the locality is situated. Column four gives the map coordinates in feet relat ive to the section lines where the locality is situated and columns five and six are t he section number, Township, and Range. All localities lie inside the Mt. Diablo Ba se and Meridian except locality 053102.01 in Muddy Creek which lies inside the San Bernardino Base and Meridian. Column seven explains processing of the locality co llection. Column eight gives reference to any notes and column nine gives any pe rtinent remarks about the particular locality, the relationship to previous studies in t he area, or disposition of the sample. Appendix B Appendix B comprises my Catalog of the Late Neogene Molluscs from the Coalinga Region, Fresno and Kings Counties, Califor nia (Santa Margarita Formation and Etchegoin group): Part 1: Plate References. Part 2, copies of the plate figures referenced in Part 1, is not included for space and copyright concerns. This catalog was compiled to reduce the number of references require d for the identification of specimens during processing to a single source.Appendix C This appendix tabulates the percent abundances of s pecies recovered and identified from the 59 locality collections made du ring this study (Appendix A). Appendix D Appendix D consists of the plots of DCA axes 1-2 an d cluster plots of the DCA values. This data was used to determine the mollus c communities discussed in Chapter 4. Analyses were performed in intervals corresponding to the 3rdand 4th-order eustatic cycles (representing approximately 40 kyr) comprising the stratigraphic members of the Jacalitos through lower interval of the upper Etche goin and zones of Woodring et al. (1940) for the uppermost Etchegoin through uppermos t San Joaquin (Fig. 1.2). Appendix E Appendix E tabulates the results of multivariate an d diversity analysis for the 484 localities of this study. The stratigraphic level, community membership determined from cluster analysis for the fauna from the locality co llection, water paleodepth determined from DCA analysis, effective temperature represente d by the fauna [effective temperature is discussed in Loomis(1990) and Hall (2002)], spec ies richness of the total fauna and endemic faunas, diversity and evenness of the total fauna, and DCA axes 1-2 scores. Notes at the end of the table explain the column he adings. The results of this analysis is

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20 presented and discussed in Chapter 4.Appendix F Diversity analysis for each 10 m sample interval is presented in Appendix F. For each stratigraphic interval, the species richness, occurrences, and number of locality collections comprising the sample are given for the total and endemic faunas; diversity index for the total and endemic faunas and total fa una at the scale of 3rd-and 4thorder eustatic cycles (Fig. 1.2), individual formations c omprising the Etchegoin group, and the Etchegoin group in toto ; and total fauna evenness. Notes at the end of th e table explain the column headings. The results of this analysis is presented and discussed in Chapter 5. Appendix G Appendix G consists of the reports of 40Ar/39Ar age dating of two tuff samples from the Kettleman Hills by the University of Nevad a at Las Vegas Geochronology Laboratory.ReferencesAddicott, W.O., 1965, Some western American Cenozoi c gastropods of the genus Nassarius : United States Geological Survey, Professional Pa per 503-B, 23 p., 3 pl. Adegoke, O.S., 1969, Stratigraphy and paleontology of the marine Neogene formations of the Coalinga region, California: University of Cali fornia, Publications in Geological Sciences, v. 80, 241 p., 13 pl. Anderson, F.M., 1905, A stratigraphic study in the Mount Diablo region of California: Proceedings of the California Academy of Sciences, 3rd Series, v. 2, p. 155-248. Argus, D.F., and Gordon, R.G., 2001, Present tecton ic motion across the Coast Ranges and San Andreas fault system in central California: Geological Society of America Bulletin, v. 113, p. 1580-1592. Arnold, R., 1906, The Tertiary and Quaternary pecte ns of California: United States Geological Survey Professional Paper 47, 264 p. Arnold, R., 1909, Paleontology of the Coalinga dist rict, Fresno and Kings Counties, California: United States Geological Survey, Bulle tin 396, 173 p., 30 pl. Arnold, R., and Anderson, R., 1910, Geology and oil resources of the Coalinga district, Fresno and Kings Counties, California: United Stat es Geological Survey, Bulletin 398, 354 p. Bambach, R.K., and Kowalewski, M., 2000, How to cou nt fossils [abstract]: Geological Society of America, Abstracts with Programs, v.32, no.7, p.95. Barbat, W.F., and Galloway, J., 1934, San Joaquin C lay, California: American Association of Petroleum Geologists Bulletin, v. 18 p. 476-499. Bartow, J.A., and Pittman, G.M., 1984, The Kern Riv er Formation, southeastern San Joaquin Valley, California: United States Geologica l Survey Bulletin 1529D, 17 p.

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27 Turgeon, D.D., Bogan, A.E., Coan, E.V., Emerson, W. K., Lyons, W.G., Pratt, W.L., Roper, C.F.E., Scheltema, A., Thompson, F.G. and Wi lliams, J.D., 1988. Common and Scientific Names of Aquatic Invertebrate s from the United States and Canada – Mollusks. American Fisheries Society, Bethesda, Maryland, 277 pp. Wakabayashi, J., and Sawyer, T.L., 2001, Stream inc ision, tectonics, uplift, and evolution of topography of the Sierra Nevada, California: Jo urnal of Geology, v.109, p.539-562. Waller, T.R., 1969, The evolution of the Argopecten gibbus stock (Mollusca: Bivalvia), with emphasis on the Tertiary and Quaternary specie s of eastern North America: Memoir of the Paleontological Society, v. 3, Supple ment to the Journal of Paleontology, v. 43, no. 5, 125 p. Wargo Rub, A.M., Wright, D.J., and Jones, J.A., 200 2, A novel landscape ecology approach for determining habitat correlations and m acrofaunal patchiness in extreme environments: pilot study for the Southern East Pacific Rise at 17-18 degrees S: Cahiers de Biologie Marine, v. 43,p. 307 -311. Watts, W.L., 1894, The gas and petroleum yielding f ormations of the Central Valley of California: California State Mining Bureau Bulletin v. 3, 100 p., 7 pl. Wilson, I.F., 1943, Geology of the San Benito Quadr angle, California: California Journal of Mines and Geology, v. 39, p. 183-270. Woodring, W.P., Stewart, R., and Richards, R.W., 19 40, Geology of the Kettleman Hills oil field, California: United States Geological Sur vey Professional Paper 195, 170 p., 56 pl. Zuschin, M., Harzhauer, M., and Mandic, O., 2004, S patial variability within a single parautochthonous Paratethyan tidal flat deposit (Ka rpatian, lower Miocene – Kleinebersdorf, Lower Austria): Courier ForschungsInstitut Senckenberg, v. 246, p. 153-168.

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28 Chapter 2 Chronostratigraphic Framework of the Pliocene Etchegoin Group, San Joaquin Basin, Central Califor nia AbstractThe lithostratigraphic relationships of the Jacalit os, Etchegoin, and San Joaquin formations comprising the Etchegoin group of the Sa n Joaquin Basin (SJB) have been established for nearly 100 years, but their chronos tratigraphic position has been problematic for nearly as long. As demonstrated he re, the age of the Etchegoin group is constrained at ~5.3-2.2 Ma through a combination of biostratigraphy and tephrochronology and fission track age dates where corroborated by biostratigraphy. The boundary between the underlying Reef Ridge Formatio n and the Etchegoin group is placed at the Miocene-Pliocene boundary at ~5.3 Ma b ased on diatom stratigraphy from the southern SJB although benthic foraminiferal bi ostratigraphy from the central SJB suggests that the uppermost Reef Ridge Formation in the central SJB may be correlative with the basin-margin Jacalitos Formation. Diatom stratigraphy places the JacalitosEtchegoin formations boundary at 4.8 Ma. Average d epositional rates within the Jacalitos suggests an age for the lower-upper Jacal itos boundary at ~5.1 Ma. Biostratigraphy of vertebrate faunas suggests the a ge of the Etchegoin-lower San Joaquin formations boundary at ~4 Ma with deposition of the lower San Joaquin formation constrained to the interval ~4-3 Ma. Depositional r ates within the Etchegoin Formation and correlation of the SJB 3rd order eustatic cycles to the Gulf of Mexico record constrains the lower-upper Etchegoin Formation boun dary at 4.4 Ma and corroborates the age of the top of the upper Etchegoin Formation at 4 Ma. Vertebrate biostratigraphy, tephrochronology, and depositional rates suggests t hat the lower-upper San Joaquin Formation boundary is at ~3.1 Ma. The boundary betw een the upper San Joaquin Formation and overlying Tulare Formation is inferre d from diatom biostratigraphy at ~2.23 Ma. Radiometric and stable isotope numerical age dates are not generally supported by Etchegoin group lithostratigraphic rel ationships and biostratigraphy. 87Sr/86Sr age dates from the Etchegoin group suffer from t he ambiguity of ages derived from the Neogene 87Sr/86Sr seawater curve as well as complications due to b rackish conditions in the SJB. New 40Ar/39Ar age dates from tuffs in the uppermost Etchegoin and lower San Joaquin Formations in the Kettleman H ills show effects of excess Ar; thus, all Etchegoin group radiometric age dates are poten tially equivocal. The many spurious Etchegoin group correlations by tephrochronology de monstrate that this age-dating technique should be applied with caution and only u sed in conjunction with independent,

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29 corroborating evidence in support of those correlat ions. Introduction and Previous Work The San Joaquin Basin (SJB) is a structural trough comprising the southern Great Valley of central California (Fig. 2.1) where a thi ck section of pre-Quaternary strata is exposed in the foothills of the mountain ranges fla nking the eastern, southern, and western basin margins. Post-Pliocene uplift and de formation has best exposed the thick section of late Neogene strata of the latest Miocen e Reef Ridge Shale and Santa Margarita Formation through Plio-Pleistocene Tulare Formation in the foothills of the Temblor and Diablo Ranges in an ~75 km belt extending from north of Coalinga, California, southwest through the Kreyenhagen and Kettleman Hills (Fig. 2 .2). The Etchegoin group (informal SJB nomenclature), is perhaps the thickest and best exposed section of Pliocene strata in California, and includes the Jacalitos, Etchegoin, and San Joaquin formations (Reed and Hollister, 1936; Wilson, 1943; Loomis, 1990). It o verlies the latest Miocene basinal facies Reef Ridge and basin-margin facies Santa Mar garita Formations and earlier strata and is overlain by the latest Pliocene-Pleistocene Tulare Formation and member boundaries within the Etchegoin group correspond to eustatic lowstands (Chapters 4-6) as identified by Miller et al. (2005). Historically, the Etchegoin group has been considered the definitive Pliocene section for central Califor nia (Nomland., 1917; Goudkoff, 1934; Woodring et al. 1940; Adegoke, 1969; Stanton and Do dd, 1976). There have been many methods applied to the problem of late Neogene SJB chronostratigraphy: biostratigraphy (e.g. Arnold, 1 909; Merriam, 1915; Goudkoff, 1934; Addicott, 1972; this study), stable isotope stratig raphy (Loomis, 1990, 1992b; Mahan et al., 2001), tephrochronology (Sarna-Wojcicki, 1976; Sarna-Wojcicki et al., 1979, 1991; Perkins, 1987), and radiometric and zircon fission track numerical age dating (Obradovich, 1975, in Reppening and Tedford, 1977; Obradovich et al., 1978; Loomis 1990, 1992a; this study) Individually each of th ese methods has its strengths but when compared provide conflicting results. This study c larifies the stratigraphic relationships of the Etchegoin group, demonstrates its relative a ge assignment to the Pliocene, and develops a chronostratigraphic model for the Etcheg oin group with numerical ages for the major divisions of the section. This is a step nec essary to fully understand the timing of events and rates of processes forcing environmental change affecting the molluscan fauna of the late Neogene SJB. In this stratigraphic seq uence it is critical to have a wellconstrained chronostratigraphic framework to establ ish temporally synchronous faunas within a regionally heterogeneous paleoenvironmenta l landscape. Only then is it possible to develop a model that explains the rates and timi ng of evolutionary/ecologic events. Stratigraphic nomenclature as used herein is intend ed to be in accordance with the North American Stratigraphic Code (NASCN, 2004).Etchegoin Group Stratigraphy On the northwest margin of the SJB, the Etchegoin g roup consists of a thick succession of non-marine to shallow-marine facies t otaling 2430 m in a composite section

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30 Figure 2.1. Early Pliocene paleogeography of central Californ ia at ~5 Ma (modified with annotations from Bowersox, 2004; Chapter 3). Locat ion of the SJB with the approximate extent of the Pliocene marginal ocean basin shaded is noted on the inset map of California. Faults west of the San Andreas are not shown. Location of La Honda and Santa Maria Basins are shown relative to the SJB at that time. The modern shoreline and cities locations are shown for reference. Location s of Etchegoin Group outcrop areas are noted: A. White Creek Syncline, B. Coalinga Anticline, C. Priest Valley, D. Jacalitos Anticline, E. Kreyenhagen Hills, F. Kettleman Hills, G. Lost Hills oil field, H Bacon Hills, I. Muddy Creek.

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31 Figure 2.2. Locations of type sections of the Etchegoin Group members, the underlying Reef Ridge and Santa Margarita Formations, and the overlying Tulare Formation in sequence by their publication years: A – Etchegoin Formation (F.M. Anderson, 1905); B – Santa Margarita Formation (Arnold and R. Anderson 1910; Nomland, 1917); C – Jacalitos Formation (Arnold and R. Anderson, 1910); D – Reef Ridge Formation (Barbat and Johnson, 1934; Siegfus, 1939); E – San Joaquin Formation (F.M. Anderson, 1905; Barbat and Galloway, 1934); and F – Tulare Formation (F.M. Anderson, 1905; Woodring et al., 1940). (~200 m thick, Woodring et al., 1940 ), lower San Joaquin Formation (400 m thick as adapted from Woodring et al., 1940) and upper San Joaquin Formation (335 m thick as adapted from Woodring et al., 1940). The outcrop area of the marine section of the Etchegoin group in the Coalinga region totals ~3 40 km2 and ranges from a low of ~3 km2 of exposed and preserved basal Jacalitos on the Co alinga Anticline to a high totaling ~80 km2 of uppermost Etchegoin Patinopecten through Littorina zones and their correlative strata, as discussed by Woodring et al. (1940), exposed in the Kettleman Hills North, Middle, and South domes.

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32 that has been measured and described in many studie s (Arnold and Anderson, 1910; Woodring et al., 1940; Adegoke, 1969; Stanton and D odd, 1972; Loomis, 1990; Hall and Loomis, 1992; Fig. 2-4): the Jacalitos Formation (6 35 m thick as adapted from Hall and Loomis, 1992), Etchegoin Formation (1060 m thick as adapted from Hall and Loomis, 1992) which includes the uppermost Etchegoin Format ion exposed in the Kettleman Hills (~200 m thick, Woodring et al., 1940), lower San Joa quin Formation (400 m thick as adapted from Woodring et al., 1940) and upper San J oaquin Formation (335 m thick as adapted from Woodring et al., 1940). The late Neogene stratigraphy of the SJB has been w ell known and described from exposures on the basin’s northwest margin for a century. Major studies of the stratigraphy and paleontology of the late Neogene s trata in the Coalinga region were completed in three periods: 1905-1917, 1933-1946, a nd 1969 to the present and many conflicting interpretations of the SJB’s lithostrat igraphy, biostratigraphy, and chronostratigraphy have been advanced (Fig. 2.2-2.3 ). Figure 2.3 summarizes the history of lithostratigraphic nomenclature of the late Neog ene section of the SJB. Anderson (1905) defined and named the Etchegoin beds for the type locality on Etchegoin Ranch ~20 km northeast of Coalinga, California (Fig. 2.2), as well as described and named the overlying, non-marine Tulare Formation. The Etcheg oin beds were defined as that strata overlying the post-Eocene Coalinga beds (Anderson, 1905). Anderson (1905) further subdivided the Etchegoin beds into two loosely defi ned members described as the lower Etchegoin sands and upper San Joaquin clays. Both the Etchegoin group and the Tulare Formation were assigned to the Pliocene by Anderson (1905, 1908) based on their stratigraphic positions overlying characteristicall y Miocene rocks and their included molluscan faunas. Arnold (1909) and Arnold and And erson (1910) described the geology and paleontology of the Coalinga district, an area of ~2000 km2 extending from the north flank of the Coalinga Anticline to the Kern County line (Fig. 2.2), refining the stratigraphic interpretations of Anderson (1905, 19 08) by dropping the San Joaquin clays as a division of the upper Etchegoin and describin g the Jacalitos Formation as the ~3600 ft (~1100 m) of strata exposed in the Kreyenhagen Hi lls along Jacalitos Creek, southwest of Coalinga, overlying their newly defined Santa Ma rgarita Formation. The Jacalitos was assigned an early upper Miocene age based on its ab undant and well-preserved molluscs (Arnold, 1909). Merriam (1915), in his review of t he terrestrial vertebrate faunas of the Etchegoin group, concluded that the Jacalitos was e arly Pliocene and that the Etchegoin was no older than middle Pliocene. Nomland (1916a) formally defined the base of the Jacalitos north of Coalinga and presented a correla tion chart of the marine and terrestrial facies of the Santa Margarita through Tulare format ions. Nomland (1916b) described the invertebrate fauna from the Jacalitos from its type section correlated the Jacalitos section to the lower Pliocene. However Nomland (1917) conc luded that the stratigraphy, paleontology, and geologic history of the Jacalitos were closely related to that of the Etchegoin and included the Jacalitos in the lower E tchegoin Formation and defined the Etchegoin group as comprising the lower and upper E tchegoin formations (Fig. 2.3). In contrast to the correlations of Arnold (1909) and A rnold and Anderson (1910), Nomland

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33

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34 (1917) assigned the entire Etchegoin group to the P liocene. Barbat and Galloway (1934) restored the San Joaquin to the Etchegoin group by formally defining the San Joaquin Clay and designating its type section in the Kettle man Hills North Dome (Fig. 2.2-2.3). Reed and Hollister (1936) defined the Etchegoin gro up of Nomland (1917) as including the Jacalitos, Etchegoin, and San Joaquin formation s, the framework of the lithostratigraphy of this study. The most detailed study of Etchegoin-Tulare geology and paleontology was completed by Woodring et al. (1940) in the Kettlema n Hills. The uppermost 200 m of Etchegoin strata exposed in the Kettleman Hills was divided into five characteristic faunal zones, the basal San Joaquin Cascajo Conglom erate member was established and type section designated, five characteristic faunal zones defined in the San Joaquin, and a formal type section designated for the Tulare (Wood ring et al., 1940; Fig. 2.2-2.4). The boundary between the Etchegoin and San Joaquin form ations was established at the base of the Cascajo Conglomerate and the base of the upp er San Joaquin was equated with the base of the Pecten zone of Woodring et al. (1940), establishing an in formal stratigraphic division of the San Joaquin into lower and upper me mbers. A type section for the Tulare Formation was designated by Woodring et al. (1940) at La Ceja, on the northeast plunge of Kettleman Hills North Dome (Fig. 2.2), to formal ize the Tulare as originally described by Anderson (1905). Adegoke (1969) presented a com prehensive study of the stratigraphy and invertebrate macrofossil paleontol ogy, paleoecology, and biostratigraphy of the early Miocene through late Pliocene section of the Coalinga Anticline and Kreyenhagen Hills based on extensive sampling and s tratigraphic measurement of the section. The section was divided into eight major faunal units without chronostratigraphic implication, each characterized by a widely distributed fossil assemblage and further subdivided into 16 zonules c haracterized by the association of several species (Adegoke, 1969). However, although these descriptive units were carefully erected and focused only on those taxa an d lineages of probable time significance, ignoring those taxa whose distributio n is facies controlled (Adegoke, 1969), the application of this approach remains untested o utside of the areas studied. Provincial Molluscan Stages Addicott (1972) developed a qualitative biostratigr aphic framework for California’s post-Eocene molluscan fossil record ba sed on stratigraphic and faunal data from the Temblor Range of the central California. Six post-Eocene central California provincial molluscan stages were established for an d stratotypes designated (Addicott, 1972) for the pre-Pliocene section. The “Jacalitos ,” “Etchegoin,” and “San Joaquin” provincial molluscan stages (“Jacalitos” stage, “Et chegoin” stage, “San Joaquin” stage) of Addicott (1972), denoted as informal nomenclature b y setting the names in quotation marks, were established from the Etchegoin group st rata and faunas although his nomenclature violates North American Commission on Stratigraphic Nomenclature (NASCN) (2004) Article 77 by applying lithostratigr aphic to a chronostratigraphic unit. The descriptions of the “Jacalitos,” “Etchegoin,” a nd “San Joaquin” stages of Addicott

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35 Figure 2.4. Composite stratigraphic section of the Etchegoin Group and Pliocene northwest SJB 4th order relative sea level curve (modified from Bowe rsox, 2004; Chapter 3). The division of the San Joaquin Formation into informal lower and upper members at the base of the upper San Joaquin Formation Pecten zone was first used by Woodring et al. (1940) and has been followed in this paper. Su bdivisions of the upper Etchegoinupper San Joaquin section from 1200-2500 m stratigr aphic levels are generalized from Woodring et al. (1940). Stratigraphic positions of tuff beds withing the upper Etchegoin, San Joaquin, and basal Tulare Formations from Sarna -Wojcicki et al. (1979, fig. 3) and

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36 (Figure 2.4, Continued) Sarna-Wojcicki et al. (1991, pl. 1), Perkins (1987 p. 12-15), Loomis (1990a, 1992a), and this study. Not shown a re tuffs in the lower Etchegoin and Jacalitos on the Coalinga Anticline (Perkins, 1987 p. 12-15) and in the Kreyenhagen Hills (Loomis, 1990a, 1992a). A – Localities 030202.07-09 (this study, Appendix A) ; B – Locality 030202.05 (this study, Appendix A); C – Den Hartog tuff of Loomis (1990a, 1992a); D – Lawlor Tuff of Sarna-Wojcicki et al. (1979, fig. 3) and Sarna-Wojcicki et al. (1991, pl. 1); Locality 052802.08 (this study, Appe ndix A); E – Nomlaki Tuff of SarnaWojcicki et al. (1979, fig. 3) and Sarna-Wojcicki e t al. (1991, pl. 1); Locality 030202.01a-01c (this study, Appendix A); F – Tuff SW-B of Perkins (1987); G – Ishi Tuff of Sarna-Wojcicki et al. (1979, fig. 3) and Sa rna-Wojcicki et al. (1991, pl. 1); H – Basal Tulare tuff of Obradovich et al. (1978); I – Tuff SW-D of Perkins (1987).

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37 (1972) suggests that, in fact, he may have establis hed informal chronozones (NASCN, 2004, Article 75). Despite this, the validity of t hese provincial molluscan stages as any type of chronostratigraphic unit is questionable. Loomis (1990) reviewed and discounted the utility of Addicott’s (1972) California provinc ial molluscan stages as applied to the Etchegoin group due to 1.) the confusion of biostra tigraphic units with informal chronostratigraphic and lithostratigraphic nomencla ture; 2.) taxa comprising Addicott’s (1972) stages are environmentally controlled and la rgely endemic to the SJB; 3.) age resolution of these faunas is poorly constrained; a nd 4.) occurrences of some key taxa used to define Addicott’s (1972) molluscan stages e xtend beyond their defined stratigraphic boundaries in various Coalinga locali ties not investigated by Addicott (1972). As a consequence, Loomis (1990) discounted the utility of Addicott’s (1972) California provincial molluscan stages outside of t he immediate Coalinga region and felt that they could only be applied within the Coalinga region with caution. The “Jacalitos” stage of Addicott (1972) has no str atotype designated in violation of NASCN (2004) Article 67 and is thus invalid. Ad dicott (1972) defined the top of the “Jacalitos” stage as the boundary between biostrati graphic zonules 10 and 11 of Adegoke (1969) which lies within the middle Etchegoin Forma tion as correlated and mapped by Adegoke (1969) and Clark and Loomis (1992) and mark s the boundary between the lower and upper members of the Etchegoin Formation in thi s study. Addicott (1972) defined the “Jacalitos” provincial mollusc based on 1.) the restricted occurrences of Nassarius salinaensis Turritella cooperi forma nova and Lyropecten terminus 2.) the stratigraphically highest occurrences in California of Trophosycon Lucinisca and the echinoid Astrodapsis and 3.) the stratigraphically lowest occurrences of Patinopecten Lituyapecten Clinocardium meekianum Forreria belcheri and the echinoid Dendraster Nassarius salinaensis and Lituyapecten are taxa from central coastal California basins and have not been reported from SJB faunas (see the exhaustive faunal lists in Hall, 2002, Appendix A-10-A12). Lyropecten terminus and Trophosycon have both been reported above the upper boundary of the “Jacalitos” stage b y Adegoke (1969) and are thus not definitive of the “Jacalitos” stage. Thus the lack of a definitive “Jacalitos” stage stratotype, correlation of the upper “Jacalitos” st age boundary with the lower-upper Etchegoin Formation boundary, and taxonomic ranges of definitive taxa that extend beyond the stage boundary negate the utility and va lue of this chronostratigraphic unit. The “Etchegoin” and “San Joaquin” stages also lack definitive stratotypes (Addicott, 1972, p. 17): Well-known difficulties in recognizing these units from molluscan data from other California Pliocene basins suggests that thei r utility as separate units is largely restricted to biostratigraphic correlation within the San Joaquin basin. Reference sections for this part of the Pliocene ar e the Jacalitos Hills south of Coalinga (lower part) and in the North Dome of n earby Kettleman Hills (upper part).

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38 There are no further explanations of the stratigrap hic sections “lower part” and “upper part” reference. Addicott’s (1972) questioned util ity of these stages and vague stratotype definitions violates NASCN (2004) Article 78 and th us leaves questions of their value. Further, Addicott (1972) failed to specify either d efinitive “Etchegoin”or “San Joaquin”stage faunas therefore violating NASCN (2004) Artic le 66-67 and 76. Therefore both the “Etchegoin” and “San Joaquin” stages are invalid. Lindberg (1984, footnote a) in the Correlation of S tratigraphic Units of North America chart for central California (COSUNA) compo unded the problem of the age of the “Jacalitos” stage by assigning it to the late M iocene at ~8.7-6.0 Ma based on a compromise of unresolved conflicting numerical ages from a tuff located near the top of the Etchegoin Formation in the Kettleman Hills (loc ality 052802.08, Appendix A). This tuff was geochemically correlated to the Lawlor Tuf f of the Sonoma Volcanics, with a KAr date of 3.960.18 Ma, by United States Geologica l Survey (“USGS,” 1976, p. 79, incorrectly given as 4.1 Ma in Lindberg, 1984, foot note a, although correctly page-cited; now revised to 4.831 Ma, McLaughlin et al., 2004) whereas Obradovich et al. (1978) reported a zircon fission track, “FT,” date of 7.0 1.2 Ma for the same tuff. As a consequence of this chronostratigraphic conflict, e ditorial compromise, and mistake in the USGS (1976, p. 79) age date as cited by Lindberg (1 984, footnote a), the correlations of the Etchegoin group in the Coalinga region and adja cent areas by Blaisdell (1984) likewise have ages assigned to the base of the lowe r Etchegoin group Jacalitos Formation or undifferentiated Jacalitos-Etchegoin formations (as Etchegoin Formation) too old at ~7 Ma and the top of the Etchegoin Formation too old a t 4.6 Ma. However, the COSUNA correlations have been the source of Etchegoin grou p chronostratigraphic relationships and numerical age dates used in many subsequent stu dies (e.g., Loomis, 1990; Reid, 1995; Prothero, 2001).Age of the Base of the Tulare Formation Miller (1999) identified a non-marine facies of the San Joaquin Formation exposed in a tuff bed correlative with the Putah Tu ff member of the Sonoma Volcanics (~3.4 Ma, Sarna-Wojcicki, 1976, 2002; Sarna-Wojcicki et al., 1979, 1991, pers. comm., 2002; now 3.270.03, Sarna-Wojcicki, 2005) and adjo ining strata in Arroyo Estrecho, northeast flank of Kettleman Hills Middle Dome, as Tulare Formation based on a suite of freshwater molluscs recovered from the exposure. H owever, as documented by Arnold and Anderson (1910), Pilsbry (1934, 1935), Woodring et al. (1940), Taylor (1966), and this study, these taxa range throughout the uppermo st Etchegoin and San Joaquin Formations and thus cannot provide the degree of st ratigraphic precision he inferred. However, based on his interpretation, Miller (1999) informally established the base of the Tulare (NASCN, 2004 Article 4a5, 22e) in Arroyo Est recho with an assigned age of ~3.4 Ma Using a similar approach, Miller (1999) corre lated a tuff correlated to the Nomlaki Tuff member of the Tehama and Tuscan Formations (3. 3-3.4 Ma, Sarna-Wojcicki, 1976; Sarna-Wojcicki et al., 1979, 1991; Sarna-Wojcicki, 2002, pers. comm) exposed in a nonmarine lower San Joaquin facies at La Salida, eastcentral flank of Kettleman Hills

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39 Middle Dome and ~3 km south of Arroyo Estrecho, as b asal Tulare Formation. However, Miller (1999) correlated the tuff in Arroyo Doblega do, ~12 km north of Arroyo Estrecho on the east-central flank of the Kettleman Hills No rth Dome, and also correlative with the Nomlaki Tuff (Sarna-Wojcicki, 1976; Sarna-Wojcicki et al., 1979, 1991; Sarna-Wojcicki, 2002, pers. comm), and contiguous strata, as correl ative to the San Joaquin Formation. Consequently, Miller (1999) interpreted these three outcrops as demonstrative of a diachronous base for the Tulare Formation. Woodrin g et al. (1940) described the geology of the San Joaquin and Tulare Formations in the Ket tleman Hills in detail and firmly established the Tulare as overlying the San Joaquin It is thus evident that Miller (1999) misinterpreted the stratigraphic position of non-ma rine facies present within the San Joaquin Formation and mis-correlated the sections i n Arroyo Estrecho and La Salida to the Tulare Formation. Therefore, there is no suppo rt for the base of the Tulare Formation at ~3.4 Ma as proposed by Miller (1999). Late Neogene Biostratigraphy of the SJB The Late Miocene stratigraphy of central and southe rn California is well known and has been extensively studied (e.g. Bagg, 1905; Martin, 1912; Louderback, 1913; Hanna, 1928; Galliher, 1931; Barbat and Johnson, 19 34; Kleinpell, 1938; Siegfus, 1938; Stewart, 1946; Bramlette, 1946; Woodring and Bramle tte, 1950; Murata and Randall, 1975; Graham and Williams, 1985; White, 1990; Reid and McIntyre, 2001). In coastal basins, the Late Miocene Monterey Formation is over lain by the latest Miocene Santa Margarita basin-margin facies and latest Miocene-ea rly Pliocene basinal Sisquoc Formation, and their correlatives (Woodring and Bra mlette, 1950). The age of the Monterey-Sisquoc contact in the Santa Maria Basin b ased on diatom biostratigraphy is at 6.0 Ma (Barron and Rameriz, 1992, fig. 9) although it appears to be diachronous given ages as old as 7 Ma for the contact in some areas ( Dumont and Barron, 1995). In the SJB, the Monterey is overlain by the Reef Ridge and Santa Margarita formations that represent basinal and shallow-marine, basin-margin facies, respectively (Reid, 1995). The basin was connected to the Pacific Ocean throug h the Santa Maria Basin and Priest Valley Strait during the Late Miocene (Galehouse, 1 967; Dorhenwend, 1979; Harris, 1987; Loomis, 1990; Reid, 1995) and Sisquoc-Reef Ri dge and Santa Margarita sediments were deposited in both basins. Siegfus (1938) note d the correlation of the Reef Ridge Formation at its type area as approximating the “ca ving blue shale” described by Goudkoff (1934) in the subsurface of the Kettleman Hills. Goudkoff (1934) placed the Miocene-Pliocene boundary at the contact of the “ca ving blue shale” and the overlying Jacalitos Formation based on benthic foraminifera. Kleinpell (1938) correlated the lowermiddle Reef Ridge Formation exposed in Tar Canyon, Kreyenhagen Hills, as correlative to the lower-middle Delmontian California benthic f oraminifera stage (6.5-4.950.15 Ma, Blake, 1991). Buehring (1992) placed the Reef Ridge-Etchegoin For mations contact in the subsurface of the South Belridge and Elk Hills oil fields at just above the base of the Thalassiosira oestrupii diatom zone of Barron (1981) and Barron and Baldau f (1986)

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40 which is correlative with and superceded by North P acific Diatom zone NPD 7Bb of Maruyama (2000; 5.49 to 3.53-3.95 Ma, Maruyama and Shiono, 2003). Nilsen and Wylie (1996) placed the base of the Etchegoin group is at the Miocene-Pliocene boundary at ~5.3 Ma based upon diatom assemblage biozonation. I n the subsurface of southeastern Lost Hills oil field (Fig. 2.1, location G) the Ree f Ridge Formation-Etchegoin group boundary is generally correlated at the base of the “D” sand, a thin, fine-grained sand marking the lithologic contact between underlying R eef Ridge diatomites and overlying fine-grain clastic rocks of the Etchegoin group (e. g. Fossum and Fredrich, 2000). However the Miocene-Pliocene boundary in the subsur face of southeastern Lost Hills oil field is located in the Reef Ridge Formation at the “G” electric log marker, 150 m below the "D” sand, based on benthic foraminifera biostra tigraphy (unpublished data). The first occurrence (FO) of the diatom Thalassiosira praeoestrupii (FO 4.8-4.9 Ma, Maruyama and Shiono, 2003) in floras from the subsurface of southeastern Lost Hills oil field is in the basal Etchegoin group "D” sand. Thus depositi on of the “D” sand is coincident with the eustatic lowstand at the Jacalitos-Etchegoin Fo rmations boundary (~4.8 Ma, Fig. 2.4) suggesting deposition of the “D sand” as a distal l owstand fan. Further, it is suggested that the uppermost Reef Ridge Formation in the cent ral SJB is the correlative basinal facies of the Jacalitos Formation and undifferentia ted lower Etchegoin group strata on the western basin margin. Outside of the Coalinga region, the Jacalitos Form ation is only recognized in outcrop the Bacon Hills (Addicott, 1972), ~100 km so utheast of the Kettleman Hills, and in Muddy Creek (Pack, 1920; Hoots, 1930; this study ), in foothills of the San Emigdio Mountains ~175 km southeast of the Kettleman Hills ( Fig. 2.1), where the presence of the bivalve Zirfaea dentata in the fauna from locality 053102.01, unknown abov e the middle Jacalitos (Arnold, 1909; Arnold and Anderson, 1910; Adegoke, 1969), provides correlation to the Jacalitos section in the Coaling a region. The interval from middle Etchegoin through lower San Joaquin formations in t he subsurface of Lost Hills Field cannot be resolved by diatom stratigraphy beyond th e top of the Etchegoin Formation lying within NPD 7Bb-NPD 9 (2.61/2.68-2.0 Ma, Maruy ama, 2000). Buehring (1992) concluded that the top of the top of the Etchegoin Formation probably lies within NPD 7Bb thus >3.53-3.95 Ma. The top of the Etchegoin Formation falls early Nort h in the American land mammal Blancan III stage (Repenning, 1987; 4.0-3.1 Ma, Woodburne and Swisher, 1995; ~4.1-3.0 Ma, Bell et al., 2004). The base of the Bl ancan III stage is defined by the immigration from Asia and first appearance datum (F AD) in the Pacific Northwest fossil record of the muskrat Pliopotamys (Repenning, 1987) at ~4.2 Ma (Repenning et al., 199 5, though without reference to the method of determina tion). Repenning et al. (1995) reported Pliopotamys from the uppermost Etchegoin Formation in the Kett leman Hills (as Dolomys and subsequently reidentified as Pliopotamys ; see the discussion in Bell et al., 2004, and sources cited therein) stratigraphically below a tuff in the upper Littorina zone correlated with the Lawlor Tuff of the Sonoma Volca nics (locality 052802.08, Appendix A; 25 m below the top of the Etchegoin Formation) d ated by tephrochronology at 4.10.2

PAGE 56

41 (Sarna-Wojcicki, 1991). Whereas the correlation of locality 052802.08 to the Lawlor Tuff is dubious (discussed below), the age correlat ion of Pliopotamys in the Kettleman Hills uppermost Etchegoin Formation is credible. R epenning et al. (1995) reported the first occurrence of Pliopotamys in the Sacramento River Basin, ~300 km north of the Coalinga region, at 4.1 Ma, though again without me ntion of the age determination method. The first occurrence of Pliopotamys in the White Bluffs, Blufftop, Hagerman, and Glenns Ferry faunas of the Snake River drainage of eastern Washington and western Idaho is upsection from the Cochiti subchron of the Gilbert Chron (Repenning, 1987; top of the Cochiti subchron dated at 4.187 Ma, Ogg and Smith, 2004). Lindsay et al. (1984) dated the earliest White Bluffs fauna at3.8 Ma base d on magnetostratigraphy (~4 Ma based on the magnetochronologic scale of Ogg and Sm ith, 2004). Likewise, in the Glenns Ferry fauna the earliest occurrence of Pliopotamys (7 m above the Cochiti subchron; Neville et al., 1979; Repenning et al., 1 995) was estimated at 3.8 Ma (~4 Ma based on the magnetochronologic scale of Ogg and Sm ith, 2004). Whereas Lindsay et al. (1984) disputed the magnetostratigraphy of the Glen ns Ferry fauna of Neville et al. (1979), they corroborated the correlation of Nevill e et al. (1979). Thus evidence supports the probable immigration of Pliopotamys to North America at ~4.2 Ma suggested by Repenning (1987) with dispersal into the Snake Rive r drainage and SJB by ~4.0 Ma. Therefore the age of the top of the Etchegoin Forma tion is at ~4 Ma, based on the occurrence of Pliopotamys in the upper Littorina zone, and coincident with eustatic lowstand of sequence TB 3.6 of Haq et al. (1988; se quence boundaries of TB 3.6 at 3.95 Ma and 3.21 Ma, Wornardt et al., 2001; Bowersox, 20 05). Woodburne and Swisher (1995) noted that the Blancan III dispersal of microtine rodents (Repenning, 1987; Repenning et al., 1990; R epenning 2003) corresponds to eustatic regression and sea level lowstand sequence TB 3.6 of Haq et al. (1988) at 4 Ma (Wornardt et al., 2001). The time span of the Blan can III includes the depositional period of the lower San Joaquin Formation (Woodburne and S wisher, 1995; Bell et al., 2004). The following Blancan IV is based on provincial fau nal changes in the Snake River basin and Great Plains (Repenning, 1987) and may correspo nd to sea-level lowstand of sequence TB 3.7 of Haq et al. (1988) (Woodburne and Swisher, 1995) dated at 3.21 Ma (Wornardt et al., 2001). Repenning (1987, 2003) re ported the microtine rodent Mimomys ( Cosomys ) primus (range 3.7-3.0 Ma, Repenning, 2003) from the Pecten zone of the basal upper San Joaquin Formation. Thus the age range of the lower San Joaquin Formation is 3.7-3 Ma. The top of the Etchegoin group, the San Joaquin-Tulare contact, occurs in the late Pliocene Neodenticula koizumii diatom zone (NPD 9, 2.61-2.68 to 2 Ma, Maruyama and Shiono, 2003) determined from diatom floras fro m the subsurface of southeast Lost Hills oil field. The last occurrence of Thalassiosira antiqua (LO in lower Chron C2r2 ~2.45 Ma, Olschesky and Laws, 2002) in the subsurfac e of southeast Lost Hills oil field is 70 m below the top of the San Joaquin Formation and thus the top of the San Joaquin Formation at <2.45 Ma and 2 Ma. The average depositional rate for the 760 m interval from the “D” sand to the LO of Thalassiosira antiqua is .32 m/kyr. At this depositional rate, the interval above the LO of Thalassiosira antiqua represents deposition over a

PAGE 57

42 period of ~220 kyr and places the top of the San Joa quin Formation at ~2.23 Ma. Sr Isotopic Numerical Age Dates Strontium isotopic (87Sr/86Sr) numerical age dates have been determined from Etchegoin group fossils from outcrops in the Kettle man Hills and Kreyenhagen Hills (Loomis, 1990, 1992b) and from cores from the subsu rface of Elk Hills oil field, Kern County (Mahan et al., 2001). Loomis (1988, 1990, 1 992b) reported Late Miocene87Sr/86Sr age dates 7.5 Ma from oysters, pectinids, and a cirriped from the Etchegoin group in the Kreyenhagen Hills and Kettleman Hills deriving the age dates from the87Sr/86Sr curve of Koepnick et al. (1985), one of the earl iest studies. Loomis (1988, 1990, 1992b) considered all dates >7.5 Ma to be spurious or questionable. First of all, Pliocene87Sr/86Sr age dates are problematic due to the uncertainty inherent in the late Neogene87Sr/86Sr seawater curve and variation in the ratios intro duced from freshwater in nearshore environments, the setting of the SJB. Fo r example, Farrell et al. (1995) published an improved 87Sr/86Sr reference curve for the late Neogene seawater, b ut they noted that minimum age date errors range from 0.60 Ma for the steepest parts of the curve (6-5 Ma and 2-0 Ma) to 2.03 Ma for the flat test part of the curve at 5-2 Ma (Farrell et al., 1995), the portion that encompasse s the Etchegoin group. Farrell et al.’s (1995) data are presently the best available becaus e for the 0-7 Ma interval because their data scatter less than alternative data and the int erlaboratory bias applicable to Farrell et al.’s (1995) data has been independently quantified (McArthur et al., 2001). However, the uncertainty of 2.03 Ma for the 3 Myr period of 5-2 Ma makes any 87Sr/86Sr from this period inherently uncertain. Second, Bryant et al (1995) demonstrated how the re liability of 87Sr/86Sr numerical age dates derived from marine molluscs are measurab ly affected by brackish-water conditions and that the direction of error is towar d older ages. In particular the spurious87Sr/86Sr age dates >7.5 Ma reported by Loomis (1988, 1990 1992b) were likely reflecting hyposaline environments (Bryant et al., 1995). The taxa analyzed for 87Sr/86Sr values by Loomis (1988, 1990, 1992b), such as Mytilus Ostrea Mya Anadara, pectens, and Balanus are characteristic of brackish-water environments within the Etchegoin group in the Coalinga region (e.g., Woodring et al. 1940; Adegoke, 1969; Stanton and Dodd, 1970, 1976; Loomis, 1988, 1990; Bowersox, 200 5). In calculating the strontium isotopic mixing of fresh and saline water in the Pl iocene SJB, Bryant et al (1995) assumed that 1.) average Sr concentration in Plioce ne seawater was the same as the modern seawater Sr concentration, 2) Late Miocene-E arly Pliocene 87Sr/86Sr of the ocean was ~0.7090 (from Hodell et al., 1990), and 3.) the average riverine influx to the Pliocene SJB was the same as modern rivers draining into the basin with 0.09 ppm Sr and 87Sr/86Sr of 0.7073 (from Ingram and Sloan, 1992, table 1). Bryant et al. (1995) concluded that when the 87Sr/86Sr measurements from marginal marine invertebrate t axa of Loomis (1990, 1992b) are converted to paleosalinity that h yposaline conditions are demonstrated in the Etchegoin Formation and molluscs may have li ved in water of <5‰ salinity. Mahan et al. (2001) derived 87Sr/86Sr age dates from bivalves recovered from the

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43 subsurface of the Elk Hills oil field. Based on th e seawater Sr curve of Farrell et al. (1995), an early Pliocene age of 3.751.55 Ma was d etermined from an oyster shell recovered from the subsurface First Mya zone, uppermost San Joaquin, and middle Miocene to early Pliocene ages of 5.1-13.9 Ma from Mya sp. shells recovered from the Third Mya zone, middle San Joaquin (Mahan et al., 2001). M ahan et al. (2001) noted some diagenetic alteration of the Mya sp. shells from the Third Mya zone. Neither the87Sr/86Sr age dates reported by Loomis (1990, 1992b) nor t hose of Mahan et al. (2001) represent valid age dates from the strata sampled. However, in the subsurface of the Elk Hills oil field, Berryman (1973), Maher (1975), Ten ison (1989), and Buehring (1992) recognized that the Etchegoin and San Joaquin secti ons represented deposition in shallow-marine to brackish-water lagoonal waters an d adjacent marginal-marine to freshwater environments. Like Loomis (1988, 1990, 1992b), Mahan et al. (2001) analyzed characteristic brackish-water taxa, oyster and Mya for 87Sr/86Sr values. Therefore, the early Pliocene and Miocene 87Sr/86Sr numerical age dates of Mahan et al. (2001) also are reflective of brackish-water enviro nments inhabited by the source taxa and could readily supply less than reliable numeric al ages using the Sr dating technique Tephrachronologic and Numerical Age Dates Numerical age dates have been determined from Etche goin group tephras by four analytical techniques: zircon fission tracks, K-Ar, 39Ar/38Ar, and tephrochronology (Fig. 2.5). The first numerical age date reported from a n Etchegoin group tuff was by Obradovich (1975, in Repenning and Tedford, 1977) f or the lower San Joaquin tuff in Arroyo Doblegado (locality 030202.01b; Appendix A, G), east-central flank of Kettleman Hills North Dome, which was given as 4.3 Ma though without mention of the analytical technique used to determine this date nor error ran ge. Trace elements measured by neutron-activation analysis of glass recovered from a water-laid tuff near the top of the Etchegoin in the Kettleman Hills (locality 052802.0 8, Appendix A) were used to geochemically correlate the Kettleman Hills tuff to the Lawlor Tuff of the Sonoma Volcanics, then dated at 3.960.18 Ma (Sarna-Wojcic ki, 1976; now 4.831 Ma, McLaughlin et al., 2004), that is interbedded with terrestrial deposits at several localities in the east-central Coast Ranges of California to t he north (USGS, 1976). Obradovich et al. (1978) published additional numerical age dates for the Etchegoin group and Tulare in the Kettleman Hills ranging from a zircon fission t rack (FT) date from the basal Tulare of 2.20.3 Ma, an FT date of 4.60.5 Ma and K-Ar date of 4.50.8 Ma for the Arroyo Doblegado tuff, and an FT date of 7.01.2 Ma for th e uppermost Etchegoin Formation tuff (locality 052802.08). Sarna-Wojcicki et al. (1979) and Sarna-Wojcicki et al. (1991) presented tephra correlations for Etchegoin group tuffs including th e Ishi Tuff member of the Tuscan Formation of northern California (2.5 Ma, Sarna-Woj cicki et al., 1991) present near the top of the San Joaquin, correlation of the Arroyo D oblegado tuff with the Nomlaki Tuff member of the Tehama and Tuscan Formations (3.3-3.4 Ma, Sarna-Wojcicki, 1976; Sarna-Wojcicki et al., 1979, 1991; Sarna-Wojcicki, 2002, pers. comm.; Fig. 2.5), and

PAGE 59

44 Figure 2.5. Age spectra of tuffs from Kettleman Hills localit ies 030202.01b (A) and 030202.05 (B) show the effect of excess argon and r esulting old apparent ages (discussed in Appendix G). Comparing the results of these sam ples to the K-Ar age dates of Obradovich et al. (1978) and Loomis (1990a, 1992a) suggests that those dates also show the effect of excess argon.

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45 correlation of a tuff 28 m below the top of the Etc hegoin (locality 052802.08) with the Lawlor Tuff member. Geochemical correlations of ma jor element measured from five tuffs on the Coalinga Anticline were reported by Pe rkins (1987). These correlations were internally inconsistent below a tuff near the top o f the San Joaquin correlated to the Ishi Tuff (Perkins, 1987). Tuffs in the Jacalitos and l ower Etchegoin Formation correlate with tuffs ranging in age from late Miocene to late Plei stocene (Perkins, 1987). Most recently, Loomis (1990, 1992a) reported K-Ar dates from three informally named Etchegoin group tuffs found in Zapato-Chino Canyon in the Kreyenhag en Hills (Fig. 2.5): the Gate tuff, 4.2 0.5 Ma, Deadman tuff, 8.1 0.9 Ma, and Den Har tog tuff, 5.0 0.3 Ma. Loomis (1990, 1992a) noted that the ages of these tuffs we re out of sequence with their relative stratigraphic position and concluded that the Gate tuff age date was too young and that of the Deadman tuff too old. These spurious dates wer e attributed to low K contents due to diagenetic devitrification of the dated glass (Loom is, 1990, 1992a) although the K-Ar dating method has long been known for its inherent inaccuracy (e.g,. Dunham et al., 1968; Fitch et al., 1974). There is a great disparity of ages indicated for th e Etchegoin group by biostratigraphy, tephrochronology, and radiometric methods especially when compared to the popular COSUNA chart even after disregarding th e Sr isotopic age dates. Neither the tuff near the top of the Etchegoin in the Kettleman Hills correlated to the Lawlor Tuff nor the Arroyo Doblegado tuff have been directly age da ted. To verify the age and correlations of Etchegoin group tuffs, samples were collected from four Etchegoin group tuffs from the central Kettleman Hills (Fig. 2.5), two of which were submitted to the University of Nevada, Las Vegas (UNLV) Geochronolog y Laboratory for 40Ar/39Ar age dating (Appendix A, G): an Etchegoin tuff at locali ty 030202.05 lying at a composite stratigraphic level 1580 m above the base of the Et chegoin group (115 m below the top of the Etchegoin), and a lower San Joaquin tuff in Arr oyo Doblegado, localities 030202.01b, lying at a composite stratigraphic level 1975 m abo ve the base of the Etchegoin group (280 m above the top of the Etchegoin). The measur ed age spectra for the two tuffs were discordant (Fig. 2.5, Appendix G), suggestive of ex cess argon with 40Ar/36Ar values of ~320-340. Sample 030202.05 yielded a maximum age of 21.7 Ma and sample 030202.01b yielded a maximum age of 4.99 Ma.Discussion The Etchegoin group chronology established in this study is based on biostratigraphic correlations of diatoms, foraminif era, molluscs, and terrestrial vertebrates. The Reef Ridge-Etchegoin group bounda ry is placed at the MiocenePliocene boundary at ~5.3 Ma based on diatom stratig raphy although benthic foraminiferal biostratigraphy suggests that the upp ermost section of the Reef Ridge Formation in the central SJB may be correlative wit h the basin-margin Jacalitos Formation. The Jacalitos-Etchegoin formations boun dary is at 4.8 Ma based on the FO of the diatom Thalassiosira praeoestrupii Correlation of the Jacalitos Formation between the section at Muddy Creek and the Coalinga region was established by the presence of

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46 Zirfaea dentata in both sections, a bivalve not known to occur abo ve the middle Jacalitos Formation. The FO of the muskrat Pliopotamys in the uppermost Etchegoin Formation Littorina zone suggests the age of the top of the Etchegoin Formation at ~4 Ma coincident with a major eustatic regression in the Pliocene SJ B. The presence of microtine rodent Mimomys ( Cosomys ) primus in the Pecten zone of the basal upper San Joaquin Formation suggests an age range of the lower San Joaquin Form ation is ~4-3 Ma. The age of the San Joaquin-Tulare formations boundary is inferred at ~2.23 Ma from the LO of the diatom Thalassiosira antiqua 70 m below the top of the San Joaquin Formation in the subsurface of the southeastern Lost Hills oil field There is no single reliable method for constructing a chronostratigraphy for the Etchegoin group. Tephrochronology from the Etchegoin group is proble matic, although it may be representative of the age of strata if corro borated by other evidence. Biostratigraphy is the best available corroborative evidence for developing a chronostratigraphic framework for the Etchegoin gro up. 87Sr/86Sr age are problematical both from the inherent uncertainty of Pliocene age dates and brackish environments. The age spectra of the tuffs from localities 030202.01b and 030202.05 (Fig. 2.5) in themselves did not provide unequivocal dates for th ese rocks, however they did provide a basis for interpreting the previous K-Ar dates from the Etchegoin group of Obradovich et al. (1978) and Loomis (1990, 1992a) as likely affec ted by excess argon and are thus spurious. The FT dates of Obradovich et al. (1978) from the lower San Joaquin, 4.60.5 Ma and confirmed by a spurious K-Ar age date, and 7 .0 1.2 Ma from the uppermost Etchegoin in the Kettleman Hills, are both too old to be representative of the age of the strata and thus are detrital grains. An internally consistent chronostratigraphic model can be constructed for the Etchegoin group by combining biostratigraphy, uncon formities associated with eustatic cycles of sea-level lowstands recorded in the rock record, as well as tephra correlations and numeric age dates where they can be independent ly corroborated. Biostratigraphy constrains the base of the Etchegoin group and Jaca litos Formation to the MiocenePliocene boundary at 5.33 Ma and the top of the Jac alitos at 4.8 Ma. The average combined Jacalitos-Etchegoin section in the Kreyenh agen Hills is 1695 m with the Jacalitos Formation comprising the lower 635 m of t he section (Fig. 2.4). Based on an average rock accumulation rate of 1.2 m/ky for the sequence, an age of ~4.8 Ma is suggested for the top of the Jacalitos Formation (F ig. 2.4) corroborating the biostratigraphic age determination. Sea-level lows tand coincident with the onset of upper Etchegoin deposition (Tenison, 1989; Bowersox, 2004 ) correlates to the lowstand of the TB 3.5 3rd-order eustatic cycle in the Gulf of Mexico (Wornar dt and Vail, 1991; Wornardt et al., 2001) at 4.37 Ma (Bowersox, 2004; Chapter 3 ). Using this point to constrain the interval of Jacalitos-lower Etchegoin deposition to ~5.3-4.4 Ma, the calculated average depositional rate for the section again places the end of upper Jacalitos deposition at ~4.8 Ma and the end of the lower Jacalitos deposition at ~5.1 Ma. The estimated age of the top of the Jacalitos approximates the major early P liocene sea-level lowstands identified by Miller et al. (2005) at 4.82 and 4.88 Ma and con sistent with sedimentological and

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47 faunal changes across the Jacalitos-Etchegoin bound ary (Bowersox, 2005; Chapter 6). The top of the overlying Etchegoin Formation has be en placed at ~4 Ma (Nilsen and Wylie Jr., 1996; Miller, 1999). Barbat and Gal loway (1934) noted a fundamental lithologic and faunal change across the boundary be tween the Etchegoin and the overlying San Joaquin (Fig. 2.3). Woodring et al. (1940), Stanton and Dodd (1976), and Loomis (1990) also noted the lithologic change from marine to non-marine rocks and an unconformity between the Etchegoin and San Joaquin consistent with the 3rd-order eustatic lowstand dated in the Gulf of Mexico at 3. 95 Ma (Wornardt and Vail, 1991; Wornardt et al., 2001; Bowersox, 2004; Chapter 3; F ig. 2.4) and placed at 4 Ma by Miller et al. (2005). A ~4 Ma age for the top of the Etche goin is consistent with FO of Pliopotamys in the Littorina zone and is consistent with the base of the North American land mammal Blancan III stage in the uppermost Etch egoin dated at 4.1 Ma (Bell et al., 2004). The base of the North American mammal Blanc an III stage (~4.1-3.0 Ma, Bell et al., 2004) is defined as the immigration from Asia and FAD of Pliopotamys in North American mammalian faunas (Repenning, 1987). Pliopotamys is found in mammalian faunas in the Snake River basin that are well const rained by magnetostratigraphy to 4-3.9 Ma as well as in younger faunas from the Great Plai ns (Repenning, 1987; Repenning et al., 1995). Repenning et al.(1995) place the FAD o f Pliopotamys in the Sacramento River basin at 4.1 Ma. The FAD of Pliopotamys in the SJB is in the uppermost Etchegoin Formation at approximately the level of 0 52802.08 (Bell et al., 2004). If 052902.08 correlates to the Lawlor Tuff of the Sono ma Volcanics (4.831 Ma, McLaughlin et al., 2004) as has been postulated by Sarna-Wojcicki et al. (1979), SarnaWojcicki et al. (1991), and Sarna-Wojcicki (2002, pers. comm.), then the FAD of Pliopotamys in North America is 4.8 Ma. However, despite a substantial number of records of Pliopotamys (Repenning, 1987; Repenning et al., 1995, as Dolomys ; Repenning 2003; Bell et al., 2004, and sources cite d therein), there is none in any western fauna dated older than ~4.1 Ma although there are many other aquatic rodents in western faunas (Repenning et al., 1995) dating to the Blanc an II (~4.62-4.1 Ma, Bell et al., 2004) Further, Pliopotamys is not in the Blancan II White Bluffs fauna dated at 4.3 Ma (Repenning et al., 1995). In order for 052802.08 t o be the Lawlor Tuff, an improbable circumstance would be required where Pliopotamys is found in the SJB and no other western mammalian fauna from the interval 4.8-4.1 M a. Thus correlation of the uppermost Etchegoin tuff (locality 052802.08, Appen dix A) with the Lawlor Tuff (dated at 4.831 Ma, McLaughlin et al., 2004) is not supported. The Pecten zone of Woodring et al. (1940) marks a distinct li thologic and faunal change from the underlying strata (Chapters 4-6) an d defines the boundary between the lower and upper members of the San Joaquin (Woodrin g et al., 1940; Fig. 2.4). The vertebrate fauna reported from the Pecten zone by Repenning (1983) places the age of the lower San Joaquin as ~4 >3 Ma. When compared with thickness of the underlying lower San Joaquin section and the age of the Arroyo Doblegado Nomlaki Tuff (3.3-3.4 Ma, Sarna-Wojcicki, 1976; Sarna-Wojcicki et al., 19 79, 1991; Sarna-Wojcicki, 2002, pers. comm.; Fig. 2.5), the average depositional ra te for the section places they

PAGE 63

48 lower-upper San Joaquin boundary at ~3.1 Ma and with in the age range constrained by the Pecten zone vertebrate fauna (Repenning, 1983). Thus, wi th the constraints on the age of the Pecten zone and the top of the Etchegoin within the Blanc an III, the correlation of the Arroyo Doblegado tuff with the Nomlaki tuff is probable. A tuff at the base of the Tulare Formation in the K ettleman Hills North Dome was FT dated at 2.2 0.3 Ma by Obradovich et al. (1978; Fig. 2.5) and a tuff near the top of the San Joaquin Formation in the Kettleman Hills No rth Dome is geochemically correlative with the Ishi Tuff in northern Californ ia dated at 2.5 Ma (Sarna-Wojcicki et al., 1979, 1991; Sarna-Wojcicki, 2002, pers. comm.; Fig. 2.5). These age dates are consistent with the diatom stratigraphy from the su bsurface of southeastern Lost Hills oil field (Fig. 2.4) and constrain the age of the San J oaquin-Tulare boundary to ~2.2 Ma. The San Joaquin is overlain by lacustrine rocks of the lower Tulare (Woodring et al. 1940) and the boundary represents the final tectoni c closing of the Priest Valley Strait during the latest Pliocene (Loomis, 1990; Bowersox, 2004, 2005; Chapter 3, 6). The average rock accumulation rate for the San Joaquin section based on the age for the base of the Tulare (~2.2 Ma) and the correlation of the A rroyo Doblegado tuff with the Nomlaki Tuff (3.3 Ma) is ~0.4 m/kyr or ~1.8 Ma for Sa n Joaquin deposition. This places the Etchegoin-San Joaquin boundary again at ~4 Ma co nsistent with the methods above. Conclusions1.The lithostratigraphic, biostratigraphic, and chr onostratigraphic data from outcrop and the subsurface support a Pliocene age for the Etche goin group. 2.Chronostratigraphic dating techniques by radiomet ric and tephra correlation, have a mixed record of accuracy and are best considered wi th corroborating evidence of age. K-Ar and 40Ar/39Ar age dating have both presented spurious age date s due to excess Ar in the materials analyzed. 3.87Sr/86Sr age dates are inaccurate due to their sensitivit y to brackish water and the ambiguity of the late Neogene 87Sr/86Sr seawater reference curve. In the San Joaquin Basin, 87Sr/86Sr ratios appear to largely reflect paleosalinity. 4.The age of the Etchegoin group is constrained at 5.3-2.2 Ma. Within the Etchegoin group, the top of the lower Etchegoin is well const rained at 4.4 Ma, top of the upper Etchegoin at 4 Ma, and the top of the lower San Jo aquin at 3.1 Ma. The top of the lower Jacalitos is estimated at 5.1 Ma and top of t he upper Jacalitos at 4.8 Ma. ReferencesAddicott, W.O., 1972, Provincial middle and late Te rtiary molluscan stages, Temblor Range, California, in Stinemeyer, E.H., and Church, C.C., Proceedings of the Pacific Coast Miocene Biostratigraphic Symposium: P acific Section, Society of Economic Paleontologists and Mineralogists, p. 1-26 4 pl. Adegoke, O.S., 1969, Stratigraphy and paleontology of the marine Neogene formations of the Coalinga region, California: University of Cali fornia, Publications in Geological Sciences, v. 80, 241 p., 13 pl.

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49 Anderson, F.M., 1905, A stratigraphic study in the Mount Diablo region of California: Proceedings of the California Academy of Sciences, 3rd Series, v. 2, p. 155-248. Anderson, F.M., 1908, A further stratigraphic study in the Mount Diablo Range of California: Proceedings of the California Academy o f Sciences, 4th Series, v. 3, p. 1-40. Arnold, R., 1909, Paleontology of the Coalinga dist rict, Fresno and Kings Counties, California: United States Geological Survey Bulleti n 396, 173 p., 30 pl. Arnold, R., and Anderson, R., 1910, Geology and oil resources of the Coalinga district, Fresno and Kings Counties, California: United State s Geological Survey Bulletin 398, 354 p. Bagg, R.M., Jr., 1905, Miocene foraminifera from th e Monterey Shale of California, with a few species form the Tejon Formation: United Stat es Geological Survey Bulletin 268, 78 p., 11 pl. Barbat, W.F., and Galloway, J., 1934, San Joaquin C lay, California: American Association of Petroleum Geologists Bulletin, v. 18 p. 476-499. Barbat, W.F., and Johnson, F.L., 1934, Stratigraphy and foraminifera of the Reef Ridge Shale, upper Miocene, California: Journal of Paleon tology, v. 8, p. 3-17,1 pl. Barron, J.A., 1981, Late Cenozoic diatom biostratig raphy and paleoceanography of the middle-latitude eastern North Pacific, Deep Sea Dri lling Project Leg 63, in Yeats, R.S., Haq, B.U., Barron, J.A., Bukry, D., Crouch, J ., Denham, C., Douglas, A.G., Grechin, V.I., Leinen, M., Niem, A., Verma, S.P., P isciotto, K.A., Poore, R.Z., Shibata, T., and Wolfart, R., eds., Initial Reports of the Deep Sea Drilling Project, Volume 63: Washington D.C., United States Governmen t Printing Office, p. 507538. Barron, J.A., and Baldauf, J.G.,1986, Diatom strati graphy of the lower Pliocene part of the Sisquoc Formation, Harris Grade section, Califo rnia: Micropaleontology, v. 32, p. 357-371, 3 pl. Barron, J.A., and Rameriz, P.C., 1992, Diatom strat igraphy of selected Sisquoc Formation Sections, Santa Maria basin, California: United States Geological Survey Open File Report 92-197, 23 p. Bartow, J.A., 1991, The Cenozoic evolution of the S an Joaquin Valley, California: United States Geological Survey Professional Paper 1501, 40 p. Bell, C.J., Lundelius Jr., E.L., Barnosky, A.D., Gr aham, R.W., Lindsay, E.H., Ruez Jr., D.R., Semken Jr., H.A., Webb, S.D., and Zakrzewski, 2004, The Blancan, Irvingtonian, and Rancholabrean mammal ages, in Woo dburne, M.O., ed., Late Cretaceous and Cenozoic Mammals of North America: N ew York, Columbia University Press, p. 232-314. Berryman, W.M., 1973, Lithologic characteristics of Pliocene rocks cored at Elk Hills, Kern County, California: United States Geological S urvey Bulletin 1332D, 56 p.

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50 Blaisdell, R.C., 1984, North Kettleman Hills, Colum n 15-19, in Lindberg, F.A., ed., Central California Region, Correlation of Stratigra phic Units of North America (COSUNA) Project: Tulsa, OK, American Association of Petroleum Geologists, 1 pl. Blake, G.H., 1991, Review of the Neogene biostratig raphy and stratigraphy of the Los Angeles Basin area – relation to plate tectonics, i n Biddle, K.T., ed., Active Margin Basins: American Association of Petroleum Ge ologists Memoir 52, p. 135-184.Bowersox, J.R., 2003, Pliocene age of the Etchegoi n Group, San Joaquin Basin, California [abstract]: American Association of Petroleum Geolo gists, Search and Discovery Article #90014,Bowersox, J.R., 2004. Late Neogene Paleobathymetry, Relative Sea Level, and Basin Margin Subsidence, Northwest San Joaquin Basin, Cal ifornia. American Association of Petroleum Geologists, Search and Dis covery Article 30029,Bowersox, J.R., 2005, Reassessment of extinction pa tterns of Pliocene molluscs from California and environmental forcing of extinction in the San Joaquin Basin: Palaeogeography, Palaeoclimatology, Palaeoecology, v. 221, p. 55-82. Bramlette, M.N., 1946, The Monterey Formation of Ca lifornia and the origin of its siliceous rocks: United States Geological Survey Pr ofessional Paper 212, 57 p. Bryant, J.D., Jones, D.S., and Mueller, P.A., 1995, Influence of freshwater flux on 87Sr/86Sr chronostratigraphy in marginal marine env ironments and dating of vertebrate and invertebrate faunas: Journal of Pale ontology, v. 69, p. 1-6. Buehring, R.L., 1992, Paleoenvironments, sedimentar y sequences, and structural history of the upper Miocene and Pliocene Etchegoin and San Joaquin Formations, southwest margin San Joaquin Basin, California [MS thesis]: Austin, Texas, University of Texas at Austin, 133 p. Dorhenwend, J.C., 1979, Provenance and paleocurrent s of the northern Paso Robles Formation, Monterey County, California, in Graham, S.A., ed., Tertiary and Quaternary Geology of the Salinas Valley and Santa Lucia Range, Monterey County: California: Pacific Section Society of Eco nomic Paleontologists and Mineralogists, Guidebook 4, p. 77-82. Dumont, M.P., and Barron, J.A., 1995, Diatom biostr atigraphy of the Sisquoc Formation in the Santa Maria Basin, California, and its paleo cenaographic and tectonic implications: United States Geological Survey Profe ssional Paper 1995K, 17 p. Dunham, K.C., Fitch, F.J., Ineson, P.R., Miller, J. A., and Mitchell, J.G., 1968, The geochronological significance of Argon-40/Argon-39 Age determinations on White Whin from the Northern Pennine Orefield: Proc eedings of the Royal Society of London, Series A, Mathematical and Physi cal Sciences, v. 307, p. 251-266.

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51 Farrell, J.W., Clemens, S.C., and Gromet, L.P., 199 5, Improved chronostratigraphic reference curve of late Neogene seawater 87Sr/86Sr: Geology, v. 23, p. 403-406. Fitch, F.J., Forster, S.C., and Miller, J.A., 1974, Geological time scale: Reports on Progress in Physics, v. 37, p. 1433-1496. Fossum, A.F., and Fredrich, J.T., 2000, Constitutiv e models for the Etchegoin Sands, Belridge Diatomite, and overburden formations at th e Lost Hills oil field, California: Albuquerque, New Mexico, Sandia Nationa l Laboratories, Sandia Report SAND2000-0827, 34 p. Galehouse, J.S., 1967, Provenance and paleocurrents of the Paso Robles Formation, California: Geological Society of America Bulletin v. 78, p. 951-978, 1 pl. Galliher, E.W., 1931, Stratigraphic position of the Monterey Formation: Micropaleontology Bulletin, v. 2, p. 71-74. Gester, G.C., and Galloway, J., 1933, Geology of Ke ttleman Hills oil field, California: American Association of Petroleum Geologists Bullet in, v. 17, p. 1161-1193. Giosan, L., 2004, Drilling to investigate extreme e nvironmental changes: EOS, Transactions of the American Geophysical Union, v. 85, p. 179. Goudkoff, P.P., 1934, Subsurface stratigraphy of Ke ttleman Hills oil field, California: American Association of Petroleum Geologists Bullet in, v. 18, p. 435-475. Gradstein, F., Ogg, J., and Smith, A, 2004, A Geolo gic Time Scale, 2004: Cambridge, United Kingdom, The Press Syndicate of the Universi ty of Cambridge, 589 p. Graham, S.A., and Williams, L.A., 1985, Tectonic, d epositional, and diagenetic history of Monterey Formation (Miocene), Central San Joaquin B asin, California: American Association of Petroleum Geologists Bulletin, v. 69 p. 385-411. Hall, C.A. and Loomis, K.B., 1992, Geologic Map of the Kreyenhagen Hills-Sunflower (McLure) Valley Area, Fresno, Kern, Kings, and Mont erey Counties, California: Geological Society of America, Map and Chart Series MCH074, 4 Map Sheets, 17 p. Hanna, G.D., 1928, The Monterey Shale of California at its type locality with a summary of its fauna and flora: American Association of Pet roleum Geologists Bulletin, v. 12, p. 969-983. Haq, B.U., Hardenbol, J., and Vail, P.R., 1988, Mes ozoic and Cenozoic chronostratigraphy and cycles of sea-level change, in Wilgus, C.K., Hastings, B.S., Ross, C.A., Posamentier, H.W., Van Wagoner, J ., and Kendall, C.G. St. C., Sea-level changes; an integrated approach: Society of Economic Paleontologists and Mineralogists, Special Publication 42, p.72-108 Harris, W.M., 1987, Organism interactions and their environmental significance, as exemplified by the Pliocene-Pleistocene fauna of th e Kettleman Hills and Humboldt Basin, California [PhD thesis]: College St ation, Texas, Texas A&M University, 254 p. Hoots, H.W., 1930, Geology and oil resources along the southern border of the San Joaquin Valley, California: United States Geologica l Survey Bulletin 812D, p. 243-332.

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52 Ingram, B.L., and Sloan, D., 1992, Strontium isotop ic composition of estuarine sediments as paleosalinity-paleoclimate indicator: Science, v .255, p. 68-72. Jennings, C.W., 1977, Geologic map of California: C alifornia Division of Mines and Geology, California Geologic Data Map Series, Map 2 scale 1:750,000, 1 sheet. Kleinpell, R.M., 1938, Miocene stratigraphy of Cali fornia: Tulsa, Oklahoma, American Association of Petroleum Geologists, 450 p. Koepnick, R.B., Denison, R.E., Burke, W.H., Hetheri ngton, E.A., Nelson, H.F., Otto, J.B., and Waite, L.E., 1985, Construction of the se awater 87Sr/86Sr curve for the Cenozoic and Cretaceous: supporting data: Chemical Geology (Isotope Geoscience Section), v. 58, p. 55-81. Lindberg, F.A., ed., 1984, Central California Regio n, Correlation of Stratigraphic Units of North America (COSUNA) Project: Tulsa, OK, America n Association of Petroleum Geologists, 1 pl. Lindsay, E.H., Opdyke, N.D., and Johnson, N.M., 198 4, Blancan-Hemphillian land mammal ages and late Cenozoic mammal dispersal even ts: Annual Review of Earth and Planetary Sciences, v. 12, p. 445-488. Loomis, K.B., 1990, Late Neogene depositional hist ory and paleoenvironments of the west-central San Joaquin Basin, California [PhD the sis]: Stanford, California, Stanford University, 594 p. Loomis, K.B., 1992a, New K-Ar ages from tuffs in th e Etchegoin Formation, San Joaquin Basin, California: Isochron/West, v.58, p.3-7. Loomis, K.B., 1992b, New 87Sr/86Sr data from invertebrate macrofossils in the Neoge ne Etchegoin Formation, San Joaquin Basin, California: Isochron/West, v.58, p.1721. Louderback, G.D., 1913, The Monterey Series in Cali fornia: University of California Publications in Geological Sciences v. 7, p. 177241. Mahan, A., Gillespie, J.M., and Horton, R.A., 2001, New strontium isotope ages from invertebrate macrofossils in the San Joaquin Format ion, Elk Hills, California [abstract]: Geological Society of America, Abstract s with Programs, v. 33, no. 3, p. 68. Maher, J.C., Carter, R.D., and Lantz, R.J., 1975, P etroleum geology of Naval Petroleum Reserve No. 1, Elk Hills, Kern County, California: United States Geological Survey Professional Paper 912, 109 p. Martin, B., 1912, Fauna from the type locality of t he Monterey Series in California: University of California Publications in Geological Sciences, v. 7, p. 143-150. Maruyama, T., 2000, Middle Miocene to Pleistocene d iatom stratigraphy of Leg 167, in Lyle, M., Koizumi, I., Richter, C., and Moore, T.C. Jr., eds., Proceedings of the Ocean Drilling Program, Scientific Results, v. 167: College Station, Texas, Ocean Drilling Program, p. 63-110.

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53 Maruyama, T., and Shiono, M., 2003, Middle Miocene to Pleistocene diatom 1-38. biostratigraphy of the northwest pacific at sites 1 150 and 1151, in Suyehiro, K., Sacks, I.S., Acton, G.D., and Oda, M., eds., Procee dings of the Ocean Drilling Program, Scientific Reports, v. 186, p. 1-38. McArthur, J.M., Howarth, R.J., and Bailey, T.R., 20 01, Strontium isotope stratigraphy: LOWESS version 3: best fit to the marine Sr-isotope curve for 0-509 Ma and accompanying look-up table for deriving numerical a ge: journal of Geology, v. 109, p. 155-170. McLaughlin, R.J., Sarna-Wojcicki, A.M., Fleck, R.J. Wright, W.H., Levin, V.R.G., and Valin, Z.C., 2004, Geology, tephrochronology, radio metric ages, and cross sections of the Mark West Springs 7.5' quadrangle, Sonoma and Napa Counties, California: United States Geological Survey Scienti fic Investigations Map 2858, 15 p. 2 map sheets. Merriam, J.C., 1915, Tertiary vertebrate faunas of the north Coalinga region of California: Transactions of the American Philosophi cal Society, New Series, v. 22, no. 3, p. 191-234. Miller, D.D., 1999, Sequence stratigraphy and contr ols on deposition of the upper Cenozoic Tulare Formation, San Joaquin Valley, Cali fornia [PhD thesis]: Stanford, California, Stanford University, 179 p. Miller, K.G., Kominz, M.A., Browning, J.V., Wright, J.D., Mountain, G.S., Katz, M.E., Sugarman, P.J., Cramer, B.S., Christie-Blick, N., a nd Pekar, S.F., 2005, The Phanerozoic Record of Global Sea-Level Change: Scie nce, v. 310, p. 193-1298. Murata, K.J., and Randall, R.G., 1975, Silica miner alogy and structure of the Monterey Shale, Temblor Range, California: United States Geo logical Survey, Journal of Research, v. 3, p. 567-572. Neville, C.A., Opdyke, N.D., Lindsay, E.H., and Joh nson, N.M., 1979, Magnetic stratigraphy of Pliocene deposits of the Glenns Fer ry Formation, Idaho, and its implications for North American mammalian biostrati graphy: American Journal of Science, v. 279, p. 503-526. Nilsen, T.H., 1996, San Joaquin Formation core disp lay, Santa Fe Energy Resources well 9000-14, Midway-Sunset oil field, California, in Ni lsen, T.H., Wylie Jr., A.S., and Gregory, G.J., Geology of the Midway-Sunset Oil Fie ld: American Association of Petroleum Geologists Guidebook, p. 289-301. Nilsen, T.H., and Wylie Jr., A.S., 1996, Etchegoin Formation core display, Santa Fe Energy Resources well 504-23, Midway-Sunset oil fie ld, California, in Nilsen, T.H., Wylie Jr., A.S., and Gregory, G.J., Geology o f the Midway-Sunset Oil Field: American Association of Petroleum Geologists Guideb ook, p. 281-288. Nomland, J.O., 1916a, Relation of the invertebrate to the vertebrate faunal zones of the Jacalitos and Etchegoin Formations in the north Coa linga region, California: University of California Publications in Geology, v 9, p. 77-88, pl.7.

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54 Nomland, J.O., 1916b, Fauna from the lower Pliocene at Jacalitos Creek and Waltham Canyon, Fresno County, California: University of Ca lifornia Publications in Geology, v. 9, p. 199-214, pl. 9-11. Nomland, J.O., 1917a, The Etchegoin Pliocene of mid dle California: University of California Publications in Geology, v. 10, p. 191-2 54, pl. 6-12. North American Commission on Stratigraphic Nomencla ture, 2004, North American Stratigraphic Code: American Association of Petrole um Geologists Bulletin, v. 89, p. 1547-1591. Obradovich, J.D., Naeser, C.W., and Izett, G.A., 19 78, Geochronology of late Neogene marine strata in California [abstract]: Stanford Un iversity Publications in Geological Sciences, v. 14, p. 40-41. Ogg, J.G., and Smith, A.G., 2004, The geomagnetic p olarity time scale, in Gradstein, F., Ogg, J., and Smith, A.G., eds., A Geologic Time Sca le, 2004: Cambridge, United Kingdom, Cambridge University Press, p. 63-86. Olschesky, K.S., and Laws, R.A., 2002, Data report: Pliocene-late Pleistocene diatom biostratigraphic data from ODP Leg 185, Hole 1149A, in Ludden, J.N., Plank, T., and Escutia, C., eds., Proceedings of the Ocean Dri lling Program, Scientific Reports, v. 185, p. 1-31. Pack, R.W., 1920, The Sunset-Midway oil field, Cali fornia, Part 1: geology and oil resources: United States Geological Survey Professi onal Paper 116, 179 p. Pack, R.W., and English, W.A., 1914, Geology and oi l prospects in Waltham, Priest, Bitterwater, and Peachtree Valleys, California with notes on coal: United States Geological Survey Bulletin 581-D, p. 119-160. Perkins, J.A., 1987, Provenance of the upper Miocen e and Pliocene Etchegoin Formation: implications for paleogeography of the Late Miocene of Central California: USGS Open-file Report 87-167, 86 p. Pilsbry, H.A., 1934, Pliocene fresh-water fossils o f the Kettleman Hills and neighboring California oil fields: The Nautilus, v. 48, p. 15-1 7. Pilsbry, H.A., 1935, Mollusks of the fresh-water Pl iocene beds of the Kettleman Hills and neighboring oil fields, California: Proceedings of the Academy of natural Sciences of Philadelphia, v. 86, p. 541-570. Prothero, D.R., 2001, Chronostratigraphic calibrati on of the Pacific Coast Cenozoic; a summary, in Prothero, D.R., Magnetic Stratigraphy o f the Pacific Coast Cenozoic: Pacific Section, Society of Economic Paleontologist s and Mineralogists (Society for Sedimentary Geology), Book 91, p. 377-394. Reed, R.D., and Hollister, J.S., 1936, Chapter III: Northern geosynclinal basin and Coalinga district: American Association of Petroleu m Geologists Bulletin, v. 20, p. 1598-1616.

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55 Reid, S.A., 1995, Miocene and Pliocene depositional systems of the southern San Joaquin basin and formation of sandstone reservoirs in the Elk Hills area, California, in Fritsche, A.E., ed., Cenozoic Paleogeography of the Western United States II: Pacific Section, Society of Economic Paleontologist s and Mineralogists, Book 75, p. 131-150. Reid, S.A., and McIntyre, J.L., Monterey Formation porcelanite reservoirs of the Elk Hills Field, Kern County, California: American Asso ciation of Petroleum Geologists Bulletin, v. 85, p.169-189. Repenning, C.A., 1987, Biochronology of the microti ne rodents of the United States, in Woodburne, M.O., ed., Cenozoic Mammals of North Ame rica: Geochronology and Biostratigraphy: Berkeley, California, Universi ty of California Press, p. 236268. Repenning, C.A., 2003, Mimomys in North America: Bulletin of the American Museum of Natural History, no. 279, p. 469-512. Repenning, C.A., and Tedford, R.H., 1977, Otaroid s eals of the Neogene: United States Geological Survey Professional Paper 992, 93 p., 24 pl. Repenning, C.A., Weasma, T.R., and Scott, G.R., 199 5, The early Pleistocene (latest Blancan-earliest Irvingtonian) Froman Ferry fauna a n history of the Glenns Ferry Formation, Southwestern Idaho: United States Geolog ical Survey Bulletin 2105, 86 p. Sarna-Wojcicki, A.M., 1976, Correlation of late Cen ozoic tuffs in the central Coast Ranges of California by means of traceand minor-e lement chemistry: United States Geological Survey Professional Paper 972, 30 p. Sarna-Wojcicki, A.M., 2005, Chronostratigraphic fra mework for the Sonoma Volcanics and associated sediments, long-term fault displacem ent rates, and areal dispersion of tephra from the source area, central coast range s, California [abstract]: Geological Society of America, Abstracts with Progr ams, v. 37, no. 4, p. 83. Sarna-Wojcicki, A.M., Bowman, H.W., and Russell, P. C., 1979, Chemical correlation of some late Cenozoic tuffs of northern and central Ca lifornia by neutron activation analysis of glass and comparison with x-ray fluores cence analysis: United States Geological Survey Professional Paper 1147, 15 p. Sarna-Wojcicki, A.M., Lajoie, K.R., Meyer, C.E., Ad am, D.P., and Rieck, H.J., 1991, Tephrochronologic correlation of upper Neogene sedi ments along the Pacific margin, conterminous United States: Geological Soci ety of America, The Geology of North America, v. K2, p. 117-140, 1 pl. Siegfus, S.S., 1939, Stratigraphic features of Reef Ridge Shale in southern California: American Association of Petroleum Geologists Bullet in, v. 23, p. 24-44. Stanton, R.J. and Dodd, J.R., 1972, Pliocene cyclic sedimentation in the Kettleman Hills, California, in Rennie, E.W., ed., Guidebook to Geol ogy and Oil Fields, West Side Central San Joaquin Valley: American Association of Petroleum Geologists, Pacific Section, p. 50-58.

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56 Stanton, R.J., and Dodd, 1976, Pliocene biostratigr aphy and depositional environment of the Jacalitos Canyon area, California, in Fritsche, E.A., Ter Best, H., and Wornardt, W.W., eds., The Neogene Symposium: Pacifi c Section, Society of Economic Paleontologists and Mineralogists, p. 85-9 4. Stewart, R., 1946, Geology of Reef Ridge, Coalinga district, California: United States Geological Survey Professional Paper 265C, p. 81-11 5, pl. 9-17. Taylor, D.W., 1965, Summary of North American Blanc an non-marine mollusks: Malacologia, v. 4, p. 1-172. Tenison, J.A., 1989, Biostratigraphy, lithostratigr aphy and paleoenvironment of the Etchegoin and San Joaquin Formations, Buena Vista H ills, California [MS thesis]: Austin, Texas, University of Texas at Austin, 125 p United States Geological Survey, 1976, Correlative late Cenozoic tephra, California and western Nevada: United States Geological Survey Pro fessional Paper 1000, p. 7980. White, L.D., 1990, Stratigraphy and paleocenographi c history of the Monterey Formation at Pt. Ao Neuvo, California, in Garrison, R.E., a nd Greene, H.G., Hicks, K.R., Weber, G.E., and Wright, T.L., eds., Geology and te ctonics of the Central California coastal region, San Francisco to Montere y: American Association of Petroleum Geologists, Pacific Section, Guidebook 67 p. 91-104. Wilson, I.F., 1943, Geology of the San Benito Quadr angle, California: California Journal of Mines and Geology, v. 39, p. 183-270. Woodburne, M.O., and Swisher, C.C., 1995, Land mamm al high-resolution geochronology, intercontinental overland dispersals sea level, climate, and vicariance, in Berggren, W.A., Kent, D.V., Aubrey, M.-P., and Hardenbol, J., Geochronology, time scales and global stratigraphic correlation: Society of Economic Paleontologists and Mineralogists, Special Publication 54, p. 335-365. Woodring, W.P. and Bramlette, M.N., 1950, Geology a nd Paleontology of the Santa Maria District, California: United States Geologica l Survey Professional Paper 222, 185 p. Woodring, W.P., Stewart, R., and Richards, R.W., 19 40, Geology of the Kettleman Hills oil field, California: United States Geological Sur vey Professional Paper 195, 170 p. 56 pl. Wornardt, W.W., and Vail, P.R., 1991, Revision of t he Plio-Pleistocene cycles and their application to sequence stratigraphy and shelf and slope sediments in the Gulf of Mexico: Transactions of the Gulf Coast Association of Geological Societies, v. 41, p. 719-744. Wornardt, W.W., Shaffer, B., and Vail, P.R., 2001, Revision of the Late Miocene, Pliocene, and Pleistocene sequence cycles [abstract ]: American Association of Petroleum Geologists Bulletin, v. 85, p. 1710.

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57 Chapter 3 Late Neogene Paleobathymetry, Relative Sea Level, a nd Basin Margin Subsidence, Northwest San Joaquin Basin, California Abstract The northwestern San Joaquin Basin (SJB) remained n ear sea level throughout the late Neogene despite lying on a tectonically ac tive basin margin. What may be inferred is that from latest Miocene through Late P liocene deposition kept pace with basin subsidence. The late Neogene SJB was 175 km long, 100 km wide, and bounded by mountains to the east, south, and west. It conn ected to the Pacific Ocean at the northwest through a narrow and shallow strait ~13 km wide and <50 m deep. Paleobathymetry determined from benthic foraminifer a faunas from the subsurface of southeastern Lost Hills oil field shows water depth in the SJB >200 m in the latest Miocene, becoming progressively shallower to ~125 m by middle Pliocene, then to ~25 m by middle Late Pliocene where it remained until t he Pacific Ocean connection was tectonically closed at 2.2 Ma. I constructed a rel ative sea level curve for the late Neogene northwest SJB by assigning appropriate wate r depths to the succession of latest Miocene through latest Pliocene molluscan communiti es based on their similarity to published modern communities in San Francisco Bay t hen smoothed it to remove most tectonic “noise.” When compared to the 3rd order Gulf of Mexico eustatic curve, this relative sealevel curve shows very close correlatio n. Using the relative sea level curve to refine stratigraphic timing, I developed a time-thi ckness diagram indicative of relative basin margin subsidence. Latest Miocene basin marg in subsidence averaged ~25 cm/kyr then accelerated to a peak of 140 cm/kyr in the mid dle Early Pliocene coincident with Coast Range uplift. By Late Pliocene subsidence sl owed to 11 cm/kyr then again peaked in latest Pliocene at 86 cm/kyr immediately precedi ng closure of the connection to the Pacific Ocean.Publication Citation : Bowersox, J.R., 2004, Late Neogene Paleobathymet ry, Relative Sea Level, and Basin Margin Subsidence, Northwest S an Joaquin Basin, California: American Association of Petroleum Geologists, Searc h and Discovery Article 30029, www.searchanddiscovery.com/documents/2004/bowersox/ images/bowersox.pdf.

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58 Late Neogene Paleogeography and Paleobathymetry of the San Joaquin Basin By the late Neogene the San Joaquin Basin (SJB) had reached its present overall geographic configuration (Fig. 3.1) and was bounded to the east by the southern Sierra Nevada and to the south and west by the San Emigdio and southern Coast Ranges (see Reid, 1995, fig. 11). Incision of the San Joaquin River began at ~10 Ma (Wakabayashi and Sawyer, 2001) while the base of the Kern River Formation is estimated at 8 Ma (Graham et al, 1988). To the northeast the basin w as filled by fluvial deposits of the late Neogene San Joaquin and Kings Rivers and the substa ntial fan-delta Kern River Formation was deposited by the Kern River on the so utheast basin margin (see Foss, 1972, Pliocene transgressive phase map). This sugg ests that all major southern Sierra Nevada Rivers were draining into the SJB by the lat e Neogene (Fig. 3.1). To the northwest, the SJB opened to the Pacific Ocean thro ugh the shallow and narrow Priest Valley Strait (Loomis, 1990). Uplift of the southe rn Sierra Nevada reached 2.5 km by 57 Ma then stopped until ~ 5 Ma (Wakabayashi and Sawyer 2001). Renewed uplift elevated the southern Sierra Nevada above 3.5 km by 3.0 Ma (Graham et al., 1988). Uplift of the Temblor Range and southern Coast ran ges began their current phase by 5.4 Ma (Miller, 1999). Based on fault-normal convergen ce of the Pacific and Sierran plates across the San Andreas fault transform boundary, Ar gus and Gordon (2001) demonstrated that uplift of the Coast and San Emigd io Ranges probably commenced by 6.6 Ma or 8 Ma. The late Neogene SJB inland sea was 175 km long, 10 0 km wide, and connected to the Pacific Ocean at the northwest through a nar row and shallow strait (Fig. 3.1) ~13 km wide and <50 m deep (Loomis, 1990). Paleobathym etry determined from benthic foraminifera faunas from the subsurface of southeas tern Lost Hills oil field (Fig. 3.2), ~12 km southwest of the basin axis, shows water dept h in the SJB >200 m in the latest Miocene, becoming progressively shallower to ~125 m by middle Pliocene, then to ~25 m by middle Late Pliocene where it remained until t he Pacific Ocean connection was tectonically closed at 2.2 Ma. Abrupt decrease in paleobathymetry at ~4 Ma may be related to rapid sediment deposition in the basin a ssociated with increased uplift of the Coast Ranges (Loomis, 1990) coincident with eustati c sea level fall (Fig. 3.3) and the slowing of subsidence on the basin margin (Fig. 3.4 ) leading to sediment bypass. Northwest San Joaquin Basin Relative Sea Level and Basin Margin Subsidence The thick section of the Etchegoin group exposed on the northwest margin of the SJB has been measured and described in several stud ies (Arnold and Anderson, 1910; Adegoke, 1969; Stanton and Dodd, 1976; Loomis, 1990 ). Approximately 2500 m of late Neogene Santa Margarita through San Joaquin Formati ons strata are exposed from Coalinga to the Kreyenhagen and Kettleman Hills. S edimentary structures and megafossil faunas studied in outcrop over an area s tretching ~130 km from Priest Valley, Fresno County, to the Bacon Hills, Kern County, sug gest that the northwestern SJB remained near sea level throughout the late Neogene despite lying on a tectonically active basin margin. What may be inferred is that from la test Miocene through Late Pliocene deposition kept pace with basin subsidence. To con struct the northwest SJB relative

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59 Figure 3.1. Early Pliocene paleogeography of central Californ ia at ~5 Ma. This figure derives in part from Foss (1972), Harris (1987), an d Loomis (1990). Faults west of the San Andreas fault are not shown. By this time the Sierra Nevada, San Emigdio Range, Temblor Range, and Diablo Range had been uplifted t o near present elevations (Wakabayashi and Sawyer, 2001; Argus and Gordon, 20 01). Location of Purisima Formation and Salinas, Huasna, and Santa Maria Basi ns are shown relative to the SJB at that time. The modern California coastline is show n for reference.

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60 Figure 3.2. Pliocene paleobathymetry of the SJB. Paleobathym etry determined from foraminifera faunas recovered from Bakersfield Ener gy Resources well Tisdale 71X-22, section 22, T27S, R21E, MDB&M, southeast Lost Hills oil field Kern County, California. Subsurface correlations from this stud y. Paleobathymetry is interpreted from foraminifera bathymetry by the Shell Oil Company, S tratigraphic Services (unpublished memorandum dated February 24, 1981). The diatom st ratigraphy is by Mobil Exploration and Producing Services Inc. (unpublishe d memorandum dated September 7, 1983) and is correlated from nearby Bakersfield Ene rgy Resources well Truman 121-26, section 22, T27S, R21E, MDB&M, and from Bowersox (2 003).

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61 Missing SectionHigh Low Northwest San Joaquin Basin Relative Sea Level Fauna Area K e t t l e m a n H i l l s Kreyenhagen H i l l s Non-marine A B C D EC o a l i n g aF LowerU p p e r S a n t a M a r g a r i t a F o r m a t i o n Sequence Cycles Order 3.8 3.7 3.6 3.5 3.4 3.3 3.8.1 3.7.3 3.7.2 3.7.1 3rd4th Gulf of Mexico Eustasy HighLowB C D E A F 1.56 2.09 2.50 2.76 3.21 3.95 4.37 5.73 Ma 2.61-2.68 3.53-3.59 Ma 2.0 5.49 NPD 10 N P D 7 B a N P D 9 N P D 8 N P D 7 B b North Pacific Diatom Zone Figure 3.3. Comparison of the late Neogene northwest SJB rela tive sealevel curve to the Gulf of Mexico eustatic curve (Wornardt and Vail, 1 991; Wornardt et al., 2001). Correlative latest Miocene through Late Pliocene lo wstands are identified by letters A-F. The timing of lowstand events from this figure were used to refine Santa Margarita Formation and Etchegoin group chronostratigraphy to construct Figure 4. The correlative North Pacific diatom zones (Maruyama, 2000; see als o Fig. 3.1) are shown for reference.

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62 L o w e rU p p e r S a n t a M a r g a r i t a F o r m a t i o n 0200 400 600 800 m Stratigraphic Thickness 0 40 80 120 160 Apparent Subsidence Rate (cm/kyr) Figure 3.4. Time-thickness diagram for the Pliocene northwest S JB margin. Individual bars represent ~40 m stratigraphic intervals correla ting to faunazonules 6 and 7 of Adegoke (1969) in the Santa Margarita Formation and ~200 m stratigraphic intervals correlating to faunazonules 8-16 of Adegoke (1969) in the Etchegoin group. Rapid subsidence in the basin coincident with Coast Range uplift in the earliest Pliocene slowed substantially by the middle Pliocene. Late Pliocene basinal subsidence was less than one-third that of the Early Pliocene. Closing of the Priest Valley Strait (Fig. 3.1) in the latest Pliocene coincided with a slight increas e in basin subsidence prior to filling with lacustrine and fluvial sediments of the Tulare Formation.

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63 sealevel curve (Fig. 3.3), appropriate water depths from bathymetry (1.5-25 m) were assigned to the molluscan communities recognized by Stanton and Dodd (1970) in San Francisco Bay and Etchegoin group faunas from the K ettleman Hills. The upper Etchegoin through San Joaquin Formations portion of the northwest SJB relative sealevel curve was constructed by applying the interpreted w ater depths above to the sequence of molluscan communities found in the Kettleman Hills by Stanton and Dodd (1970). This technique was then applied to faunas of the Jacalit os through middle Etchegoin Formations from the Kreyenhagen Hills (Adegoke, 196 9; Loomis, 1990) and Santa Margarita Formation from Coalinga (Adegoke, 1969; C ote, 1991). The curve was then smoothed to remove most tectonic “noise” through th e Jacalitos and Etchegoin Formations and then correlated to the Gulf of Mexic o eustatic curve (Fig. 3.3). Rapid flooding of the SJB during the late Neogene, charac teristic of a relatively shallow silled basin, is suggested by the flat-based highstand sec tions of the relative sealevel curve immediately following lowstands. Using Figure 3 to refine the timing of late Neogene formation boundaries, I was able to construct a tim e-thickness diagram for the northwest SJB and calculate the basin margin subsidence rate (Fig. 3.4). Latest Miocene basin margin subsidence averaged ~25 cm/kyr then acceler ated to a peak of 140 cm/kyr in the middle Early Pliocene coincident with increasing Co ast Range uplift. By Late Pliocene subsidence slowed to 11 cm/kyr then again peaked i n latest Pliocene at 86 cm/kyr immediately preceding closure of the Priest Valley Strait and the connection of the SJB to the Pacific Ocean.DiscussionComparison of basinal paleobathymetry (Fig. 3.2) an d basin margin subsidence (Fig. 3.4) clarifies the basin-filling history. The steady re duction in subsidence at the basin margin during the Early Pliocene beginning ~4.6 Ma and cons istently low rate of subsidence during the Late Pliocene reduced the available acco mmodation space on the basin margin. The abrupt decrease in basinal paleobathym etry at ~4 Ma (Fig. 3.2) corresponds to a fivefold reduction in subsidence rate at the n orthwestern basin margin at the same time (Fig. 3.4). When accommodation space on the w estern basin margin was filled, the additional sediment supply passed on towards the ba sin center. Eustatic lowstands in the Late Pliocene lead to deposition of thick sands out in the basin. With the prograding deltas on the eastern margin included in the overal l depositional picture, sediment supply to the basin was sufficient to fill the SJB to a ve ry shallow depth, to ~25 m at southeastern Lost Hills oil field and probably not much more at the basin center, by latest Pliocene.ReferencesAdegoke, O.S., 1969, Stratigraphy and paleontology of the marine Neogene formations of the Coalinga region, California: University of C alifornia, Publications in Geological Sciences, v. 80, 241 p., 13 pl. Argus, D.F., and Gordon, R.G., 2001, Present tecton ic motion across the Coast Ranges and San Andreas fault system in central California: Geological Society of America Bulletin, v. 113, p. 1580-1592.

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64 Arnold, R., and Anderson, R., 1910, Geology and oil resources of the Coalinga district, Fresno and Kings Counties, California: United State s Geological Survey Bulletin 398, 354 p. Bowersox, J.R., 2003, Pliocene age of the Etchegoi n Group, San Joaquin Basin, California [abstract]: American Association of Petr oleum Geologists, Pacific Section, and Society of Petroleum Engineers, Wester n Region, Conference Program and Abstracts, p. 55. Cote, R.M., 1991, Paleontology of the “Santa Margar ita” Formation on the Coalinga anticline, Fresno County, California [MS thesis]: N orthridge, California, California State University, Northridge, 259 p., 8 pl. Foss, C.D., 1972, A preliminary sketch of the San J oaquin Valley stratigraphic framework, in Rennie, E.W., ed., Guidebook: Geology and Oil Fields of the West Side Central San Joaquin Valley: American Associat ion of Petroleum Geologists, Society of Exploration Geophysicists, and Society of Economic Paleontologists and Mineralogists, Pacific Sections, p. 40-50. Graham, S.A., Carroll, A.R., and Miller, G.E., 1988 ,Kern River Formation as a recorder of uplift and glaciation of the southern Sierra Nev ada, in Graham, S.A., and Olson, H.C., Studies of the Geology of the San Joaq uin Basin: Pacific Section, Society of Economic Paleontologists and Mineralogis ts, Book 60, p. 319-332. Harris, W.M., 1987, Organism interactions and their environmental significance, as exemplified by the Pliocene-Pleistocene fauna of th e Kettleman Hills and Humboldt basin, California [PhD thesis]: College St ation, Texas A&M University, 254 p. Loomis, K.B., 1990, Late Neogene depositional hist ory and paleoenvironments of the west-central San Joaquin Basin, California [PhD the sis]: Stanford, California, Stanford University, 594 p. Maruyama, T., 2000, Middle Miocene to Pleistocene d iatom stratigraphy of Leg 167, in Lyle, M., Koizumi, I., Richter, C., and Moore, T.C. Jr., eds., Proceedings of the Ocean Drilling Program, Scientific Results, v. 167: College Station, Texas, Ocean Drilling Program, p. 63-110. Miller, D.D., 1999, Sequence stratigraphy and contr ols on deposition of the upper Cenozoic Tulare Formation, San Joaquin Valley, Cali fornia [PhD thesis]: Stanford, California, Stanford University, 179 p. Reid, S.A., 1995, Miocene and Pliocene depositional systems of the southern San Joaquin Basin and formation of sandstone reservoirs in the Elk Hills area, California, in Fritsche, E.A., ed., Cenozoic Paleog eography of the Western United States II: Society of Economic Paleontologists an d Mineralogists, Pacific Section, Book 75, p. 131-150. Stanton, R.J., Jr., and Dodd, J.R., 1970, Paleoecol ogic techniques – comparison of faunal and geochemical analyses of Pliocene paleoenvironme nt, Kettleman Hills, California: Journal of Paleontology, v. 44, p. 1092 -1121. Stanton, R.J., and Dodd, 1976, Pliocene biostratigr aphy and depositional environment of the Jacalitos Canyon area, California, in Fritsche, E.A., Ter Best, H., and Wornardt, W.W., eds., The Neogene Symposium: Pacifi c Section, Society of Economic Paleontologists and Mineralogists, p. 85-9 4.

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65 Wakabayashi, J., and Sawyer, T.L., 2001, Stream inc ision, tectonics, uplift, and evolution of topography of the Sierra Nevada, California: Jo urnal of Geology, v.109, p.539-562. Wornardt, W.W., and Vail, P.R., 1991, Revision of t he Plio-Pleistocene cycles and their application to sequence stratigraphy and shelf and slope sediments in the Gulf of Mexico: Transactions of the Gulf Coast Association of Geological Societies, v. 41, p. 719-744. Wornardt, W.W., Shaffer, B., and Vail, P.R., 2001, Revision of the Late Miocene, Pliocene, and Pleistocene sequence cycles [abstract ]: American Association of Petroleum Geologists Bulletin, v. 85, p. 1710.

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66 Chapter 4 Multivariate Community and Environmental Analysis o f Molluscs from the Pliocene Etchegoin Group, Central California Abstract The Pliocene southern San Joaquin Basin (SJB) of c entral California was a shallow marginal ocean basin connected to the Pacif ic Ocean through a long, narrow, and silling shallow seaway. Binary (presence-absence) faunal data from 484 locality collections representing15 stratigraphic intervals of the Pliocene Etchegoin group were analyzed by multivariate statistical methods includ ing ordination by Detrended Correspondence Analysis (DCA), cluster analysis of unweighted pair-group averaging of Euclidean distance of DCA scores, and ordination by Non-Metric Dimensional Scaling to determine environmental gradients controlling the s patial and temporal distributions of mollusc species and species community associations in the SJB. Primary environmental gradients controlling distribution of Etchegoin gro up faunas determined from DCA were found to be substrate, distributed along the DCA ax is 1 (DC1), and paleowater depth, distributed along DCA axis 2 (DC2). Substrate-cont rolled spatial distributions of molluscs were patchy but consistent with modern nea rshore-intertidal communities from comparable substrates. Paleowater depths determine d in this study from DC2 scores range from intertidal to ~25 m at maximum basin floo ding and are shallower than those interpreted for the region in previous studies. Cl uster analysis resolved six bivalve-dominated and one gastropod-dominated commu nities ranked by paleowater depth settings associated with normal marine-adapte d and brackish-tolerant to characteristically brackish communities. Effective temperatures ( sensu Bailey, 1960) determined for the Etchegoin group faunas ranged ~10 -16 C. A cooling trend during lower Etchegoin group deposition (~5.3-4 Ma) was fol lowed by a variable temperature regime through the end of upper Etchegoin group dep osition (~4-2.2 Ma). At eustatic highstands, habitat patchiness was at a minimum whe reas at eustatic lowstand, and late in the history of the Pliocene SJB, a diverse distribu tion of shallow, brackish-water communities developed.Introduction For a variety of geologic reasons, including the po tential of tectonic activity along continental margins and problems inherent in sampli ng existing passive margin sequences (see the discussion in Miller et al., 2003), much o f the reconstruction of the Phanerozoic history of life has, of necessity, been based on th e analysis of strata deposited in

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67 Figure 4.1. Early Pliocene paleogeography of central Californi a at ~5 Ma. Location of the SJB with the approximate extent of the Pliocene marginal ocean basin shaded is noted on the inset map of California. Faults west of the San Andreas are not shown. Location of La Honda and Santa Maria Basins are shown relati ve to the SJB at that time. The modern shoreline and cities locations are shown for reference. Locations of Etchegoin group fossil localities are noted (Table 4.1): A. White Creek Syncline, B. Coalinga Anticline, C. Priest Valley, D. Jacalitos Anticline, E. Kreyenhagen Hills, F. Kettleman Hills, G. Bacon Hills, H. Muddy Creek.

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68 epicontinental seas and marginal ocean basins and s eas. One of the inherent questions associated with such an analysis is not only how th e biotic elements may have differed between epicontinental settings and more open-marin e shelfal environments, but also how various environmental controls may have differe d as well. The Pliocene record of the San Joaquin Basin (SJB), central California, of fers an opportunity to not only compare the biotic feedbacks of distribution and st ructure of essentially modern faunas from a marginal sea under a wide range of environme ntal settings differing from the nearby ocean, but also serve as a model for the imp act of the current phase of global climate change on faunas in modern shallow-coastal and ocean-marginal environments. However, whereas the Etchegoin group (informal SJB nomenclature) includes the Pliocene record of a biotic history substantially d ifferent than that of nearby open-marine, coastal waters, was this history so different from that of coastal waters that environmental controls on molluscan community distribution and st ructure were markedly different? The Pliocene southern SJB was a shallow marginal oc ean basin (Fig. 4.1) subject to environmental variability driven by eustatic sea -level change, intermittent regional tectonic interruption of the connection to the Paci fic Ocean, and paleoclimatic variation. Previous studies demonstrate paleoenvironmental int erpretations for the Etchegoin group molluscan faunas subjectively correlated by uniform itarian analogy to modern environments (Stanton and Dodd, 1970; Dodd and Stan ton, 1975; Loomis, 1990). However, as effectively as this method may be appli ed in paleocommunity studies, the very nature of subjective uniformitarian analogy wi ll generalize the controls inferred as affecting community structure and distribution and thus generalize the overall paleoenvironmental interpretation for the basin. T hus these previous paleoenvironmental interpretations are generally consistent with moder n California estuarine settings. This study resolves temporal and spatial environmental c ontrols of substrate and paleowater depth on the composition and distribution of nearsh ore marine mollusc communities of the Pliocene SJB through the application of multiva riate statistical analysis. Spatial heterogeneity of habitats are demonstrated by varia tions in molluscan communities and their distributions as proxies for environmental co ntrols. Critical environmental changes occurred in the SJB during deposition of the Etchegoin group (Fig. 4.2-4.3): 1.) the upper Jacal itos Formation records a short-term 4thorder eustatic fall with consequent extinction and reorganization of the SJB fauna; 2.) the uppermost Etchegoin Formation depicts rapid environ mental deterioration leading to the regional extinction of molluscs in the SJB at ~4 Ma; and 3.) the upper San Joaquin Formation displays favorable marine conditions begi nning with rapid basin flooding at ~3.1 Ma deteriorating to brackish conditions and the extinction of all marine taxa with the closure of the Priest Valley Strait at ~2.2 Ma. In general, early descriptive paleontologic and paleoclimate studies of the of the SJB (Arnold, 1909; Arnold and Anderson, 1910; Smith, 1919; Woodring et al., 1940) discussed the c auses of extinction in the Pliocene SJB simply in terms of climatic cooling or increasi ngly brackish conditions through time. Adegoke (1969) was the first to address the overall paleoecologic implications of the SJB’s partial isolation during the Pliocene in term s of changes in paleosalinity, nutrient supply, as well as paleoclimate and favored increas ingly brackish conditions as the

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69 Figure 4.2. Composite stratigraphic section of the Etchegoin group and Pliocene northwest SJB 4th-order relative sea level curve. The division of the San Joaquin Formation into informal lower and upper members at the base of the upper San Joaquin Formation Pecten zone was first used by Woodring et al. (1940) and has been followed in this paper. Subdivisions of the upper Etchegoin-up per San Joaquin section from 12002500 m stratigraphic levels are generalized from Wo odring et al. (1940).

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70 Figure 4.3. Comparison of molluscan faunal diversity with gen eralized relative sealevel, paleotemperature and paleosalinity (revised from Bowersox, 2005). Diversity is given as total species (species richness, S) found in average ~200 m stratigraphic intervals in the Jacalitos and Etchegoin Formation and by fau na zone of Woodring et al. (1940) in the San Joaquin Formation. Correlations of biostra tigraphic fauna zonules 6-16 of Adegoke (1969) are noted. Temperature curve (solid line, generalized effective temperature from this study) and indicated paleosal inity (dotted line) are shown for reference. Low S corresponds to periods of lower t emperature and brackish conditions suggesting faunal response to marginal environments by slowed immigration and concomitant exclusion of species adapted to normal marine conditions. Fauna zones of Woodring et al. (1940; Fig. 4.2) are noted for corr elation reference by circled lower-case letters a-g: a upper Etchegoin Formation Patinopecten through 2nd Mya zones; bbasal San Joaquin Formation, Cascajo Conglomerate; c lo wer San Joaquin Formation, Neverita zone; d upper San Joaquin Formation, Pecten zone; e upper San Joaquin Formation, Trachycardium zone; f upper San Joaquin Formation, Acila zone; uppermost San Joaquin Formation, upper Mya zone. Extinction events are noted at major divers ity declines as circled uppercase letters A-H.

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71 driving force responsible for diversity decreases a nd extinction. Subsequent to Adegoke (1969), the paleoecology of the Pliocene SJB was ad dressed by Stanton and Dodd (1970, 1972, 1997), Dodd and Stanton (1975), and Loomis (1 990). In their landmark paleoecology papers, Stanton and Dodd (1970) and Dodd and Stanton (1975) demonstrated the relationship betwee n paleosalinities and the sedimentary cycles of the upper Etchegoin Formation and upper S an Joaquin Formation of the Kettleman Hills. These strata record four major tr ansgressive cycles during which marine waters flooded the SJB prior to the closing of the connection to the Pacific Ocean (Stanton and Dodd, 1970; Fig. 4.2-4.3). Stanton an d Dodd (1970) and Dodd and Stanton (1975) used the physical and biotic characteristics of San Francisco Bay, California as an analog for the Pliocene San Joaquin Basin. Seven m odern molluscan community biofacies were identified through Q-mode cluster an alysis by unweighted pair-group averaging (UPGMA) using both the Jaccard distance c oefficient (Stanton and Dodd, 1970) and a distance coefficient empirically-derive d from five levels of estimated relative abundance data (Dodd and Stanton, 1975). These sev en biofacies range from normal-marine conditions in their outer bay biofaci es to brackish-water inner bay biofacies in the upper reaches of San Pablo Bay (St anton and Dodd, 1970). In their subsequent analysis of the Pecten and upper Mya zones of Woodring et al. (1940) in the Kettleman Hills, Dodd and Stanton (1975) refined th eir biofacies model erecting eight communities interpreted as occurring in normal-mari ne, outer-bay through brackish-water, inner-bay and freshwater environmen ts. However, the multivariate statistical methods available to Stanton and Dodd ( 1970, 1972) and Dodd and Stanton (1975) did not allow quantitative evaluation of the environmental parameters that controlled the spatial and temporal distributions o f their biofacies communities, and this present study endeavors to investigate these contro ls. Loomis (1990) interpreted Etchegoin group molluscan paleoecology and paleoenvironments from the Kreyenhagen Hills and Ke ttleman Hills through the application of uniformitarian analogy to extant tax a within those units. These interpretations were summarized in their stratigrap hic context by environmental setting (i.e., unprotected shoreline, protected shoreline, bay/estuary), water depth from intertidal to greater than 100 m, and substrate ranging from m ud to gravel and rocks (Loomis, 1990). Examples of paleoenvironmental interpretati ons were given for faunas from localities in the upper Jacalitos, Etchegoin, and m iddle San Joaquin formations in the Kreyenhagen Hills outlining the methodology employe d. Loomis (1990) concluded that the Etchegoin group fauna is composed primarily of taxa characteristic of modern bay and estuarine environments many of which were interpret ed to have lived in tidal flats. Faunas from four localities in the Etchegoin sugges tive of brackish water are consistent with an estuarine paleoenvironmental interpretation (Loomis, 1990), whereas those interpreted as representing open shorelines occurre d in sedimentary facies consistent with high-energy, near-shore environments (Loomis, 1990) However Loomis (1990) overestimated paleobathymetry of the northwestern m argin, a region that remained at or near sea level throughout the Pliocene (Stanton and Dodd, 1976), by assuming water depths based on the maximum a particular fauna coul d have occupied. Other than this

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72 issue of paleobathymetry, in an overall sense the p aleoecological and paleoenvironmental interpretations for the Kreyenhagen Hills (Loomis, 1990) are consistent with those of the nearby Kettleman Hills (Stanton and Dodd, 1970, 197 2, 1997; Dodd and Stanton, 1975). Geologic Setting and Paleogeography On the northwest margin of the SJB, the Etchegoin g roup consists of a thick succession of non-marine to shallow-marine facies t otaling 2430 m in a composite section that has been measured and described in many studie s (Arnold and Anderson, 1910; Woodring et al., 1940; Adegoke, 1969; Stanton and D odd, 1972; Loomis, 1990; Hall and Loomis, 1992): the Jacalitos Formation (635 m thick as adapted from Hall and Loomis, 1992; Fig. 4.2, ~5.3-4.8 Ma), Etchegoin Formation (1 060 m thick as adapted from Hall and Loomis, 1992; Fig. 4.2, ~4.8-4.0 Ma) which inclu des the uppermost Etchegoin Formation exposed in the Kettleman Hills (~200 m thi ck, Woodring et al., 1940), lower San Joaquin Formation (400 m thick as adapted from Woodring et al., 1940; Fig. 4.2, 4.0-3.1 Ma) and upper San Joaquin Formation (335 m thick as adapted from Woodring et al., 1940; Fig. 4.2, 3.1-2.2 Ma). The Pliocene SJB was a shallow, marginal ocean basi n 175 km long, 100 km wide (Fig. 4.1) ringed by estuaries, tidal marshes, and tidal deltas (Loomis, 1988, 1990; Reid, 1995) and connected to the Pacific Ocean on the nor thwestern margin by the ~30 km long and ~13 km wide Priest Valley Strait (Loomis, 1990; Powell, 1998; Fig. 4.1). Shallow-water macrofauna collected from the Etchego in group in the Priest Valley Strait (Arnold, 1909; Arnold and Anderson, 1910; Nomland, 1917; Rose and Colburn, 1963; Merrill, 1986; Bowersox, 2005) suggest a depth at m aximum transgression of ~15 m and thus this feature acted as a sill during the Plioce ne. While the northwest SJB margin remained at or near sea level throughout the Plioce ne (Stanton and Dodd, 1976), the subsurface stratigraphic record from the deepest pa rt of the basin, about 75 km southeast of the study area, shows continual decrease in pale obathymetry through the Pliocene with a short period of rapid shallowing between the Etch egoin and San Joaquin formations (Bowersox, 2004).Methodology To develop a temporal diversity model for the Plioc ene San Joaquin Basin mollusc, presence-absence data was compiled from 42 5 localities with verified stratigraphic positions from the past century of li terature (Arnold, 1909; Arnold and Anderson, 1910; Hoots, 1930; Woodring et al., 1940; Adegoke, 1969; Loomis, 1990) and new collections from 59 localities in Etchegoin group outcrops located in the foothills of the western and southern margins of th e San Joaquin Basin during 1999-2004 (Table 4.1). Temporal resolution in the form of a near-uniform vertical stratigraphic distribution of the 484 locality collections, i.e., gaps less than ~30 m between stratigraphically successive locality collections, is best in the basal Jacalitos, uppermost Etchegoin, and upper San Joaquin formations (Fig. 4 .4). The 59 new collections demonstrate that the Etchegoin group fauna lived in shallow-water, low-depositional gradient foreshore, tidal-flat, and tidal-channel e nvironments. Specimens showed little

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73 Table 4.1. Areal and stratigraphic distributions and numbers of locality collections compiled in this study. Locations of Etchegoin gro up fossil localities (columns) are noted on Figure 4.1: A. White Creek Syncline, B. Coalinga Anticline, C. Priest Valley, D. Jacalitos Anticline, E. Kreyenhagen Hills, F. Kettleman Hills, G. Bacon Hills, H. Muddy Creek.

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74 Figure 4.4. Species richness and occurrences in locality coll ections. Species richness and occurrences from 484 locality collections were compiled in 116 ten-meter sample intervals. The number of locality collections compr ising 10 m sample intervals shoes sampling to have been heaviest in the uppermost Etc hegoin (~1500-1700 m) and basal upper San Joaquin (~2100-2300 m) where the Etchegoin group is best exposed (Table 4.1). This figure demonstrates the relationship be tween species richness and abundance (Table 4.2A): species are most abundant where there are many species present. While the number occurrences correlates well to the number of localities in a sample interval ( r2 = 0.82) species richness only weakly relates to sampl ing intensity (r2 = 0.58) suggesting that it is unlikely that abundant taxa are over represen ted in the locality collections. SJB extinction events are noted A-H (adapted from Bower sox, 2005; Chapter 6).

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75 evidence of abrasion, fragmentation, or bioerosion suggesting minimal transport, reworking, and exposure on the sea floor and rapid burial resulting in a largely parautochthonous assemblage ( sensu Kidwell et al., 1986). Minor taphonomic displacement of faunal elements was apparent in loc ality outcrops and in bulk samples during processing in the form of bathymetrically di splaced taxa or faunal elements displaced from adjacent habitats. Preservation was excellent for calcitic taxa (oysters, pectinids, mussels, and some gastropods), but gener ally poor for aragonitic taxa with most shells showing effects of leaching. Collectio ns from several localities consisted entirely of molds of aragonitic taxa. It could be argued that the composition of locality collections may be biased due to differential prese rvation of thick-shelled taxa versus thin-shelled taxa, however Behrensmeyer et al. (200 5) found that taphonomic effects are neutral with respect to durability. Differences in the correlation of the base of the E tchegoin group in previous studies were mitigated by correlating the relative stratigraphic positions of all fossil localities in this study to a composite stratigraph ic column constructed for the central Kreyenhagen Hills where the complete Etchegoin grou p section is exposed. The composition of each locality collection was reviewe d and updated to the current accepted taxonomy to remove synonymous species and uncertain identifications (sp., aff., ident., and “?”) as well as reworked taxa in preparation fo r statistical analysis. The manner of these revisions was uniformly applied to all faunas in this study. The Etchegoin group mollusc fauna consists of 176 species and subspecie s including 101 bivalve and 75 gastropod species and subspecies. Approximately 35 % of the Etchegoin group mollusc fauna consists of extant species and all are repres entative of shallow-water, nearshore environments (Bowersox, 2005). A subset of data fr om each sample interval was compiled for species endemic to the SJB, herein def ined as those extinct species without a recorded presence outside of the SJB, for the cal culation of diversity indices. Endemic species comprise ~29% of the fauna (30 bivalve speci es and 23 gastropod species) although some of the appearance of endemism in the San Joaquin Basin fauna may be an artifact of an incomplete California Pliocene fossi l record (Bowersox, 2005). In toto these faunas (Arnold, 1909; Arnold and Anderson, 19 10; Hoots, 1930; Woodring et al., 1940; Adegoke, 1969; Loomis, 1990; this study) form a stratigraphically constrained database that includes the entire Etchegoin group f auna. Statistical Analysis The basis for the statistical analysis in this stud y are two pieces of information determined from locality collections: the number of species present in a locality collection (species richness, S), and the number of locality c ollections in a sample interval where a given species was found (occurrences, N). Small-sc ale population indices, S and N were compiled from locality collections (n) in 116 ten-m eter stratigraphic sample intervals (Fig. 4.4). S and N are cross-correlated (r2 = 0.86) allowing the use of occurrences as a proxy for abundance because an ecological group wit h more occurrences is likely to have been locally more abundant, had a greater geographi c distribution, as well as a broader environmental range(Hayek and Buzas, 1997; Buzas an d Culver, 1999; Madin et al.,

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76 Figure 4.5. Sampling intensity and covariance of S and N. S and N are cross-correlated (r2 = 0.86) which allows the use of occurrences from t he compiled binary (presenceabsence) database as a proxy for abundance: an ecol ogical group with more occurrences is likely to have been locally more abundant, had a greater geographic distribution, and broader environmental range (Madin et al., 2006).

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77 Figure 4.6A. Distribution of species richness of the total and endemic Etchegoin group faunas. Distribution of species richness and speci es occurrences were tested for sampling bias of the faunal composition. Species richness of both the total and endemic Etchegoin group faunas demonstrate a log-normal distribution which is characteristic of natural populations as sampling intensity increases (Hayek and Buzas, 1997).

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78 Figure 4.6B. Rank order occurrences of species comprising the total and endemic faunas. Likewise the rank order occurrences of spe cies comprising the total and endemic faunas also follow the log-normal distribution. Th ese figures also suggest that increasing sampling intensity beyond the 484 localities of thi s study would at best add a few very rare species, if any, to the fauna. Therefore the Etchegoin group mollusc fauna has been appropriately and adequately sampled.

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79 2006; Fig. 4.5). Distribution of species richness and species occurrences are presented in Figure 4.6A-B. Sampling was heaviest in the uppermost Etchegoin (~1 500-1700 m) and basal upper San Joaquin (~2100-2300 m) where the Etchegoin group is best exposed (Fig. 4.4, Table 4.1). In order to test for bias due to great er sampling intensity of better exposed sections the Etchegoin group fauna was modeled afte r the technique of Crampton et al. (2003). Outcrop areas were determined for nine str atigraphic intervals within the marine section of the Etchegoin group exposed in the Coali nga region corresponding to the fauna zonules of Adegoke (1969), the smallest practical s cale for this test, from the geologic maps of Woodring et al. (1940), Adegoke (1969), Dib blee (1971), Hall and Loomis (1992), and field work of this study. The outcrop area of the Etchegoin group marine section in the Coalinga region totals ~340 km2 and ranges from a low of ~3 km2 of exposed and preserved basal Jacalitos (zonule 8 of Adegoke, 1969) on the Coalinga Anticline to a high totaling ~80 km2 of uppermost Etchegoin (zonule 12 of Adegoke, 1969; Patinopecten through Littorina zones and their correlates of Woodring et al., 194 0) exposed in the Kettleman Hills North, Middle, and S outh Domes (Fig. 4.7). Spearman's correlation coefficient matrix was calculated using the module in PAST software version 1.45 (PAlaeontological STatistics; Hammer et al., 2 001) for the outcrop area (A) of each of the nine stratigraphic intervals and the number of locality collections (n), S, and N from each interval (Table 4.2A). Contrary to the r esults of Crampton et al. (2003) no statistically significant correlation exists betwee n A and any of the three tested factors (p > 0.05) suggesting that the nature of the collecti ons of the Etchegoin group in toto have not introduced a bias when the data for species ric hness and other paleoecologic components are compiled. A second Spearman's correlation coefficient matrix was calculated for n, S, and N from the116 ten-meter stratigraphic sample (Table 4 .2B). Not unexpectedly, correlation exists between n, S, and N (p < 0.05). However cor relation does not demonstrate causation. N is largely explained by n (r2 = 0.82; more collections yields more occurrences of taxa). S is weakly related to n (r2 = 0.58) suggesting that abundant taxa are not overly represented in the locality collecti ons. This relationship is much like that discussed by Poore and Rainer (1974) in which they concluded that differences in regional diversity are not related to sample size. The corollary to over-represented abundant taxa is the under representation of middle -rank and rare taxa. The rank abundance of species in a natural population is a l og-normal relationship (Buzas et al., 1982; Hayek and Buzas, 1997; Buzas and Culver, 1999 ). To test for under-representation species in the Etchegoin group fauna the rank occu rrences of the species from the 15 stratigraphic intervals deposited during the 4th-or der eustatic cycles was determined (Fig. 4.2, 4.8A-D). The rank occurrences of species in t he lower Jacalitos fauna (Fig. 4.8A) is indicative of under-represented middle-rank and rar e species which suggests any conclusions that may be drawn from th that portion of the fauna should be considered tentative.. Five other faunas (upper Jacalitos, up per Etchegoin A as well as the Littorina Trachycardium and Acila zones; Fig. 4.8A-B, D) are demonstrative of the un derrepresentation of rare species although the presenc e or absence of only rare taxa does not

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80 Figure 4.7. Outcrop area of marine Etchegoin group stratigrap hic intervals corresponding to the fauna zonule of Adegoke (1969) and the number of localities per interval. The test for bias due to greater samplin g intensity of better exposed sections the Etchegoin group fauna was modeled after Crampton et al. (2003) where outcrop area of stratigraphic intervals (A) are tested against the number of locality samples from each of the intervals (n). The total outcrop area of the Etchegoin group i n the Coalinga region is ~340 km2 and ranges from ~3 km2 of exposed and preserved basal Jacalitos (zonule 8 of Adegoke, 1969) on the Coalinga Anticline to a high totaling ~80 km2 of uppermost Etchegoin (zonule 12 of Adegoke, 1969; Patinopecten through Littorina zones and their correlates of Woodring et al., 1940) exposed in the Kettleman Hills North, Middle, and South Domes (Fig. 4.1). Spearman's correlation coe fficient matrix was calculated from the data from each stratigraphic interval using the module in PAST software version 1.45 comparing A, n, S, and N from each interval (Table 4.2A). Contra ry to the results of Crampton et al. (2003) correlation cannot be proved between A and any of the three tested factors (p > 0.05) suggesting that the Etch egoin group in toto has been appropriately collected.

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81 Table 4.2A. Test of correlation between outcrop area and the number of localities, species richness, and number of occurrences. Corre lation was tested between the outcrop area (A) of each of the nine stratigraphic interval s and the number of locality collections (n), S, and N from each interval. Correlation coef ficients are given below the diagonal whereas the probabilities that the quantities being compared are not correlated are given above the diagonal. Contrary to the results of Cra mpton et al. (2003) correlation cannot be proved between A and any of the three tested fac tors (p >0.05) suggesting that the Etchegoin group in toto has been appropriately collected. Table 4.2B. Test of correlation between the number of localit ies, species richness, and number of occurrences. Correlation was tested for n, S, and N from the116 ten-meter stratigraphic sample. Not unexpectedly, correlatio n is proved between n, S, and N (p <0.05). N is largely explained by n (r2 = 0.82; more collections yields more occurrences of taxa) therefore suggesting that all taxa are app roximately uniformly sampled at all sampling intensities. S is weakly related to n (r2 = 0.58) suggesting that abundant taxa are not overly represented in the locality collections.

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82 Figure 4.8. Test for under-represented species in the Etchego in group fauna. Underrepresentation of species in the Etchegoin group fa una was tested by ranking the occurrences the species from the 15 stratigraphic i ntervals deposited during the 4th-order eustatic cycles (Fig. 4.2). The rank abundance of species in the lower Jacalitos fauna (A) is indicative of under-represented middle-rank and rare species which mitigates any conclusions that may be drawn from statistical anal ysis of the fauna. Five faunas (upper Jacalitos, upper Etchegoin A, Littorina zone, Trachycardium zone, and Acila zone; A-B, D) are demonstrative of the under-representation of rare species although the presence or absence of rare taxa does not have a significant ef fect on diversity analysis (Marchant, 1999). Faunas from the balance of the intervals ha ve been adequately sampled.

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83 have a significant effect on analysis of diversity (Marchant, 1999). Multivariate Statistical Analysis Multivariate analysis was performed using the modul es in PAST software version 1.44 (PAlaeontological STatistics; Hammer et al., 2 001). Questions of community composition and environmental gradients explaining the spatial distribution and temporal variations of communities determined the methods an d exploratory metrics appropriate to this study as outlined in the recommendations of Sh i (1993). Faunal composition of each locality collection was analyzed with multivariate exploratory metrics by stratigraphic interval corresponding to 4th-order eustatic cycles (Fig. 4.2) in the following three steps: 1.) Detrended Correspondence Analysis ordination (D CA; discussed in Peet et al., 1988) to delineate the environmental gradients that deter mined distribution of the organisms; 2.) Q-mode cluster analysis (discussed in Dodd and Stan ton, 1975) of DCA coordinates using UPGMA of the Euclidean distance coefficient t o identify community associations; and 3.) ordination (Shi, 1993; Pillar, 1999) by Non -Metric Dimensional Scaling (NMDS) to cross-check the congruency and rigor of the clus tering in identifying cluster-group community associations. These three metrics reduce the within-sample variability to environmentally interpretable coordinates in two-di mensional space. The DCA module of PAST uses the same algorithm as DECORANA (Hill a nd Gauch, 1980) incorporating the modifications of Oksanen and Minchin (1997; Ham mer et al., 2006). The DCA output of PAST includes eigenvalues for axes 1-4, c alculated coordinates for axes 1-3, and graphical presentations for axes 1-2 and 2-3. A default of 26 segments is used for detrending in PAST version 1.44 although the number of segments may be varied between 10 and 46. However, for any data set in th is study only minor differences in eigenvalues (< 0.01 for axis 2; < 0.05 for axes 3 and 4) were observed over the range of 10-46 detrending segments. NMDS of DCA axes 1-2 coordinates used the Euclidean distance coefficient with trials repeated to achiev e the lowest Shepard Plot stress value. Shepard Plot stress values <0.06 for the 15 interva ls in this study indicate the clusters were nearly perfectly resolved. Where to partition cluster analysis can be problematic (Romesburg, 1984). Traditionally, this has been ac complished using one of two approaches: either by a fuzzy partitioning into com munity associations by inspection (e.g. Pillar, 1999) or by a partitioning where there is t he greatest range in the similarity between dendrogram branches (Romesburg, 1984). Pil lar (1999) offered a third method of an iterative algorithm of bootstrap resampling; the results of this method, however, did not improve upon previously published fuzzy partiti oning (Pillar, 1999). In this study, fuzzy partitioning and partitioning where the simil arity range was greatest were compared, and it was determined that partitioning b y the greatest similarity range could not be reliably resolved by NMDS whereas NMDS did r esolve fuzzy partitions. The abundance data set from 59 localities of this s tudy were initially treated as a single sample for comparisons of metrics calculated from abundance and presence-absence data. This initial comparison sup ported Marchant’s (1990) observation that DCA ordinations based on presence or absence o f species were not substantially different than those based on abundances. The pres ence-absence data set of 484 locality

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84 collections was divided for multivariate analysis i nto 15 stratigraphic sample intervals corresponding to the SJB 4th-order eustatic cycles each consisting of from 12 t o 81 locality collections (Fig. 4.2, Table 4.1). The sm allest and largest number of locality collections comprising a sample interval were from the upper Jacalitos and the Siphonalia zone of Woodring et al. (1940) in the uppermost Etc hegoin, respectively. Temporal resolution in the form of a uniform vertical strati graphic distribution of locality collections within a sample interval is best in the basal Jacalitos, uppermost Etchegoin, and upper San Joaquin formations (Fig. 4.7). Spati al resolution within these sample intervals was most refined where many locality coll ections were geographically widely distributed and fell within a small stratigraphic i nterval. Effective Temperature The methods of Bailey (1960) as refined by Hall (19 64, 2002) were adopted in this study to determine the nearshore water tempera tures in the SJB during Etchegoin group deposition. The duration of annual warmth re presented by a taxon is determined from the mean sea surface temperatures (SST) plotte d by latitude of its geographic range (see the example in Hall, 1964, fig. 2). Mean effe ctive temperature (ET, C; Bailey, 1960; discussed in Hall, 1964, 2002; Axelrod and Ba iley, 1969; Loomis, 1990) weights the temperatures of the warmest months and coolest months represented by the latitudinal ranges of the taxa comprising a fauna to arrive at a single mean annual temperature representative of the entire fauna. In this study, ET of each locality was calculated from the preferred effective temperature of the extant s pecies and genera present in the locality collection from the data presented in Hall (2002, A ppendix A10-A12). Mean ET for each locality collection was calculated from the mean te mperatures of the warmest months (WM, C) and coldest months (CM, C) represented by each species in the locality collection as: ET = (18 WM 10 CM) / (WM CM +8)(1) (Bailey, 1960). ET along the modern California coa st is 15.4 C at 33 N latitude and 15.2 C at 34 N latitude (Loomis, 1990). For each of the 15 stratigraphic intervals a weighted mean effective temperature (ET*) was calcu lated by weighting each taxon’s ET relative to its number of occurrences in the given stratigraphic interval as: (2) where ETi is ET and Ni is N of the ith species in the stratigraphic interval and n is the total number of species occurring in the stratigraphic in terval. Where a single taxon was present in a locality collection, ET* was assigned to that locality rather than bias the interpretation of the stratigraphic interval by ove rstating the contribution of single taxon

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85 occurrences. In order to better understand tempora l trends in ET in the Pliocene SJB and its effect on community composition and distributio n, in contrast to the approach of Hall (2002) faunas from locality collections or stratigr aphic intervals were not assigned to generalized paleoclimatic regions. Mean ET for 10 m sample intervals is presented in Figure 4.9.Results The multivariate metrics employed in this study eff ectively describe the environmental variables controlling the distributio n and mollusc communities in the Pliocene SJB and delineate their composition. By comparing environmental preferences of the extant taxa in the Etchegoin group fauna fou nd in the locality collections to plots of DCA scores, DCA axis 1 (DC1) distributes locality c ollections along a gradient of substrate texture identified from the substrate pre ferences of extant taxa found in those collections, from relatively coarser to relatively finer grain substrates. Depending on the stratigraphic interval, substrates interpreted from DC1 range from hard bottoms to mud with the preponderance of locality collections iden tified as representative of muddy-sand to sand as exemplified in Figure 4.10A-C. This int erpretation is consistent with the sediment enclosing the fossils, sediment source are a (Loomis, 1990), and indicative of taphonomic displacement of rockyand mud-bottom ta xa from adjacent or habitats not preserved or exposed in the study area. DCA axis 2 (DC2) distributes locality collections inversely along an environmental gradient of increa sing water depth. Review and analysis of DCA axis 3 proved it to be a folded and distorted variant of DC1 and as a consequence was not used in this analysis (see also the discussion in Scarponi and Kowalewski, 2004). Although the absolute ranges of axes differed between sample intervals the relationships of the substrate and wa ter-depth environmental gradients were similar overall. Plots of DCA axis scores are in t wo forms: one where substrate and water depth environmental gradients influenced the distributions of locality collections approximately equally along DC1 and DC2 (Fig. 4.10A C), and one form where locality collections were very strongly distributed along th e DC2 water depth environmental gradient with only a few locality collections being distributed along the DC1 substrate gradient (Fig. 4.10B). Distribution along the DC1 substrate gradient in st ratigraphic intervals where all Fuzzy partitioning of dendrograms (Fig. 4.11A-4.11B ) delineated faunal and environmentally-related locality collections sugges ted by DCA. Ordination by NMDS (Fig. 4.12A-B) to confirm the appropriateness of fu zzy dendrogram partitioning provided mixed results in the two examples presented here. Whereas the Siphonalia zone clusters are confirmed by NMDS (Fig. 4.12A), Pecten zone clusters 1, 2, and 5 are not as well resolved (Fig. 4.12B) suggesting that clusters 2 an d 5 represent sub-communities of cluster 1. Because ~65% of the Etchegoin group faun a is comprised of extinct species it was necessary to reduce the species lists of the lo cality collections of each cluster partition to their component genera and thus genera lize ecological constraints on distributions. Molluscan communities were resolved by compiling occurrences of genera by summing the occurrences of each genus within a c luster partition. The compilations of

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86 Figure 4.9. Effective temperature averaged in 10 m stratigrap hic intervals. The Early Pliocene through early upper Etchegoin deposition w as a period of warm, equitable climate. Cooling at the end of Etchegoin depositio n was followed by the variable climate with temperature peaking at ~16 C during deposition of the lower San Joaquin then declining in concert with Northern Hemisphere cooli ng to a low of ~10 C shortly before the end of upper San Joaquin deposition.

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87 Figure 4.10A. Substrate and water depths from Siphonalia zone DCA. DCA of two sample intervals within the Etchegoin group shows t he contrast of locality collections distributions along environmental gradients. DC1 di stributes locality collections from hard or rocky to mud substrates and DC2 distributes localities from deeper water depths to intertidal. In the uppermost Etchegoin Siphonalia zone locality collections are distributed approximately equally along both substr ate and water depth gradients. Cluster groups 1-6 were identified by Q-mode cluster analys is (discussed in Dodd and Stanton, 1975) of DC1 and DC2 coordinates UPGMA of the Eucli dean distance coefficient to identify faunal associations (Fig. 4.11A) confirmed by NMDS (Fig. 4.12A). At the extremes of DC1 the species of cluster group 3 are characteristic of rocky substrates while cluster group 5 is characteristic of a mud substrat e. Locality collections labeled A-H were used to determine the water paleodepth relationship to DC2 scores.

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88 Figure 4.10B. Substrate and water depths from Pecten zone DCA. In the upper San Joaquin Pecten zone the substrate distribution along DC1 is eithe r muddy-sand at a score of zero or mud at a score of one. Thus distributio n of locality collections is strongly controlled by paleowater depth along DC2. Faunal a ssociations determined by cluster analysis and NMDS (Fig. 4.11B, 4.12B) are labeled 1 -5.

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89 Figure 4.10C. Substrate preferences of the frequently occurring species from Siphonalia zone DCA clusters. Ecological preferences of taxa are from Grau (1959) Keen (1963, 1971), Morris (1966), MacNeil (1967), Waller (1969) Golikov and Scarlato (1970), Morris et al. (1980), Rehder (1981), Smithy (1991), Coan et al. (2000), Kulikova and Sergeenko (2003), Minchin (2003), Tkachenko (2003), Lam and Morton (2004), and Sasaki. et al. (2004).

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90 genera were then sorted to determine the rank order of the genera in each cluster partition. Cluster partitions with similar rank orders of the most prevalent genera, those comprising ~67% of the occurrences, were combined into a single community association. Six bivalve-dominated and one gastropod-dominated mollu scan communities, named for the dominant genera comprising the faunas, were determi ned in this study through multivariate analysis: 1. PatinopectenChione 2. Patinopecten-Macoma 3. MacomaCryptomya 4. Mya-Macoma 5. Mytilus-Ostrea 6. Littorina, and 7. MyaAnadara Gastropods are minor components, both in terms of a bundance and diversity, of these bivalve-dominated communities. The Patinopecten-Chione and PatinopectenMacoma communities are generally characteristic of sandy s ubstrates but include faunas broadly characteristic of mud-sand substrates. Macoma-Cryptomya, Mya-Macoma, and MyaAnadara communities are characteristic of faunas from san dy-mud to mud substrates, whereas the Mytilus-Ostrea and Littorina communities are characteristic of faunas living on hard to rocky substrates. Locality collections from eight sample intervals sh owed strong distribution control along DC2 consistent with paleo-water depth These include the lower Jacalitos, lower Etchegoin, upper Etchegoin A, Macoma zone, Pseudocardium zone, Cascajo Conglomerate, Neverita zone, and Pecten zone intervals. Paleowater depths inhabited by fossil faunas from Quaternary deposits of the Po Pl ain, Italy, were successfully derived from DC1 scores by Scarponi and Kowalewski (2004) t hrough statistical correlation of modern weighted-mean bathymetric range of genera co mprising the fauna. In contrast to their method, in this study paleo-water depth was d etermined by correlation of DC2 scores of each locality collection with the occurre nces of bathymetrically restricted extant species present in the Etchegoin group fauna or gen eral bathymetric ranges for genera where the species are extinct assuming that habitat preferences for these taxa have not changed since the Pliocene (Fig. 4.13A). The depth ranges for the bathymetrically restricted taxa in each sample interval were plotte d versus the DC2 score of the locality collection where they were present and a trend line established (e.g., Fig. 4.13B). The specific relationship between DC2 score and paleowa ter depth varied between sample intervals due to the variations faunal compositions between 4th-order eustatic cycles (Stanton and Dodd, 1997; Bowersox, 2005) and a sing le relationship could not be applied but one or two locality collections have a zero sco re resolves as dominantly sandy substrate with the offset cluster with a score of o ne resolved as a mud substrate. In the four sample intervals where a single locality is di splaced along DC1 from the dominant locality clusters (lower Jacalitos, lower Etchegoin upper Etchegoin below the Patinopecten zone, and Macoma zone), these locality collections are monospecific (see the example in Fig. 4.10B). The three sample inter vals where the offset cluster includes two localities ( Pseudocardium zone, Cascajo Conglomerate, and Neverita zone), the offset clustered faunas include three to six taxa. uniformly to all sample intervals as a consequence. Water depths for the balance of the l ocality collections in a sample interval were calculated from the DC2 scores according to th e relationship established by correlation within their respective stratigraphic i ntervals. Except for the Pecten zone fauna where the shallowest water depth determined f rom DC2 was ~1 m, highest DC2

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91 Figure 4.11A. Dendrogram from the upper Etchegoin Siphonalia zone. Dendrograms in this study were generated by Q-mode cluster analysi s of locality collection DCA coordinates by UPGMA of the Euclidean distance coef ficient from the upper Etchegoin Siphonalia zone. Fuzzy-mode partitioning was used to arrive at the c luster groups (shaded) annotated in Figures 4.10A,C and 4.12A, B. Single locality clusters are generally monospecific.

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92 Figure 4.11B. Dendrogram from the upper San Joaquin Pecten zone.

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93 Figure 4.12A. Siphonalia zone cluster groups confirmed by NMDS. NMDS was employed to cross-check the congruency and rigor of the clustering in identifying clustergroup community associations. Siphonalia zone cluster groups (Fig. 4.10A-C, 4.11A-B) were precisely resolved.

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94 Figure 4.12B Pecten zone cluster groups confirmed by NMDS. Overlapping clusters groups 1, 2, and 5 are geographically related rathe r than community associations.

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95 Figure 4.13. Bathymetric ranges of Siphonalia zone taxa (A) an d method of water paleodepth determination from DCA (B). A. Paleodepth was determined for each locality collection by correlation of DC2 scores to occurren ces of bathymetrically restricted extant species present, or general bathymetric ranges for genera where the species are extinct, assuming that habitat preferences for these taxa ha ve not changed since the Pliocene. Sources of ecological data are given in Figure 4.10 Localities A-H refer to localities where these species were found (noted on Fig. 4.10B ). B. The relationship between DC2 score and water paleodepth varied between sample in tervals and a single relationship could not be applied throughout all sample interval s. In this example the depth ranges for the bathymetrically restricted taxa from the Siphonalia zone were plotted on a y axis of paleo-water depth versus the x axis of DC2 score of the locality collection where the taxa were present (Fig. 4.10A). For example, in localit y collection A the co-occurrence of Littorina mariana (species extinct; genus living in the intertidal z one, Keen, 1963; Fig. 4.10A) and Nuccella etchegoinensis (species extinct; genus living in the intertidal z one to 1 m water depth, Morris et al., 1980; Fig. 4.10A) e stablishes this locality as representative of the intertidal zone with a zero paleo-water dept h. At locality D bathymetrically restricted species Protothaca staminae (bathymetric range of intertidal to 10m, Coan et al., 2000; Fig. 4.10A) co-occurs with Pseudocardium densatum (species extinct; genus living in waters 1-15 m, Sasaki et al., 2004; Fig. 4.10A) suggesting the apparent depth the fauna from this locality lived at as ~1-10 m. A t localities E and F the co-occurrences of Pseudocardium densatum and Patinopecten lohri (species extinct; genus living in waters 10-200 m, Coan et al., 2000; Fig. 4.10A) sug gests that the apparent depth the faunas from these localities lived at as ~10-15 m. At locality H Protothaca staminae cooccurs with Pseudocardium densatum suggesting the apparent depth the fauna from this locality lived at as ~1-10 m. However, the greater DC2 scores of ~0.6-0.9 at localities E and F (probable paleo-water depths ~10-15 m) when co mpared with the DC2 score of

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96 (Figure 4.13, Continued) zero at locality H (apparent paleo-water depths ~110 m) suggests a possible water depth a locality H 10 m. A trendline was empirically established that best accounted for the DC2 score o f intertidal taxa at locality A with DC2 scores of the locality collections D-F and H and th e slope of this trendline used to calculate paleo-water depths for all localities. T his trendline suggests that at locality E Patinopecten lohri made have lived in water as shallow as ~9 m, above the range of living Patinopecten while at locality H Protothaca staminae lived in 12 m water depths and below the modern depth range of this species. Another interpretation of the paleobathymetric distributions of these two species is that they have been taphonomically displaced outside of the true depth ranges they liv ed. These paleobathymetric are offsets interpreted as indicative of the underlying uncerta inty in this study of the correlation of DC2 score and water depth ranges of bathymetrically restricted taxa. However, this uncertainty of ~2 m in calculated paleo-water dept hs is comparable to the uncertainty in paleo-water depth of ~3 m as calculated from DCA s cores by Scarponi and Kowalewski (2004) from Quaternary faunas of the Po Plain, Ital y. Water depths for the balance of the locality collections in a sample interval were calc ulated from the relationship thus established. This method was applied to DC2 scores from the individual stratigraphic intervals to arrive at a temporal model of paleo-wa ter depth in the Pliocene SJB. Calculated water depths from Etchegoin group strati graphic intervals range from intertidal to a maximum of ~25 m at peak basin flood ing during Patinopecten zone deposition (Fig. 4.14).

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97 values and calculated water depths range from inter tidal (zero paleo-water depth) whereas a score of zero corresponded to a maximum paleo-wat er depths of ~25 m at peak basin flooding during deposition of the Patinopecten zone (basal uppermost Etchegoin) sediments depending on the composition of the fauna from a particular stratigraphic interval (Fig. 4.10A-B, 4.13). Paleowater depths w ere smoothed to compensate for faunal patchiness by averaging water depths determined fro m DC1 in10 m stratigraphic sample intervals (Fig. 4.14). Discussion The Pliocene record of the SJB represents a wide ra nge of environmental settings differing from more open-marine shelfal environment s of the nearby ocean and having a profound effect on the how molluscan faunas were sp atially distributed within the basin. The paleohydrologic history of the Pliocene SJB is one of generally brackish conditions punctuated by periods of near-normal to normal mari ne conditions during periods of eustatic highstand (Stanton and Dodd, 1970; Bowerso x, 2005). Extreme spatial and temporal environmental changes are typical of margi nal ocean basins with dramatic consequences on the hydrologic, sedimentary, geoche mical, and ecologic systems inside the basin (Giosan, 2004) that control the local and regional spatial distributions of the molluscan faunas as well as their temporal structur e. Stanton and Dodd (1970, 1972) described 11 depositional cycles of the uppermost E tchegoin and San Joaquin Formations basin-margin facies represented by the faunal zones of Woodring et al. (1940; Fig. 4.2). A complete cycle commences with basin flooding at e ustatic highstand then through regression to eustatic lowstand (Stanton and Dodd, 1972). Environmental variations associated with these eustatic cycles had profound effects on the composition of the molluscan fauna in the Pliocene San Joaquin Basin b eginning with diverse marine or near-normal marine faunas at basin flooding to lowdiversity faunas tolerant of the brackish conditions leading into the next cycle of basin flooding (Bowersox, 2005; Fig. 4.3-4.4). The communities resolved in this study range from t he deeper-water PatinopectenChione community to the intertidal Mya-Solen community and defined the hard substrate/rockassociated Ostrea-Mytilus and Littorina communities (Fig. 4.15). However, molluscan communities previously described from the uppermost Etchegoin and upper San Joaquin by Stanton and Dodd (1970) an d Dodd and Stanton (1975) could not be fully resolved. A comparison of mollusc com munities described from the late Neogene of California and this study is given in Ta ble 4.3. Four factors may contribute to the differences between this study and the previous studies of Stanton and Dodd (1970) and Dodd and Stanton (1975): 1) this study focuses on marine molluscan communities and thus does not include the freshwater Juga community of Dodd and Stanton (1975); 2) the larger locality collection database of this stu dy allowed the resolution of two marine communities not previously recognized by Stanton an d Dodd (1970) and Dodd and Stanton (1975); 3.) the improvement and increased sophistication of multivariate statistical techniques available to this study did not exist at the time of the pioneering studies by Stanton and Dodd (1970) and Dodd and Sta nton (1975); and 4) that, as in

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98 Figure 4.14. Paleowater depth averaged in 10 m stratigraphic i ntervals. An overall shoaling trend during Etchegoin group deposition is demonstrated. Abrupt basinflooding (Fig. 4.2-4.3) is indicated during deposit ion of the upper Etchegoin and upper San Joaquin.

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99 Figure 4.15. Stratigraphic distributions (A) and distributions by water depths (B) of communities recognized in this study. A. The communities record in the Jacalitos and lower Etchegoin below the 1300 m stratigraphic leve l is biased towards more shorelinedistal Patinopecten-Chione (community 1) through Macoma-Cryptomya (community 3) communities. Erosional truncation of the Jacalitos and lower Etchegoin on the basin margin during post-Pliocene folding and uplift of t he Temblor Range resulted in the loss of more shoreline-proximal and intertidal facies we st of the present Jacalitos and lower Etchegoin outcrop belt. Shallow-water communities represented in the section towards the end of Etchegoin deposition are coincident with eustatic regression and increasing brackishness (Fig. 4.3). During eustatic transgres sion and deposition of the basal San Joaquin Cascajo Conglomerate generally deeper-water normal-marine PatinopectenChione to brackish-tolerant Patinopecten-Macoma and Mya-Macoma (community 4) communities are prevalent. During deposition of t he overlying lower San Joaquin Neverita zone, conditions in the SJB became more brackish a nd the PatinopectenMacoma and Mya-Macoma communities dominated until the marine transgressi on at the advent of upper San Joaquin Pecten zone deposition. Above the 2000 m stratigraphic

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100 (Figure 4.15, Continued) level there is a shift from deeperto shallower-w ater brackishtolerant to brackish-water communities in the secti on culminating with Ostrea-Mytilus to Tidal Flat communities (communities 5-7) remaining at the end of upper San Joaquin deposition. B. Mean preferred water depths generally decrease fro m the PatinopectenChione to the Tidal Flat community. The Mya-Macoma community shows a departure towards higher mean preferred water depth consisten t with the nearly identical modern Macoma balthica community of northern Europe that occurs in waters from intertidal to 10 m.

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101 Table 4.3. Correlation of molluscan communities determined i n this study with previous studies. Communities identified in previous studie s of Etchegoin group faunas and a similar late Miocene fauna from northwestern Califo rnia are correlated with those determined in this study. The San Francisco Bay co mmunities was the first model applied to the Etchegoin group fauna. Like Dodd an d Stanton (1975), I was unable to resolve the differences between Stanton and Dodd’s Inner Bay communities III-IV and VI-VII. The shallow-water Macoma balthica Transported, and Cryptomya californica communities recognized by Watkins (1974) in the lat e Miocene Wimer Formation most closely correlate to the shallow-water communities determined in this study. Sources:1Stanton and Dodd (1970), 2Dodd and Stanton (1975), 3Watkins (1974).

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102 Dodd and Stanton (1975), the inability to resolve t he minor differences between Stanton and Dodd’s (1970) four divisions associated with th e inner-bay communities (Table 4.3). Environmental Controls on Faunal Distributions The primary controls of substrate and water depth p references identified herein as acting on the local and regional spatial distributi ons of the Etchegoin group molluscan fauna and its communities differ from those primary paleooceanographic controls of salinity and temperature identified by Bowersox (20 05) as driving the dynamics of the temporal structure (migration, diversification, and extinction) of these faunas (Chapter 6). Primary environmental controls on the spatial distr ibution of intertidal and nearshore molluscs have been attributed to many factors: subs trate (Tunberg, 1981; Brenchley, 1982; Wignall, 1993; Cattaneo-Vietti et al., 2000; Teske and Woolridge, 2003; Denadai et al., 2005; Lourido et al., 2006), water depth (R enaud-Mornant, 1971; Cattaneo-Vietti et al., 2000), salinity (Gunter, 1955; Frsich, et al. 1995; Teske and Woolridge, 2003; Boehs et al., 2004), wave action (Thrush et al., 19 96; Valds-Gonzlez, et al., 2004), oxygen content of the water (Wignall, 1993), primar y productivity and the competitive availability of nutrients (Peterson, 1982; Fell et al., 1982), predation (Peterson, 1982; Ambrose, 1991; Thrush, 1999), and macrophyte wrack cover (Dugan et al., 2000). In a study of molluscs in the Raunefjorden of western No rway, Tunberg (1981) found that most molluscs show a substrate preference and distr ibution correlated with sediment grain size. In this study, locality collections fr om six sample intervals showed strong substrate control by the distribution of clustered locality collections along DC1: upper Jacalitos, Patinopecten zone, Siphonalia zone (Fig. 4.10A, C), Littorina zone, Trachycardium zone, Acila zone, and upper Mya zone. These substrate-controlled distributions of Etchegoin group molluscs are consi stent with the distributions of molluscs on modern beaches and in nearshore waters. Comparatively few faunas from the Littorina community reflect the patchy distribution of pebbl e-size conglomeratic sediments in the Etchegoin group section (cf. Stant on and Dodd, 1972; Loomis, 1990). Mean paleo-water depths determined from DCA represe nt a range from intertidal to ~20 m at maximum basin flooding (Fig. 4.14). Oth er than the short period of basin flooding during deposition of the uppermost Etchego in and in the middle upper San Joaquin, the general trend was one of shoaling of t he SJB during the Pliocene (Bowersox, 2004; Fig. 4.14). This shoaling was coincident wit h the slowing of basin margin subsidence leading to sediment filling of the avail able basin margin accommodation space and sediment bypass to the central basin (Bow ersox, 2004, 2005). Declining water depth during deposition of the uppermost Etchegoin (Fig. 4.14, 1500-1700 m stratigraphic level) and coincident increasing brac kishness lead to the extinction at the end of Etchegoin deposition (Fig. 4.3, ~4 Ma). The paleo-water depth range for the northwest SJB m argin determined from DCA in this study (Fig. 4.14) are much shallower than p revious interpretations (~2-50 m., Stanton and Dodd, 1970, 1972, 1976, 1997; Dodd and Stanton, 1975; intertidal to ~150 m, Loomis, 1988, 1990). Stanton and Dodd (1970, 19 72, 1976, 1997) and Dodd and Stanton (1975) calibrated their molluscan biofacies and paleoenvironments to analogous

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103 faunas living in San Francisco Bay, California, in water depths ranging from ~2-50 m with median depths for these modern faunas ranging from ~5 in their inner bay/oyster bank biofacies to ~25 m in their outer bay biofacies (Stanton and Dodd, 1970). Loomis (1990) interpreted and summarized the Etchegoin gro up molluscan paleoecology and paleoenvironments from Kreyenhagen Hills and Kettle man Hills locality collections by environmental setting (unprotected shoreline, prote cted shoreline, bay/estuary), water depth, and substrate ranging from mud to gravel and rocks. Loomis (1990) interpreted paleo-water depths for the northwest SJB margin as the maximum depths that the molluscan faunas could have lived and thus arrived at paleo-water depths of intertidal to ~150 m and well outside of those interpreted by Stan ton and Dodd (1970, 1972, 1976, 1997) and Dodd and Stanton (1975). These prior stu dies approach the problem of determining the depth represented by a particular f auna by analogy to the environmental ranges of extant taxa. While this is a valid metho d the scale is subjectively broad and smooths within-sample variation. Samples with mino r compositional differences among the most frequently occurring taxa are easily const rued as representing environmental correspondence when such compositional differences are reflective of local habitat heterogeneity. The subjectivity underlying uniform itarian analogy in paleoecology may compromise the evaluation of those environmental co ntrols on faunal distribution to the point of ascribing distribution to erroneous parame ters or ranges of parameters. This is the flaw in the paleoecological interpretation of L oomis (1990). The value of DCA is the subjectivity is removed from the evaluation and the environmental variables and their magnitudes so determined from DCA plausibly account for observed distributions of taxa. The Pliocene SJB paleoclimate has been broadly inte rpreted in discussions of the marine paleoenvironment. Globally the early-mid Pl iocene warm period (~4.5-3.0 Ma) was characterized by ~3 C higher global surface tem peratures and 10-20 m higher sea level than today (Ravelo et al., 2004). Modern cen tral California ocean temperature averages 13.2 C (Loomis, 1988) whereas the marine climate through deposition of the lower Etchegoin was relatively warmer and equitable becoming variably cooler during upper Etchegoin and San Joaquin deposition (Fig. 4. 7, 4.11). Loomis (1988) suggested an average marine temperature of 14.3 C in the Coa linga region during the latest Miocene and Pliocene based on faunal elements of th e Santa Margarita and Etchegoin group. Hall (2002) interpreted the post-Santa Marg arita paleoclimate of coastal California and the SJB to be temperate based on 4968% of the fauna indicating temperatures of 10-12 C. However, the faunal comp osition of the Etchegoin group suggests warmer temperatures inside the SJB and Pri est Valley Strait as compared to the correlative and paleogeographically related cool-wa ter fauna from the coastal Purisima Formation (Powell, 1998). The warmer ET inside the SJB (Fig.9) suggests that outer tropical conditions of Hall (1960) continued throug h the Early Pliocene and stemmed from the restricted connection through the Priest V alley Strait limiting influx of cooler Pacific water the fact that it was so shallow also undoubtedly played a role. Peak ET inferred from Etchegoin group macrofaunas (Fig. 4.9 ) increased during the early-mid Pliocene warm period from ~14 C at 5.3 Ma to ~15 C by 4.7 Ma then generally

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104 declined to a ~11 C thermal minimum at 3.95 Ma coin cident with sea-level lowstand (Wornardt et al., 2001) at the end of Etchegoin dep osition (Fig. 4.1, 4.3). Warmer than modern sea-surface temperature (SST) for the adjace nt Pacific Ocean 3.29-2.97 Ma (Dowsett et al., 1999) suggests a final period of w arm, wet terrestrial climate in the SJB. ET in the SJB showed a general warming trend beginn ing ~3.8-3.2 Ma during deposition of the lower San Joaquin Formation (Fig. 4.3, 4.9), reaching peak temperatures of ~17 C ~3.4 Ma then declining to ~15 C by 3.0 Ma. ET decli ned after ~2.5 Ma through the Late Pliocene in concert with the onset of northern hemi sphere glaciation (Raymo et al., 1989) to a thermal minimum of <10 C at 2.3 Ma shortly be fore the closure of the Priest Valley Strait and the end of San Joaquin deposition (Fig. 4.3, 4.9). Community Distributions Environmental controls on community distributions differ from those paleoceanographic parameters controlling fauna comp osition and range expansion, diversification, endemism, and extinction described in previous studies (Adegoke, 1969; Stanton and Dodd, 1970; Dodd and Stanton, 1975; Loo mis, 1990; Bowersox, 2005). Multivariate analysis by ordination and clustering effectively resolved seven distinct molluscan communities in this study whose compositi ons were controlled by substrate and paleo-water depth. Stratigraphic distributions and distributions by water depths of each community is given in Figure 4.15A-B. Mean pr eferred water depths generally decrease from the Patinopecten-Chione to the Mya-Solen community with the exceptions of the Mya-Macoma Ostrea-Mytilus and Littorina communities (Fig. 4.15B). The Mya-Macoma community shows a departure towards higher mean pr eferred water depth than the general trend. This community is comparab le to the Macoma balthica community described by Watkins (1974 and sources ci ted therein) from the upper Miocene Wimer Formation of coastal Del Norte County northwest California, as nearly identical to the modern Macoma balthica community of northern Europe occurring in waters from intertidal to 10 m. Mean depth range o f the Etchegoin group Mya-Macoma community is 8.6 m (Fig. 4.15B) reflective of commu nity elements with depth ranges to ~10 m ( Pseudocardium Clinocardium and Protothaca ) in upper Etchegoin locality samples. In the Jacalitos and lower Etchegoin below the 1300 m stratigraphic level (Fig. 4.2), the community record is biased towards more s horeline-distal Patinopecten-Chione through Macoma-Cryptomya communities (Fig. 4.15A-B). However the lack of s hallowwater communities and apparent domination of deeper -water communities represented in the Jacalitos and lower Etchegoin is due to erosion al truncation of the Jacalitos and lower Etchegoin on the basin margin during post-Pliocene folding and uplift of the Temblor Range and consequent loss of more shoreline-proxima l and intertidal facies that would have lain to the west of the present Jacalitos and lower Etchegoin outcrop belt. Complete sections of these lower Etchegoin group strata woul d likely have displayed temporal and spatial distributions of communities comparable to the better represented and well-preserved sections of upper Etchegoin and San Joaquin exposed on the eastern flank of the Kreyenhagen Hills and in the nearby Kettlema n Hills (Fig. 4.15A-B, 4.16A-L).

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105 The greater number of shallow-water communities rep resented in the section towards the end of Etchegoin deposition (Fig. 4.15A) coincides with eustatic regression and increasing brackishness (Fig. 4.3) and basinward mi gration of basin-margin biofacies not preserved west of the Kreyenhagen Hills–Kettleman H ills area lower in the section. The tidal-flat community that last occurred during depo sition of the uppermost Jacalitos recurs during deposition of the uppermost Etchegoin (Fig. 4.15A). During eustatic transgression and deposition of the basal San Joaqu in Cascajo Conglomerate generally deeper-water, normalmarine Patinopecten-Chione to brackish-tolerant Patinopecten-Macoma and Mya-Macoma communities are prevalent (Fig. 4.15A). As conditions in the SJB became more brackish during d eposition of the overlying lower San Joaquin Neverita zone, the deeper-water, normal-marine Patinopecten-Chione community was succeeded by the brackish-tolerant an d cooler-water Patinopecten-Macoma and Mya-Macoma communities and does not reappear in the section until the marine transgression at the onset of upper San Joaquin Pecten zone deposition (Fig. 4.15A-B). Figures 4.16A-H show the changes in distribution of Etchegoin group mollusc communities beginning with deposition of the upper Etchegoin through the end of upper San Joaquin deposition (~4.4-2.2 Ma, Fig. 4.2). The upper Etchegoin record begins with the deeper-water, normal-marine Patinopecten-Chione community present east of the Kreyenhagen Hills during deposition of the lower in terval of the upper Etchegoin (Fig. 4.16A). Uplift of the Kreyenhagen Hills prior to d eposition of the Patinopecten zone led to shallowerwater and brackish-water tolerant Patinopecten-Macoma community dominant west of the Kettleman Hills (Fig. 4.16B) a lthough maximum water depths in the Coalinga region reached ~25 m at this time. Slo wing basin-margin subsidence and concomitant shallowing during deposition of the Macoma zone led to tidal-flat development south of the central Kettleman Hills No rth Dome adjacent to the shallow-water Mya-Macoma community and mussel beds of the Ostrea-Mytilus community (Fig. 4.16C). The identical relationship of the Mya-Macoma community adjacent to mussel beds of the Ostrea-Mytilus community occurs during this period on the shoaling axis of the Coalinga Anticline during structural uplift (Fig. 4.16C). During marine transgression in the Siphonalia zone, the deeper-water Patinopecten-Chione community returned to much of the region and submer ged the growing Coalinga Anticline, Kettleman Hills North Dome, and the cent ral Kreyenhagen Hills (Fig. 4.16D). Tidal flats developed south of the Kettleman Hills South Dome and on what would become the eastern flank of the Jacalitos Anticline (Fig. 4.16D). Structural growth of the Coalinga Anticline caused the area across the antic linal axis to become emergent by Pseudocardium zone deposition (Fig. 4.16E), and it remained so u ntil the marine transgression marking the onset of deposition of th e upper San Joaquin Pecten zone. Increasingly cooler and brackish conditions coincid ent with eustatic regression during deposition of the Pseudocardium zone (Fig. 4.2-4.3) saw the succession of the Patinopecten-Chione community by the Patinopecten-Macoma community, the patchy development of mussel beds of the Ostrea-Mytilus community in the central Kreyenhagen Hills and adjacent central Kettleman Hills North Do me (Fig. 4.16E), and the extinction of

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106 Figure 4.16A. Distribution of communities during upper Etchegoi n (lower interval) deposition.Figure 4.16B. Distribution of communities during deposition of t he uppermost Etchegoin Patinopecten zone.

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107 Figure 4.16C. Distribution of communities during uppermost Etche goin Macoma zone deposition.Figure 4.16D. Distribution of communities coinciding with a majo r transgression and a period of high productivity during deposition of th e uppermost Etchegoin Siphonalia zone.

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108 Figure 4.16E. Distribution of communities during deposition of t he uppermost Etchegoin Pseudocardium zone. The extinction of Pseudocardium densatum occurs in this zone.Figure 4.16F. Distribution of communities during deposition of t he uppermost Etchegoin Littorina zone.

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109 Figure 4.16G. Distribution of communities during deposition of t he lower San Joaquin Cascajo Conglomerate member.Figure 4.16H. Distribution of communities during deposition of t he lower San Joaquin Neverita zone.

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110 Figure 4.16I. Distribution of communities during deposition of t he upper San Joaquin Pecten zone. The Pecten zone represents the last major Pliocene SJB transg ression. Figure 4.16J. Distribution of communities during deposition of t he upper San Joaquin Trachycardium zone.

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111 Figure 4.16K. Distribution of communities during deposition of t he upper San Joaquin Acila zone. Figure 4.16L. Distribution of communities during deposition of t he upper San Joaquin Mya zone.

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112 Figure 4.16A-L. Distributions of upper Etchegoin (A-F) through u pper San Joaquin (GL) communities. A. The upper Etchegoin record shows the progressive e volution from the deeper-water normal marine Patinopecten-Chione community east of the Kreyenhagen Hills to B. the shallower-water and brackish-water tolerant PatinopectenMacoma dominant to the eastern flank of the Kettleman Hil ls during deposition of the Patinopecten zone. C. Shallowing during Macoma zone deposition led to tidal flats developing south of the central Kettleman Hills Nor th Dome adjacent to the shallowwater Mya-Macoma community and mussel beds of the Ostrea-Mytilus community. D. Marine transgression during deposition of the Siphonalia zone returned the deeper-water Patinopecten-Chione community to much of the region. Tidal flats deve loped south of the Kettleman Hills South Dome and on the eastern f lank of the Jacalitos Anticline. E. Increasingly cooler and brackish conditions coincid ent with the deposition of the Pseudocardium zone saw the succession of the Patinopecten-Chione community by the Patinopecten-Macoma community and the patchy development of mussel bed s of the Ostrea-Mytilus community in the central Kreyenhagen Hills and adj acent central Kettleman Hills North Dome. F. Coincident with cooling and increasing brackishness during eustatic regression through the end of Littorina zone deposition communities distribution became increasingly patchy. By the en d of Etchegoin deposition at 4 Ma the Jacalitos Anticline, southern Kreyenhagen Hills, an d the Kettleman Hills Middle and South Domes are interpreted as emergent. The boun dary between the Littorina zone and overlying Cascajo Conglomerate marks the major exti nction at the end of Etchegoin deposition. G. Eustatic transgression during the deposition of th e basal San Joaquin Cascajo Conglomerate returned normal marine waters to the SJB. Complex habitats developed with deposition of coarse clastics led to very patchy distribution communities from the central Kreyenhagen Hills to the Kettleman Hills and shoreline recession to the southwest. H. Increasing brackishness during deposition of the Neverita zone caused the succession of the Patinopecten-Chione community by the brackish-tolerant PatinopectenMacoma east of the Kreyenhagen Hills and brackish-water Macoma-Cryptomya community to the west and south. Tidal flats devel oped in the southern Kreyenhagen Hills and adjacent Kettleman Hills South Dome and o n the northern Kettleman Hills area. I. Eustatic transgression at the beginning of upper Sa n Joaquin Pecten zone deposition at 3.1 Ma allowed the range expansion of normal-marine communities from the Pacific coast back into the SJB. By ~2.9 Ma basin infilling (Bowersox, 2004) and eustatic regression (Fig. 4.2-4.3) led to the development of brackish tidal marshes fringing the Coalinga region inhabited by the brackish-water Macoma-Cryptomya community. J. A shorter-term eustatic transgression during Trachycardium zone deposition was insufficient to flood the SJB to the extent of the transgression during Pecten zone deposition leading to patchy distribution of normal -marine to brackish-water communities throughout the region. K. Although the SJB was again flooded during deposition of the Acila zone the basin was very shallow (Bowersox, 2004 ) and slightly brackish (Fig. 4.2-4.3, ~2.4 Ma). The normal-marine Patinopecten-Chione community was restricted to the area nearest the Priest Valle y Strait connection to the Pacific while tidal flat and a shallow-water brackish tidal marsh patch inhabited by the Macoma-

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113 (Figure 16, Continued) Cryptomya community occupied the central Kettleman Hills North Dome. East of the Kettleman Hills the centra l basin was inhabited by the brackish-tolerant Patinopecten-Macoma community. L. At the time of upper Mya zone deposition the shoreline from the Kettleman Hills South Dome north west to the northern Kettleman Hills North Dome was lined with monospeci fic Dendostrea? vespertina oyster beds ( Littorina community) and a large patch of Ostrea-Mytilus community primarily composed of Dendostrea? vespertina Mytilus trossulus and Littorina mariana The end of upper Mya zone deposition coincides with the final closure o f the Priest Valley Strait and loss of connection with the Pacific Ocean. All marine taxa became extinct in the SJB with the closure of the Priest Valley Strait at ~2.2 Ma (Fig. 4.3). Map annotations: WC Waltham Canyon, JC Jacalitos Creek, ZC Zapato-C hino Creek, CC Canoas Creek, BK Big King Creek, TC Tar Canyon. Sources: Woo dring et al. (1940), open circles; Adegoke (1969), open diamonds; Loomis (1990), open squares; this study, open triangles.

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114 the Etchegoin index bivalve Pseudocardium densatum at the end of Pseudocardium zone deposition. Coincident with the cooling and increa sing brackishness during eustatic regression through the end of Littorina zone and Etchegoin deposition, community distribution became increasingly patchy (Fig. 4.16F ). Non-marine facies of the Etchegoin exposed on the Jacalitos Anticline, in the southern Kreyenhagen Hills (Loomis, 1990) and in the Kettleman Hills Middle and South Domes (Wood ring et al., 1940) are indicative of these areas being emergent at the end of Etchegoin deposition at 4 Ma (Fig. 4.16F). The San Joaquin section records multiple marine tra nsgressions up to the final closure of the Priest Valley Strait and the final e xtinction of marine taxa in the SJB. Marine transgression during the deposition of the b asal San Joaquin Cascajo Conglomerate member returned normal-marine waters t o the SJB. Complex habitats developing with the deposition of coarse clastics l ed to very patchy distribution communities from the central Kreyenhagen Hills to t he Kettleman Hills (Fig. 4.16G). The shoreline had receded to the southwest submergi ng the Kettleman Hills Middle and South Domes as well as the Jacalitos Anticline (Fig 4.16G). Restriction of the Priest Valley Strait and increasing brackishness in the SJ B during deposition of the Neverita zone (Fig. 4.3) caused the succession of the Patinopecten-Chione community by the brackish-tolerant Patinopecten-Macoma community east of the Kreyenhagen Hills and brackish-water Macoma-Cryptomya community to the west and south (Fig. 4.16H). Wit h falling sea level (Fig. 4.2-4.3), tidal flats are i nterpreted to have developed in the southern Kreyenhagen Hills (Loomis, 1990) and adjacent Kettl eman Hills South Dome (Stanton and Dodd, 1970, 1972; Dodd and Stanton, 1975), and in the northern Kettleman Hills area (this study, Fig. 4.16H). Eustatic transgress ion at the beginning of upper San Joaquin Pecten zone deposition at 3.1 Ma (Fig. 4.2-4.3) allowed t he range expansion of normal-marine communities from the Pacific Coast ba ck into the SJB ( Fig. 4.16I) followed by rapid species diversification (Stanton and Dodd, 1997; Bowersox, 2005). Basin infilling (Bowersox, 2004) and eustatic regre ssion beginning at ~2.9 Ma subsequent to the basin flooding (Fig. 4.2-4.3) led to the development of brackish tidal marshes fringing the SJB (Loomis, 1990; Reid, 1995) In the Coalinga region, the brackish-water Macoma-Cryptomya community extended from tidal flats developed in the southern Kettleman Hills South Dome area throug h the Kreyenhagen Hills to the Jacalitos Anticline and on the Coalinga Anticline w hich was submerged for the first time since deposition of the uppermost Etchegoin Siphonalia zone (Fig. 4.2-4.3, ~4.1 Ma; Fig. 4.16I). A shorter-term eustatic transgression duri ng Trachycardium zone deposition (Fig. 4.2-4.3) was insufficient to flood the SJB to the e xtent of the transgression during Pecten zone deposition (Fig. 4.16J). The Coalinga Anticli ne re-emerged and remained so until the end of San Joaquin deposition at 2.2 Ma. The d eeper-water Patinopecten-Chione community was restricted to the area between the no rthernmost Kettleman Hills and the Coalinga Anticline while the more brackish-tolerant Patinopecten-Macoma community inhabited the area between the Kettleman Hills and the Kreyenhagen Hills with the brackish-water MacomaCryptomya community in the Kreyenhagen Hills area (Fig. 4.16J). Patches of the shallower brackish-water Mya-Macoma community inhabited the southern Kettleman Hills North Dome and central Mid dle Dome. Ostrea-Mytilus

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115 community patches were present at the northern end of the Kreyenhagen Hills and southern Kettleman Hills Middle Dome adjacent to ti dal flats (Fig. 4.16J). Although the SJB was again flooded during deposition of the Acila zone (Fig. 4.2-4.3) the basin remained very shallow (Bowersox, 2004 ) and slightl y brackish (Fig. 4.3, ~2.4 Ma). The normal-marine Patinopecten-Chione community was restricted to the area nearest the Priest Valley Strait connection to the Pacific betw een the Jacalitos Anticline and Kreyenhagen Hills to the western Kettleman Hills No rth Dome area and northeast of a large area interpreted as tidal flats (Fig. 4.16K). A tidal flat and adjacent shallow-water brackish tidal marsh patch inhabited by the Macoma-Cryptomya community occupied the central Kettleman Hills North Dome while east of th e Kettleman Hills the central basin was inhabited by the brackish-tolerant Patinopecten-Macoma community (Fig. 4.16K). During the upper Mya zone, the area west of the Kettleman Hills was eme rgent (Fig. 4.16L). The shoreline from the Kettleman Hills Sou th Dome northwest to the northern Kettleman Hills North Dome was lined with intertida l-subtidal monospecific Dendostrea? vespertina oyster beds ( Littorina community) and a large patch of Ostrea-Mytilus community primarily composed of Dendostrea? vespertina Mytilus trossulus and Littorina mariana All marine taxa became extinct with the closure of the Priest Valley Strait at ~2.2 Ma (Fig. 4.3) followed by filling of the SJB by a freshwater lake and deposition lacustrine and fluvial sediment s of the Late Pliocene-Late Pleistocene Tulare Formation.Conclusions Whereas the Pliocene biotic history of the SJB was substantially different than that of nearby open-marine, coastal waters, the dis tribution of molluscan communities was consistent with modern marginal sea-estuarine f aunas. Multivariate statistical methods, including DCA, cluster analysis of UPGMA E uclidean distance, and NMDS, were employed in the analysis of binary (presence-a bsence) faunal data from the Etchegoin group to determine environmental gradient s controlling the spatial and temporal distributions of mollusc species and speci es community associations in the Pliocene SJB. Environmental controls on community distributions differ from those paleooceanographic parameters controlling fauna com position and range expansion, diversification, endemism, and extinction (Bowersox 2005). 1.DCA of 484 locality collections from 15 stratigra phic intervals determined that the primary environmental gradients controlling distrib ution of Etchegoin group faunas were substrate type and paleowater depth. The loca lity collections were distributed along the DCA axis 1 from rocky to mud substrates w hereas paleowater depth distributed locality collections along DCA axis 2 f rom deeper water to intertidal. Greater diversity is generally displayed in communi ties from sand to sandy-mud substrates whereas lower diversity to monospecific communities are generally associated with rocky substrates. Substrate-contro lled distributions of mollusc communities on the northwest margin of the Pliocene SJB were patchy but consistent with those modern communities from comparable subst rates. Paleowater depths

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116 determined in this study range from intertidal to ~2 5 m at maximum basin flooding and are shallower than those interpreted for the re gion in previous studies. 2.Effective temperatures determined for the Etchego in group faunas ranged ~10-16 C. Temperatures show a cooling trend through depositio n of the Etchegoin Formation followed by a variable temperature regime through S an Joaquin Formation deposition. 3.Cluster analysis of Euclidean distance of DCA sco res from each sample interval determined faunal associations, confirmed by NMDS, with similar environmental controls. These cluster-groups were interpreted as representative of seven bivalve-dominated molluscan communities: Patinopecten-Chione, Patinopecten-Macoma, Macoma-Cryptomya, Mya-Macoma, Mytilus-Ostrea, Littorina, and Mya-Solen in rank order from deeper to shallower range of w ater depths and from normal marine-adapted to brackish t olerant and characteristically brackish communities. In general, gastropods are m inor components of these communities and predators were scarce. 4.Temporal distribution of communities, their strat igraphic sequence, reflects both the relative SJB sea-level history and water depths inh abited by individual communities. However the lack of shallow-water communities and a pparent domination of deeperwater communities represented in the Jacalitos and lower Etchegoin are due of erosional truncation of shoreline-proximal and inte rtidal facies during post-Pliocene Temblor Range uplift leaving deeper-water facies pr eserved and exposed in outcrop. During upper Etchegoin and San Joaquin deposition, distribution of shallow-water communities coincides with eustatic regression and increasingly brackish conditions whereas distribution deeper-water communities coinc ides with eustatic transgression. 5.Spatial distribution of communities is patchy and dependent on the interplay between eustatic level and subsidence. At eustatic highsta nds during uppermost Etchegoin Patinopecten and Siphonalia zones deposition and during upper San Joaquin Pecten zone deposition, patchiness was at a minimum and th e deeper-water, normal-marine Patinopecten-Chione dominated the nearshore environments. At eustatic lowstands, and late in the history of the Pliocene SJB, there developed emergent areas and a patchwork of tidal flats, fringing tidal marshes, a nd shallow brackish embayments inhabited by characteristic Mya-Macoma Ostrea-Mytilus and Mya-Solen communities. ReferencesAdegoke, O.S., 1969, Stratigraphy and paleontology of the marine Neogene formations of the Coalinga region, California: University of Cali fornia, Publications in Geological Sciences, v. 80, 241 p., 13 pl. Ambrose, W.G., Jr., 1991, Are infaunal predators im portant in structuring marine softbottom communities: Integrative and Comparative Bio logy, v. 31, p. 849-860. Arnold, R., 1909, Paleontology of the Coalinga dist rict, Fresno and Kings Counties, California: United States Geological Survey, Bulle tin 396, 173 p., 30 pl.

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117 Arnold, R., and Anderson, R., 1910, Geology and oil resources of the Coalinga district, Fresno and Kings Counties, California: United Stat es Geological Survey, Bulletin 398, 354 p. Axelrod, D.I., and Bailey, H.P., 1969, Paleotempera ture analysis of Tertiary floras: Palaeogeography, Palaeoclimatology, and Palaeoecolo gy, v. 6, p. 163-195. Bailey, H.P., 1960, A method of determining the war mth and temperature of climate: Geografiska Annaler, v. 42, p. 1-16. Behrensmeyer, A.K., Frsich, F.T., Gastaldo, R.A., Kidwell, S.M., Kosnik, M.A., Kowalewski, M., Plotnick, R.E., Rogers, R.R., and A lroy, J., 2005, Are the most durable shelly taxa also the most common in the mar ine fossil record?: Paleobiology, v. 31, p. 607-623. Boehs, G., Absher, T.M., and da Cruz-Kaled, A., 200 4, Composition of benthic molluscs on intertidal flats of Paranaga Bay (Paran Bay, B razil): Scientia Marina, v. 68, p. 537-543. Bowersox, J.R., 2004, Late Neogene Paleobathymetry, Relative Sea Level, and Basin Margin Subsidence, Northwest San Joaquin Basin, Cal ifornia: American Association of Petroleum Geologists, Search and Dis covery Article 30029, Bowersox, J.R., 2005, Reassessment of extinction pa tterns of Pliocene molluscs from California and environmental forcing of extinction in the San Joaquin Basin: Palaeogeography, Palaeoclimatology, Palaeoecology, v. 221, p. 55-82. Brenchley, G.A., 1982, Mechanisms of spatial compet ition in marine soft-bottom communities; Journal of Experimental Marine Biology and Ecology, v. 60, p. 1733. Buzas, M.A., and Culver, S.J., 1999, Understanding regional species diversity through the log series distribution of occurrences: Biodiversit y Research, v. 8, p. 187-195. Buzas, M.A., Koch, C.F., Culver, S.J., Sohl, N.F., 1982, On the distribution of species occurrence: Paleobiology, v. 8., p. 143-150. Cattaneo-Vietti, R., Chiantore, M., Schiaparelli, S ., and Albertelli, G., 2000, Shallowand deep-water mollusc distribution at Terra Nova B ay (Ross Sea, Antarctica): Polar Biology, v. 23, p. 173-182. Coan, E.V., Scott, P.H., and Bernard, F.R., 2000, B ivalve seashells of Western North America: Marine Bivalve Mollusks from Arctic Alaska to Baja California: Santa Barbara Museum of Natural History, Monographs Numbe r 2, Studies in Biodiversity Number 2, 764 p. Crampton, J.S., Beu, A.G., Cooper, R.A., Jones, C.M ., Marshall, B., and Maxwell, P.A., 2003, Estimating the rock volume bias in paleodiver sity studies: Science, v. 301, p. 358-360. Denadai, M.R., Amaral, A.C.Z., and Turra, A., 2005, Structure of molluscan assemblages in sheltered intertidal unconsolidated environments : Brazilian Archives of Biology and Technology, v. 48, p. 825-839.

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119 Hall, C.A. and Loomis, K.B., 1992, Geologic Map of the Kreyenhagen Hills-Sunflower (McLure) Valley Area, Fresno, Kern, Kings, and Mont erey Counties, California: Geological Society of America, Map and Chart Series MCH074, 4 Map Sheets, 17 p. Hall, C.A., 2002, Nearshore Marine Paleoclimatic Re gions, Increasing Zoogeographic Provinciality, Molluscan Extinctions, and Paleoshor elines, California: Late Oligocene (27 Ma) to Late Pliocene (2.5 Ma): Geolog ical Society of America, Special Paper 357, 489 p. Hammer, ., Harper, D.A.T., and P. D. Ryan, 2001, P AST: paleontological statistics software package for education and data analysis: P alaeontologia Electronica, v. 4, 9p., accessed February 27, 2006.>Hammer, ., Harper, D.A.T., and P. D. Ryan, 2006, P AST PAlaeontological STatistics, ver. 1.38: , acc essed February 27, 2006. Hayek, L.C., and Buzas, M.A., 1997, Surveying Natur al Populations: New York, New York, Columbia University Press, 563 p. Hill, M.O., and Gauch, H.G., Jr., 1980, Detrended c orrespondence analysis: an improved ordination technique: Vegetatio, v. 42, p. 47-58. Holland, S.M., 2005, The signatures of patches and gradients in ecological ordinations: Palaios, v. 20, p. 573-580. Hoots, H.W., 1930, Geology and Oil Resources Along the Southern Border of San Joaquin Valley, California: United States Geologica l Survey Bulletin 812-D, p. 243-332. Keen, A.M., 1963, Marine Molluscan Genera of Wester n North America: Stanford, California, Stanford University Press, 126 p. Keen, A.M., 1971, Sea Shells of Tropical West Ameri ca, 2nd Edition: Stanford, California, Stanford University Press, 1064 p. Kidwell, S.M., Frsich, F.T, and Aigner, T., 1986, Conceptual framework for the analysis and classification of fossil concentrations: Palaio s, v. 1, p. 228-238. Kulikova, V.A., and Sergeenko, V.A., 2003, Abundanc e and distribution of pelagic larvae of bivalves and echinoderms in Busse Lagoon (Aniva Bay, Sakhalin Island): Russian Journal of Marine Biology, v. 29, p. 81-89, Lam, K., and Morton, B., 2004, The oysters of Hong Kong (Bivalvia: Ostreidae and Gryphaeidae): Raffles Bulletin of Zoology, v. 52, p 11-28. Loomis, K.B., 1988, Paleoenvironmental and paleocli matic interpretation of upper Miocene-Pliocene lithofacies and macrobiota of the Etchegoin Group, Jacalitos Canyon, San Joaquin Valley, California, in Graham, S.A., Studies of the Geology of the San Joaquin Basin: Society of Economic Paleo ntologists and Mineralogists, Pacific Section, v. 60, p. 303-318. Loomis, K.B., 1990, Late Neogene depositional hist ory and paleoenvironments of the west-central San Joaquin Basin, California [PhD the sis]: Stanford, California, Stanford University, 594 p.

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120 Lourido, A., Gestoso, L., and Troncoso, J.S., 2006, Assemblages of the molluscan fauna in subtidal soft bottoms of the Ra de Aldn (north -western Spain): Journal of the Marine Biological Association of the United Kingdom v. 86, 129-140. MacNeil, F.S., 1967, Cenozoic pectinids of Alaska, Iceland, and other northern regions: United States Geological Survey, Professional Paper 553, 57 p. Madin, J.S., Alroy, J., Aberhan, M., Frsich, F.T., Kiessling, W., Kosnik, M.A., and Wagner, P.J., 2006, Statistical independence of esc alatory ecological trends in Phanerozoic marine invertebrates: Science, v. 312, p. 897-900. Marchant, R., 1990, Robustness of classification an d ordination techniques applied to macroinvertebrate communities from the La Trobe Riv er, Victoria: Australian Journal of Marine and Freshwater Research, v. 41, p 493 504. Marchant, R., 1999, How important are rare species in aquatic community ecology and bioassessment? A comment on the conclusions of Cao et al.: Limnology and Oceanography, v. 44, p.1840-1841. Merrill, R.D., 1986, Tidal channels and seaway in P liocene Etchegoin Formation, Coalinga, California, USA [abstract]: International Sedimentological Congress, Sediments Down-Under: 12th International Sedimentological Congress, Canberra, Australia, 24-30 August 1986, Abstracts, p. 211. Miller, K.G., Browning, J.V., Sugarman, P.J., McLau ghlin, P.P., Kominz, M.A., Olsson, R.K., Wright, J.D., Cramer, B.S., Pekar, S.J., and Van Sickel, W., 2003, 174AX leg summary: sequences, sea level, tectonics, and a quifer resources: coastal plain drilling, in Petronotis, K.E., Peters, L.L., McWil liams, A., and Lewis, S.C., eds., Proceedings of the Ocean Drilling Project, Initial Reports, 174AX (Supplement): College Station, Texas, Ocean Drilling Program, p. 1–38. Minchin, D., 2003, Introductions: some biological a nd ecological characteristics of scallops: Aquatic Living Resources, v. 16, p. 521-5 32. Morris, P.A., 1966, A Field Guide to Shells of the Pacific Coast and Hawaii Including Shells of the Gulf of California, 2nd Edition: Bost on, Massachusetts, Houghton Mifflin Company, 297 p. Morris, R.H., Abbott, D.P., and Harderlie, E.C., 19 80, Intertidal Invertebrates of California: Stanford, California, Stanford Universi ty Press, 690 p. Nomland, J.O., 1917, The Etchegoin Pliocene of midd le California: University of California Publications in Geology, v. 10, p. 191-2 54. Oksanen, J., and Minchin, P.R., 1997, Instability o f ordination results under changes in input data order: explanations and remedies: Journa l of Vegetation Science, v. 8, p. 447-454. Peet, R.K., Knox, R.G., Case, J.S., and Allen, R.B. 1988, Putting things in order: the advantages of Detrended Correspondence Analysis: Am erican Naturalist, v. 131, p. 924-934. Peterson, C.H., 1982, The importance of predation a nd intraand interspecific competition in the population biology of two infaun al suspension-feeding bivalves, Protothaca staminae and Chione undatella : Ecological Monographs, v. 52, p. 437-475.

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121 Pillar, V.D., 1999, How sharp are classifications?: Ecology, v. 80, p. 2508-2516. Poore, G.C.B., and Rainer, S., 1974, Distribution a nd abundance of soft-bottom molluscs in Port Phillip Bay, Victoria, Australia: Australia n Journal of Marine and Freshwater Research, v. 25, p. 371-411. Powell, C.L., 1998, The Purisima Formation and Rela ted Rocks (Upper MiocenePliocene), Greater San Francisco Bay Area, Central California Review of Literature and United States Geological Survey Coll ection (now Housed at the Museum of Paleontology, University of California, B erkeley): United States Geological Survey Open File Report 98-594, 101 p. Ravelo, A.C., Andreasen, D.H., Lyle, O.L., and Wara M.W., 2004, Regional climatic shifts caused by gradual global cooling in the Plio cene epoch: Nature, v. 429, p. 263-267. Raymo, M.E., Ruddiman, W.F., Backman, J., Clement, B.M. and Martinson, F.G., 1989, Late Pliocene variation in northern hemisphere ice sheets and North Atlantic deep water circulation: Paleoceanography, v. 4, p. 413-4 46. Reid, S.A., 1995, Miocene and Pliocene depositional systems of the southern San Joaquin Basin and formation of sandstone reservoirs in the Elk Hills area, California, in: Fritsche, E.A., ed., Cenozoic Paleogeography of the Western United States II: Society of Economic Paleontologists and Mineralogis ts, Pacific Section, Book 75, p. 131-150. Renaud-Mornant, J.C., Salvat, B., and Bossy, C., 19 71, Macrobenthos and meiobenthos from the closed lagoon of a Polynesian atoll, Matur ei Vavao (Tuamotu): Biotropica, v. 3, p. 36-55. Romesburg, H.C., 1984, Cluster Analysis for Researc hers: Malabar, Florida, Krieger Publishing Company, 334 p. Rose, R.L. and Colburn, I.P., 1963, Geology of the east-central part of the Priest Valley quadrangle, California. Geology of Salinas Valley a nd the San Andreas Fault: American Association of Petroleum Geologists and So ciety of Economic Paleontologists and Mineralogists, Pacific Sections Annual Spring Field Trip 1963 Guidebook, p. 38-45. Sasaki, K., Sanematsu, A., Kato, Y., and Ito, K., 2 004, Dependence of the surf clam Pseudocardium sachalinense (Bivalvia: Mactridae) on the near-bottom layer for food supply: Journal of Molluscan Studies, v. 70, p 207-212. Scarponi, D., and Kowalewski, M., 2004, Stratigraph ic paleoecology: bathymetric signatures and sequence overprint of mollusk associ ations from upper Quaternary sequences of the Po Plain, Italy: Geology, v. 32, p .989-992. Shi, G.R., 1993, Multivariate data analysis in pala eoecology and palaeobiogeography – a review: Palaeogeography, Palaeoclimatology, and Pal aeoecology, v. 105, p. 199234. Smith, J.P., 1919, Climatic relations of the Tertia ry and Quaternary faunas of the California region: Proceeding s of the California A cademy of Sciences, 4th Series, v. 9, p. 123-173.

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122 Stanton, R.J. and Dodd, J.R., 1970, Paleoecologic t echniques – comparison of faunal and geochemical analysis of Pliocene paleoenvironments, Kettleman Hills, California: Journal of Paleontology, v. 44, p. 1092-1121. Stanton, R.J. and Dodd, J.R., 1972, Pliocene cyclic sedimentation in the Kettleman Hills, California, in Rennie, E.W., ed., Guidebook to Geol ogy and Oil Fields, West Side Central San Joaquin Valley: American Association of Petroleum Geologists, Pacific Section, p. 50-58. Stanton, R.J., and Dodd, 1976, Pliocene biostratigr aphy and depositional environment of the Jacalitos Canyon area, California, in Fritsche, E.A., Ter Best, H., and Wornardt, W.W., eds., The Neogene Symposium: Societ y of Economic Paleontologists and Mineralogists, Pacific Section, p. 85-94. Stanton, R.J. and Dodd, J.R., 1997, Lack of stasis in late Cenozoic marine faunas and communities, central California, Lethaia, v. 30, p. 239-256. Teske, P.R., and Woolridge, T.H., 2003, What limits the distribution of subtidal macrobenthos in permanently open and temporarily op en/closed South African estuaries? Salinity vs. sediment particle size: Est uarine, Coastal and Shelf Science, v. 57, p. 225-238. Thrush, S.F., 1999, Complex role of predators in st ructuring soft-sediment macrobenthic communities: implications of changes in spatial sca le for experimental studies: Austral Ecology, v. 24, p. 344-354. Thrush, S.F., Whitlatch, R.B., Pridmore, R.D., Hewi tt, J.E., Cummings, V.J., and Wilkinson, M.R., 1996, Scale-dependent recolonizati on: the role of sediment stability in a dynamic sandflat habitat: Ecology, v 77, p. 2472-2487. Tkachenko, K.S., 2003, Distribution of the anthozoa n Metridium senile fibriatum (Verril) on rocky sublittoral of the Rimsky-Korsakov Islands Sea of Japan: Russian Journal of Ecology, v. 34, p. 271-276, translated f rom Ekologiya, no. 4, 2003, p. 307-313. Tunberg, B., 1981, Two bivalve communities in a sha llow and sandy bottom in Raunefjorden, western Norway: Sarsia, v. 66, p. 257 -266. Valds-Gonzlez, A., Flores-Rodrguez, P., Flores-G arza, R., and Garca-Ibez, 2004, Molluscan communities of the rocky intertidal zone at two sites with different wave action on Isla Roqueta, Acapulco, Guerrero, M xico: Journal of Shellfish Research, v. 23, p. 875-880. Watkins, R., 1974, Molluscan paleobiology of the Mi ocene Wimer Formation, Del Norte County, California: Journal of Paleontology, v. 48, p. 1264-1282. Wignall, P.B., 1993, Distinguishing between oxygen and substrate control in fossil benthic assemblages: Journal of the Geological Soci ety, v. 150, p. 193-196. Woodring, W.P., Stewart, R., and Richards, R.W., 19 40, Geology of the Kettleman Hills oil field, California: United States Geological Sur vey Professional Paper 195, 170 p., 56 pl.

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123 Wornardt, W.W., Shaffer, B. and Vail, P.R., 2001, R evision of the Late Miocene, Pliocene, and Pleistocene sequence cycles [abstract ]: American Association of Petroleum Geologists Bulletin, v. 85, p. 1710.

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124 Chapter 5 Cross-scale Temporal and Spatial Diversity and Stru cture of Molluscan Faunas from the Pliocene Etchegoin Group, Central Californ ia Abstract The Pliocene Etchegoin group (informal nomenclature ) was deposited in the San Joaquin Basin (SJB), a marginal ocean basin connect ed to the Pacific Ocean through a long, narrow, silling strait. Presence-absence dat a from 484 localities was compiled into 116 ten-meter stratigraphically sequential sample i ntervals, 14 samples by 4th-order eustatic cycle, three samples by formation, and the Etchegoin group in toto to develop a temporal diversity model for the Pliocene San Joaqu in Basin molluscan fauna. Shannon diversity (H) and evenness (E) were calculated for the total and endemic faunas from each locality collection and sample interval. The total species richness of the Etchegoin group consists of ??? molluscan taxa. The group’s fauna is dominated by a few abundant species occurring in most habitats but largely cons ists of uncommon to rare species. In the Etchegoin group fauna, 19% of species account f or 67% of all occurrences with the 33% uncommon species accounting for ~23% of total fa unal diversity. Locality collections (1 diversity) contribute 62% of sample diversity (2) reflecting regional habitat patchiness. Endemic species comprise 30% o f the fauna and account for 42% of2 diversity indicative of their environmental sensiti vity. As compared to 4th-order eustatic variations, diversity between samples (1) accounts for ~80% of the total diversity () consistent with the eustatic control of faunal co mposition. Complex community structure in the Etchegoin group fauna, d emonstrated by higher H and lower E, corresponds to the highest eustatic levels assoc iated with normal marine conditions. Low H and very patchy community distributions corre spond to brackish conditions at eustatic lowstand and increasingly brackish conditi ons as the basin shallowed prior to closure of the connection to the Pacific. Spatial scaling at the regional level shows H and E associated with tidal-flat and bay environments a re consistent with substrate-controlled patchy habitat distribution demonstrated in modern intertidal and nearshore mollusc faunas. Comparison of the Etchegoin group mollusc fauna to the Pliocene fauna of the Santa Maria Basin of central coastal California sho ws greater H in the San Joaquin Basin during the early Pliocene but lower H during the mi ddle and late Pliocene when the San Joaquin Basin was generally brackish and environmen tally variable. As compared to modern central coastal California estuarine faunas, H was higher than modern faunas in the early Pliocene while H of the late Pliocene fau na was comparable to modern California estuarine faunas from Elkhorn Slough and Mugu Lagoon. However, if the effect of time averaging is discounted, peak specie s richness within the Etchegoin group

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125 fauna was ~50% of the modern San Francisco Bay fauna Partitioning 2 diversity between non-endemic and endemic species reveals hab itat segments as either nonendemic/endemic species shared habitat or habitat a vailable solely to endemic species. During eustatic transgression and regression availa ble endemic habitats expand and contract, respectively, at a greater rate than the shared habitat. Invading generalist species quickly fill the shared habitat during transgressio n and displace endemic species during regression. This implies that during the current p eriod of global sea level rise depleted endemic faunas of modern shallow-coastal and oceanmarginal environments will be displaced into the shared-habitat with consequent e xtinction likely if adaptation does not keep pace environmental change. Introduction and Previous Work The controls on abundance and occurrence, species r ichness, diversity, and evenness have been of broad interest to both neonand paleontologists as these have a profound influence on our understanding of biodiver sity through space and time. This interest leads to the examination of the history of late Neogene faunas as models for the prediction of the effects of global climate change on modern nearshore and oceanmarginal invertebrate faunas. The late Neogene rec ord of the San Joaquin Basin (SJB), central California, affords the opportunity to stud y the effects environmental forcings on the spatial and temporal composition of and structu re of essentially modern faunas from a marginal sea in settings comparable to the modern. Although the Etchegoin group (informal SJB nomenclature) includes the record of a biotic history substantially different than that of nearby coastal waters, it is not so un like modern ocean-marginal environments so as to make to the models of this st udy inapplicable to current problems in marine conservation. Previous studies of Etchegoin group molluscs have f ocused on systematics and biostratigraphy (Arnold, 1909; Arnold and Anderson, 1910; Woodring et al., 1940; Adegoke, 1969), paleoecology (Stanton and Dodd, 197 0; Dodd and Stanton, 1975; Loomis, 1990), species diversification (Stanton and Dodd, 1997), and the pattern and causes of extinction (Bowersox, 2005). This study focuses on the species diversity and structure of the Etchegoin group molluscan fauna at increasingly coarse scales from the locality collection to the Etchegoin group fauna as a whole in order to determine spatial and temporal controls on the fauna structure. It w ill be demonstrated that at spatial scales from the individual locality to the Coalinga region that diversity is controlled by local habitat patchiness. Temporal controls on diversity are linked to those large-scale environmental forcings related to climate and eusta sy. The endemic molluscan fauna is examined and its contribution to the total diversit y of the Etchegoin group molluscan fauna from the standpoint of its sensitivity to env ironmental variability and the interaction with the non-endemic fauna. Together, the spatial and temporal controls of molluscan faunal diversity in the Pliocene SJB provide insigh ts into impact of the current phase of global climate change on faunas in modern shallow-c oastal and ocean-marginal environments. The Pliocene southern San Joaquin Basin (SJB) of ce ntral California was a

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126 marginal ocean basin connected to the Pacific Ocean through a long, narrow, and shallow seaway (Fig. 5.1). It was subject to environmental variability driven by eustatic regression coupled with intermittent regional tecto nic interruption of the connection between the SJB and the Pacific Ocean (Fig. 5.1) an d regional climate variation. Thus, the Pliocene Etchegoin group (informal SJB stratigr aphic nomenclature, Fig. 5.2) includes a record of a biotic history substantially different than that of nearby coastal waters. Critical environmental changes occurred in the SJB during deposition of the uppermost Etchegoin and upper San Joaquin formation s. The uppermost Etchegoin Formation records rapid environmental deterioration leading to the regional molluscan extinction in the SJB at ~4 Ma (Bowersox, 2005). Th e upper San Joaquin record is one of favorable marine conditions beginning with rapid basin flooding at ~3.1 Ma deteriorating to brackish conditions and the extinc tion of all marine taxa with the final closure of the Priest Valley Strait at ~2.2 Ma (Fig. 5.2). In their landmark paleoecologic papers, Stanton and Dodd (1970) and Dodd and Stanton (1975) analyzed the physical and biotic cha racteristics of San Francisco Bay, California, as an analog for the Pliocene San Joaqu in Basin. They identified seven molluscan community biofacies in San Francisco Bay through multivariate analysis ranging from normal-marine conditions in outer, mid dle, and inner bay biofacies near the mouth of San Francisco Bay to brackish-water inner bay biofacies in the upper reaches of San Pablo Bay (Stanton and Dodd, 1970). In their l ater study of the Pecten and upper Mya zones of Woodring et al. (1940) in the Kettleman H ills, Dodd and Stanton (1975) refined their biofacies model naming eight correspo nding communities interpreted as occurring in normal-marine outer bay through bracki sh-water inner bay and freshwater environments and demonstrated their lateral relatio nships. Stanton and Dodd (1970, 1972) and Dodd and Stanton (1975), however, did not evaluate those environmental parameters controlling the temporal variations in d iversity and structuring of mollusc communities in the Pliocene SJB. Loomis (1990) interpreted Etchegoin group molluscan paleoecology and paleoenvironments from the presenc e of extant taxa in locality collections from the Kreyenhagen Hills and Kettlema n Hills through application of uniformitarian analogy to extant taxa in the faunas She concluded that the Etchegoin group fauna is composed of taxa primarily character istic of modern bay and estuarine environments many of which were interpreted to have lived in tidal flats. Other than the interpretation of paleobathymetry, in an overall se nse the molluscan paleoecological and paleoenvironmental interpretations for the Kreyenha gen Hills (Loomis, 1990) are consistent with those of the nearby Kettleman Hills (Stanton and Dodd, 1970, 1972, 1997; Dodd and Stanton, 1975).Methodology To develop a temporal diversity model for the Plioc ene San Joaquin Basin molluscs, presence-absence data was compiled from 4 25 localities with verified stratigraphic range information from the past centu ry of literature (Arnold, 1909; Arnold and Anderson, 1910; Hoots, 1930; Woodring et al., 1 940; Adegoke, 1969; Loomis, 1990) and new collections

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127 Figure 5.1. Early Pliocene paleogeography of central Californ ia at ~5 Ma (modified with annotations from Bowersox, 2004a, fig. 1). Locatio n of the SJB with the approximate extent of the Pliocene marginal ocean basin shaded is noted on the map of California. Faults west of the San Andreas fault are not shown. Location of La Honda and Santa Maria Basins are shown relative to the SJB at that time. The modern shoreline and cities locations are shown for reference. Areas of Etcheg oin group fossil localities are noted: A. White Creek Syncline, B. Coalinga Anticline, C. Priest Valley, D. Jacalitos Anticline, E. Kreyenhagen Hills, F. Kettleman Hills, G. Bacon Hills, H. Muddy Creek. The number of locality collections from each area is given in Tab le 5.1. Comparative fossil (location 1) and modern faunas (locations 2-5) are noted on the map of California: 1. Santa Maria Basin Pliocene faunas (Woodring and Bramlette, 1950 ), 2. San Francisco Bay (Packard, 1918b), 3. Elkhorn Slough (MacGinitie, 1935), and 4. Mugu Lagoon (Warme, 1971).

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128 Figure 5.2. Composite stratigraphic section of the Etchegoin group and Pliocene northwest SJB 4th order relative sea level curve. The division of t he San Joaquin Formation into informal lower and upper members at the base of the upper San Joaquin Formation Pecten zone was first used by Woodring et al. (1940) and has been followed in this paper. Subdivisions of the upper Etchegoin-up per San Joaquin section from 12002500 m stratigraphic levels are generalized from Wo odring et al. (1940).

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129 from 59 localities in Etchegoin group outcrops loca ted in the foothills of the western and southern margins of the San Joaquin Basin during 19 99-2004 (Fig. 5.1, Table 5.1). Temporal resolution in the form of a near-uniform v ertical stratigraphic distribution of the 484 locality collections, i.e. gaps less than ~30 m between stratigraphically successive locality collections, is best in the basal Jacalito s, uppermost Etchegoin, and upper San Joaquin formations (Fig. 5.3). The 59 new collecti ons confirm previous results which have demonstrated that the Etchegoin group fauna li ved in shallow-water, lowdepositional gradient foreshore, tidal-flat, and ti dal-channel environments. Specimens showed little evidence of abrasion, fragmentation, or bioerosion suggesting minimal transport, reworking, and exposure on the sea floor and rapid burial resulting in a largely parautochthonous assemblage ( sensu Kidwell et al., 1986). Minor taphonomic displacement of faunal elements was apparent in loc ality outcrops and in bulk samples during processing in the form of bathymetrically di splaced taxa or faunal elements displaced from adjacent habitats. Preservation was excellent for calcitic taxa (oysters, pectinids, mussels, and some gastropods) but genera lly poor for aragonitic taxa with most shells showing effects of leaching. Collections fr om several localities consisted entirely of molds of aragonitic taxa. It could be argued th at the composition of locality collections may be biased due to differential prese rvation of thick-shelled taxa versus thin-shelled taxa. However, Behrensmeyer et al. (2 005) found that taphonomic effects are neutral with respect to durability. There was no evidence in this study of complete taphonomic loss of aragonitic taxa from locality co llections leaving only calcitic taxa nor cases where collections with similar calcitic taxa compositions lacked the expected, associated aragonitic taxa especially thin-shelled forms (e.g. Mya Macoma Modiolus Psephidia and Solen ). Differences in the placement of the base of the Etc hegoin group in previous studies were mitigated for by correlating the relat ive stratigraphic positions of all fossil localities in this study to a composite stratigraph ic column constructed for the central Kreyenhagen Hills where the most continuous Etchego in group section is exposed. The composition of each locality collection was reviewe d and updated to the current accepted taxonomy to remove synonymous species and uncertain identifications (sp., aff., ident., and “?”) as well as reworked taxa, in preparation f or statistical analysis (Chapter 1). The manner of these revisions was uniformly applied to all faunas in this study. The Etchegoin group mollusc fauna consists of 176 speci es and subspecies including 101 bivalve and 75 gastropod species and subspecies. A pproximately 35% of the Etchegoin group mollusc fauna consists of extant species and all of those are representative of shallow-water, nearshore environments (Bowersox, 20 05). A subset of data from each sample interval was compiled for species endemic to the SJB, herein defined as those extinct species without a recorded presence outside of the SJB, for the calculation of diversity indices. Endemic species comprise ~29% of the fauna (30 bivalve species and 23 gastropod species) although some of the appearan ce of endemism in the SJB fauna may be an artefact of an incomplete California Plio cene fossil record (Bowersox, 2005). In toto these faunas (Arnold, 1909; Arnold and Anderson, 1 910; Hoots, 1930; Woodring et al., 1940; Adegoke, 1969; Loomis, 1990; this stu dy) form a stratigraphically

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130 Table 5.1. Areal (Fig. 5.1) and stratigraphic distributions ( Fig. 5.2) and numbers of locality collections compiled in this study. Locat ions of Etchegoin group fossil localities (columns) are noted on Figure 1: A. White Creek Syncline, B. Coalinga Anticline, C. Priest Valley, D. Jacalitos Anticline, E. Kreyenhagen Hills, F. Kettleman Hills, G. Bacon Hills, H. Muddy Creek.

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131 Figure 5.3. Species richness and occurrences from 484 localit y collections were compiled in 126 ten-meter sample intervals. The num ber of locality collections comprising 10 m-sample intervals shoes sampling to have been heaviest in the uppermost Etchegoin (~1500-1700 m) and basal upper San Joaquin (~2100-2300 m) where the Etchegoin group is best exposed. This figure demon strates the relationship between species richness and abundance (Table 5.2A): specie s are most abundant where there are many species present (Fig. 5.4). While the number occurrences correlates well to the number of localities in a sample interval ( r2 = 0.82) species richness only weakly relates to sampling intensity (Fig. 5.4, r2 = 0.58) suggesting that it is unlikely that abunda nt taxa are over represented in the locality collections. Extinction events in the history of the SJB are noted A-H (modified from Bowersox, 2005).

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132 constrained database that includes the entire Etch egoin group fauna. Statistical Analysis The basis for the statistical analysis in this stud y are two pieces of information determined from locality collections: 1) the number of species present in a locality collection (species richness, S); and 2) the number of locality collections in a sample interval where a given species was found (occurrenc es, n ), and the total number of occurrences of all species (N). Small-scale popula tion indices, S and N were compiled from locality collections (n) in 116 ten-meter stra tigraphic sample intervals (Fig. 5.3). S and N are cross-correlated (r2 = 0.86) allowing the use of occurrences as a proxy for abundance because an ecological group with more occ urrences is likely to have been locally more abundant, had a greater geographic dis tribution, as well as a broader environmental range (Hayek and Buzas, 1997; Buzas a nd Culver, 1999; Madin et al., 2006; Fig. 5.4). Distribution of species richness and species occurrences are presented in Figure 5.5A-B. Sampling was heaviest (Fig. 5.3) in the uppermost E tchegoin (~1500-1700 m) and basal upper San Joaquin (~2100-2300 m) where the Etc hegoin group is best exposed. In order to test for bias due to greater sampling inte nsity of better exposed sections the Etchegoin group fauna was modeled after the techniq ue of Crampton et al. (2003). Outcrop areas were determined for nine stratigraphi c intervals within the marine section of the Etchegoin group exposed in the Coalinga regi on corresponding to the fauna zonules of Adegoke (1969), the smallest practical s cale for this test, from the geologic maps of Woodring et al. (1940), Adegoke (1969), Dib blee (1971), Hall and Loomis (1992), and field work of this study. The outcrop area of the Etchegoin group marine section in the Coalinga region totals ~340 km2 and ranges from a low of ~3 km2 of exposed and preserved basal Jacalitos (zonule 8 of Adegoke, 1969) on the Coalinga Anticline to a high totaling ~80 km2 of uppermost Etchegoin (zonule 12 of Adegoke, 1969; Patinopecten through Littorina zones and their correlates of Woodring et al., 194 0) exposed in the Kettleman Hills North, Middle, and S outh Domes (Fig. 5.6). Spearman's correlation coefficient matrix was calculated using the module in PAST software version 1.45 (PAlaeontological STatistics; Hammer et al., 2 001) for the outcrop area (A) of each of the nine stratigraphic intervals and the number of locality collections (n), S, and N from each interval (Table 5.2A). In contrast to th e results of Crampton et al. (2003), correlation is not significant between A and any of the three tested factors (p > 0.05) suggesting that the nature of the collections of th e Etchegoin group in toto have not introduced a bias when the data for species richnes s and other paleoecologic components are compiled. A second Spearman's correlation coefficient matrix was calculated for n, S, and N from the116 ten-meter stratigraphic sample (Table 5 .2B). Not unexpectedly, correlation exists between n, S, and N (p < 0.05). However cor relation does not demonstrate causation. N is largely explained by n (r2 = 0.82; more collections yields more occurrences of taxa) therefore suggesting that all taxa are approximately uniformly sampled at all sampling intensities. S is weakly r elated to n (r2 = 0.58) suggesting that

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133 Figure 5.4. Sampling intensity and covariance of S and N. Sp ecies richness and occurrences are cross-correlated (r2 = 0.86) which allows the use of occurrences from t he compiled binary (presence-absence) database as a pr oxy for abundance: an ecological group with more occurrences is likely to have been locally more abundant, had a greater geographic distribution, and broader environmental range (Madin et al., 2006).

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134 Figure 5.5A. Distribution of species richness of the total and endemic Etchegoin group faunas. Distribution of species richness and speci es occurrences were tested for sampling bias of the faunal composition. Species richness of both the total and endemic Etchegoin group faunas demonstrate a log-normal distribution which is characteristic of natural populations as sampling intensity increases (Hayek and Buzas, 1997).

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135 Figure 5.5B. Rank order occurrences of species comprising the total and endemic faunas. Likewise the rank order occurrences of spe cies comprising the total and endemic faunas also follow the log-normal distribution. Th ese figures also suggest that increasing sampling intensity beyond the 484 localities of thi s study would at best add a few very rare species, if any, to the fauna. Therefore the Etchegoin group mollusc fauna has been appropriately and adequately sampled. These curves are also indicative of the heterogeneity ( sensu Rousseau and van Hecke, 1999) of the endemic and t otal Etchegoin group faunas.: the steeper curve of the endemic fau na is indicative of a more homogeneous fauna than that of the total Etchegoin group.

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136 Figure 5.6. Outcrop area (A) of marine Etchegoin group stratig raphic intervals corresponding to the fauna zonule of Adegoke (1969) and the number of localities per interval (n). The test for bias due to greater sampling inten sity of better exposed sections the Etchegoin group fauna was modeled after Crampto n et al. (2003). The total outcrop area of the Etchegoin group in the Coalinga region is ~340 km2 and ranges from ~3 km2of exposed and preserved basal Jacalitos (zonule 8 of Adegoke, 1969) on the Coalinga Anticline to a high totaling ~80 km2 of uppermost Etchegoin (zonule 12 of Adegoke, 1969; Patinopecten through Littorina zones and their correlates of Woodring et al., 194 0) exposed in the Kettleman Hills North, Middle, and S outh Domes (Fig. 5.1). Spearman's correlation coefficient matrix was calculated from the data from each stratigraphic interval using the module in PAST software version 1.45 comparing A, n, S, and N from each interval (Table 5.2A). Contrary to the result s of Crampton et al. (2003) correlation cannot be proved between A and any of the three tes ted factors (p > 0.05) suggesting that the Etchegoin group in toto has been appropriately collected.

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137 Table 5.2A Spearman's correlation coefficient matrix test of outcrop area, n, N, and S. Spearman's correlation coefficient matrix was calcu lated using the module in PAST software version 1.45 (PAlaeontological STatistics; Hammer et al., 2001). Correlation was tested between the outcrop area (A) of each of the nine stratigraphic intervals and the number of locality collections (n), S, and N from e ach interval. Contrary to the results of Crampton et al. (2003) correlation cannot be proved between A and any of the three tested factors (p >0.05) suggesting that the Etcheg oin group in toto has been appropriately collected.Table 5.2B. Correlation was tested for n, S, and N from the116 ten-meter stratigraphic sample. Not unexpectedly, correlation is proved be tween n, S, and N (p <0.05). N is largely explained by n (r2 = 0.82; more collections yields more occurrences o f taxa) therefore suggesting that all taxa are approximatel y uniformly sampled at all sampling intensities. S is weakly related to n (r2 = 0.58) suggesting that abundant taxa are not overly represented in the locality collections.

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138 abundant taxa are not overly represented in the lo cality collections. This relationship is much like that investigated by Poore and Rainer (1 974) who concluded that differences in regional diversity are not related to sample siz e. The corollary to over-represented abundant taxa is the under representation of middle -rank and rare taxa. The rank abundance of species in a natural population is a l og-normal relationship (Buzas et al., 1982; Hayek and Buzas, 1997; Buzas and Culver, 1999 ). To test for under-representation species in the Etchegoin group fauna the rank occu rrences of the species from the 15 stratigraphic intervals deposited during the 4th-order eustatic cycles (Fig. 5.2) was determined (Fig. 5.7A-D). The rank occurrences of species in the lower Jacalitos fauna (Fig. 5.7A) is indicative of under-represented midd le-rank and rare species which suggests any conclusions that may be drawn from tha t portion of the fauna should be considered tentative. Five other faunas, those fro m the upper Jacalitos, upper Etchegoin A, as well as the Littorina Trachycardium and Acila zones (Fig. 5.7A-B, D), are demonstrative of the under-representation of rare s pecies although the presence or absence of only rare taxa does not have a significa nt effect on analysis of diversity (Marchant, 1999). Population indices including the Shannon informatio n function (diversity index, H; Shannon, 1948) and evenness (E; Buzas and Gibson 1969; Hayek and Buzas, 1997) were calculated from S and N (Buzas and Culver, 199 9) for the total fauna (HT), nonendemic fauna (HM), and endemic fauna (HE) from each 10 m sample interval (Fig. 5.8) using the Diversity Indices module of PAST: (1) where pi is the fraction of the occurrences of the ith species in the sample ( ni/N). The relative value of H is a sound indication of divers ity in a population in terms of the number of species and the distribution of individua ls among those species (Hayek and Buzas, 1997). E (equation 2) is an index of how in dividuals are distributed among species in a population (Hayek and Buzas, 1997) whe re a value of one indicates that all species are equally represented. Overall Etchegoin group faunal structure, the distribution of occurrences among the species, was examined by comparing HT and E to S for each sample interval (Fig. 5.9). To test the e ffects of scaling on diversity, H was calculated for the total, endemic, and non-endemic faunas from each 4th-order eustatic cycle during Etchegoin group deposition, for each o f the three formations comprising the Etchegoin group, and for the Etchegoin group in toto (Fig. 5.10). Results Species richness of samples from the Etchegoin grou p is low with five or fewer species found in 67% of locality collections (Fig. 5.5A) and 21% of species comprising the fauna accounting for 67% of all occurrences (Fi g. 5.5B). Despite the low diversity, the flattening of the curves at higher cumulative p ercentages suggests that the fauna has

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139 Figure 5.7. Test for under-representation of species in Etche goin group faunas. Underrepresentation species in the Etchegoin group fauna was tested by ranking the occurrences the species from the 15 stratigraphic intervals dep osited during the 4th order eustatic cycles (Fig. 5.2). The rank abundance of species i n the lower Jacalitos fauna (A) is indicative of under-represented middle-rank and rar e species which mitigates any conclusions that may be drawn from statistical anal ysis of the fauna. Five faunas (upper Jacalitos, upper Etchegoin A, Littorina zone, Trachycardium zone, and Acila zone; A-B, D) are demonstrative of the under-representation of rare species although the presence or absence of rare taxa does not have a significant ef fect on diversity analysis (Marchant, 1999). Faunas from the balance of the intervals ha ve been adequately sampled.

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140 Figure 5.8. Comparison of Shannon diversity for the total fau na diversity (HT) and the proportional contributions to HT of the non-endemic (HM) and endemic (HE) faunas and total-fauna evenness (E). HE is shown as the shaded area between the HT and HM curves. On average HE accounts for 42% of HT. High H and low E correspond to periods of rapid invasion and colonization by non-endemic species an d diversification within the endemic fauna coincident with equitable environmental condi tions during eustatic transgression (Fig. 5.2). Extinctions are noted A-H.

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141 Figure 5.9. Comparison of HT and E to S tests how the occurrences of species ar e distributed among the species and the overall struc ture of the Etchegoin group fauna. HTdisplays a log-normal relationship (r2 = 0.99) characteristic of natural populations (Hay ek and Buzas, 1997) while E displays a surprisingly we ak inverse relationship to increasing S (r2 = 0.54) despite the appearance of a good correlati on.

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142 been adequately sampled. In the Etchegoin group f auna, 21 species (12% of all species) are found occurring at a single locality and additi onal sampling would likely only increase the number of rare species recognized in the fauna. The endemic fauna consists of a total of 53 species and subspecies including 30 bivalve a nd 22 gastropod species and subspecies with HE accounting for an average 42% of HT (Fig. 5.8). Five or fewer endemic species are found in 98% of locality collec tions (Fig. 5.5A) and 23% of species comprising the endemic fauna account for 67% of all endemic occurrences (Fig. 5.5B) with Pseudocardium densatum alone comprising 22% off all endemic occurrences. In the endemic fauna, 10 species (19% of endemic species) occur at only a single locality. Figure 5.8 compares total-fauna (HT) and the proportional contributions to HT of the nonendemic (HM) and endemic (HE) faunas and total-fauna evenness (E). E appears t o mirror HT suggesting that greater diversity derives from man y low-abundance and rare species added to faunas otherwise dominated by a few very a bundant species (Fig. 5.8). Figure 5.9 plots HT and E as functions of S. HT displays a displays a strong correlation to S (r = 0.845, p <0.001) and direct log-normal relationship (r2 = 0.99) whereas E displays a strong inverse correlation (r = -0.735, p < 0.001) to increasing S. Figures 5.10-5.11 demonstrate partitioning HT as the scale of faunal diversity coarsens from the 10 m sample interval (2 diversity, Fig. 5.10) and individual locality coll ection (1 diversity, Fig. 5.11) to that of the entire 2430 m ( diversity) interval of the Etchegoin group. Discussion Inspection of the stratigraphic plots of HT and E in Figure 5.6 shows the expected correspondence of the population indices to the dis tribution of S and N (Fig. 5.3). This distribution of S and N is characteristic of faunas with a few abundant species and many rare species. That is, in a large data set abundan t species occur most frequently (Hayek and Buzas, 1997; Buzas and Culver, 1999) and S incr eases with the number of observations made (Buzas and Hayek, 2005). Because the diversity varies with changes in S and N, the 10 m-compiled locality collections are indicative of between-community sampling where the sample set is drawn from tempora lly-adjacent communities with different statistical distributions and/or the same distribution with differing parametric values (Buzas and Hayek, 2005). The stratigraphic distributions of the diversity indices (Fig. 5.8) are indicative of two qualities of the d ata compilation: the 10-meter compiled sample intervals may include one or more locality c ollections from one or more stratigraphic levels within the compiled interval. Therefore, multiple communities may be represented in a compiled sample interval. E mi rrors HT because of its derivation from H and S: E = eH/S(2) and H = ln S + ln E(3)

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143 which requires that as the number of species increa ses ( ln S), evenness ( ln E) must decrease (Buzas and Culver, 1999; the correlation i n this dataset between S, H, and E is significant at p <0.0001). That is, as either H or E is fixed the other will vary with S (Buzas and Culver, 1999). Because H is sensitive to the amount of rare specie s in a fauna (Etter, 1999), diversity increase and corresponding evenness decre ase during deposition of the upper lower Etchegoin, uppermost Etchegoin, and upper San Joaquin (Fig. 8) is due to the addition of lower rank-status, less abundant to sin gle occurrence species to the faunas (Fig. 5.7A-D). That is, 19% of species account for 67% of all occurrences in the Etchegoin group as a whole with a range of 15-33% o f species accounting for 67% of all occurrences in the individual members (Fig. 5.12A). On average, uncommon species account for ~23% of the HT. However, there is only a moderate correlation be tween the proportion of abundant species in the fauna from ea ch Etchegoin group member and HTand E (r = 0.64 in both cases, p <0.08; Fig. 5.12B) but a very strong relationship between the proportion of abundant species and E (r = 0.91, p <0.006). This stems from the nature of generalist species to occur in most habitats and maintain high population densities whereas more stenotopic species are restricted to a single habitat type at low population densities (Kitahara and Fujii, 1994; Wagner et al., 2000). Temporal and Spatial Scaling of Diversity Diversity may be additively partitioned within and among habitats (Allan, 1975) and compared across spatial and temporal sampling s cales (Gering et al., 2003). Total diversity (), defined in temporal or spatial terms, may be par titioned into average diversity within samples () and among samples () to estimate diversity from = – (Wagner et al., 2000). In this study, diversity is temporally partitioned into locality collections (1) and 10 m-sample intervals (2; HT, above) for the comparison of trends in diversity in the Pliocene SJB (Fig.5.11). Figure 5 .11 scales total Etchegoin group faunal diversity from 1 and 2 through 1 ( 4th-order eustatic cycle), 2 (formation), to diversity (Etchegoin group in toto at the sample interval level). Calculation of H is dependent upon S and N, both of which increase as t he scale of the sample interval increases due to the inclusion of more locality col lections. At each scale change towards a more inclusive (or larger) grouping, occurrences an d the possible number of species in the sample increases. Thus, there is a direct cross-sc ale correlation (r2 = 0.94) of average diversity as the scale increases from individual lo cality collections (1 diversity) to the Etchegoin group in toto ( diversity; Fig. 5.10-5.11). That is, higher scale diversity reflects the combined effects of heterogeneity at l ower levels (Wagner et al., 2000). Most of the diversity is explained by variations between local ity collections. All but four locality collections are from the ~400 km2 sampling region extending from the Coalinga anticline to the Kettleman Hills on the east and Kr eyenhagen Hills on the west. Thus, the 10 m-sample intervals may include a heterogeneous r epresentation of the habitats present during deposition of the section. Therefore, the c ontribution of 1 to 2, accounting for 62% of 2 diversity, is a reflection of habitat patchiness in the region. Scaling upward to the level of 4th-order eustatic

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144 Figure 5.10. The effects of temporal scaling on diversity was t ested by calculating H for coarser scale above the sample interval level (dott ed line): the 4th-order eustatic cycles occurring during Etchegoin group deposition (short dashes), the three formations comprising the Etchegoin group (long dashes), and f or the regional Etchegoin group stratigraphic interval in toto (solid line). Contributions to the total diversity () is noted at each level (Fig. 5.9). 1 diversity ( 4th-order eustatic cycles) accounts for ~80% of the total diversity and 38% of the diversity (Fig. 5.9). Extinctions are noted A-H. Faunal diversification and extinction are linked to 4th order eustatic changes (Fig. 5.2) through environmental changes associated with transgression and regression.

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145 Figure 5.11. Total Etchegoin group faunal diversity is scaled from 1 (locality collection) to diversity (Etchegoin group in toto ). H is dependent upon S and N, both of which increase as the scale of the sample interval increases as more locality collections are added. At each scaling level occurrences and t he possible number of species in the sample increases. Therefore there is a cross-scale correlation (r2 = 0.94) of average diversity to scale increase from 1 diversity to diversity (Fig. 5.8).

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146 Figure 5.12A. Composition of the Etchegoin group fauna comprisi ng 67% of occurrences. In general 67% of the faunal occurren ces includes the major species characteristic of a faunas composition. In the Etc hegoin group fauna 19% of species account for 67% of all occurrences with a range of 15-33% of species accounting for 67% of all occurrences in faunas from the individual st ratigraphic members. On average, uncommon species account for ~23% of the total Etch egoin group diversity.

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147 Figure 5.12B. Total fauna diversity compared to the proportion o f the fauna comprising 67% of occurrences. There correlation is weak (r2 = 0.42) between the proportion of abundant species and HT in the faunas from the stratigraphic members of th e Etchegoin group.

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148 variations demonstrates that 1 accounts for ~80% of the total diversity consistent with the eustatic control of Etchegoin group faunal comp osition reported by Bowersox (2005). Eustatic changes during the Pliocene in the SJB und erlie the cyclic sedimentation and faunal changes in the Etchegoin group observed by S tanton and Dodd (1972), particularly those identified in the uppermost Etchegoin and upp er San Joaquin formations (Fig. 5.2). Further raising scaling to the level of formation, coincident with 3rd-order eustatic highstand and regression at formation boundaries an d subsequent transgressive basin flooding, shows 2 comprising the ~20% balance of the diversity evident in the Etchegoin group faunal composition. Exploration of spatial scaling of diversity within the Etchegoin group is shown in Figure 5.13. Diversity is spatially scaled into l ocality collections (), sample clusters (1), sample areas (2), and total regional faunal diversity (). A single 10 m-sample interval from the transgressive section at the base of the Siphonalia zone (Fig. 5.2) was chosen due to its broad regional distribution of locality collections Average diversity was determined at the scale of the locality collect ion (), clusters of nearby to adjacent localities (sample clusters, 1), each area (i.e., Coalinga Anticline, Jacalitos A nticline, Kreyenhagen Hills, and Kettleman Hills; 2), and the Coalinga region (). Excluding the single locality collection from the Kreyenhagen Hil ls, diversity of the Coalinga Anticline, Jacalitos Anticline, and Kettleman Hills is comparable and relatively low. However, although average S of the individual local ity collections from these three areas only ranges from 5-7, average E is 0.83 in Kettlema n Hills locality collections, 0.73 in the Coalinga Anticline collections, and 0.67 in the Jac alitos Anticline collections. This variation in E between areas is explained by the Ja calitos Anticline fauna being characteristic of the a tidal-flat habitat where si x bivalve species (30% of the fauna) comprise 67% of occurrences whereas in the combined more species-rich and diverse Coalinga Anticline and Kettleman Hills faunas, char acteristic of the Pecten-Chione community and indicative of normal-marine condition s (Chapter 4), 67% of the fauna is comprised of 42% of species. Raising scaling to the levels of 1 and 2 diversity, ~40% of diversity in the Coalinga Anticline and Kettleman Hills areas is explained at 1, diversity between clusters of adjacent locality col lections, and ~60% as 2 diversity, among the locality clusters (1 level) in an area, suggesting a distributional con trol on the faunas from habitat patchiness. Approximately 80% of the Jacalitos Anticline fauna’s diversity is between localities (1 level) suggesting strong control of faunal distrib ution due to habitat patchiness on the tidal flat. In mo dern, nearshore marine environments, patchiness due to the distribution of substrate typ es has been documented most often as the primary environmental control on the spatial di stribution of modern intertidal and nearshore molluscs (Packard, 1918a; Stanton and Dod d, 1970; Tunberg, 1981; Brenchley, 1982; Wignall, 1993; Cattaneo-Vietti et al., 2000; Teske and Woolridge, 2003; Denadai et al., 2005; Lourido et al., 2006) and also plays a major role in the SJB (see Chapter 4). Scaling Endemic Fauna Diversity The contribution of endemic species to total divers ity varies from 23-44% of diversity depending upon the scaling level (Fig. 5. 14). At the scale of locality collections,

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149 Figure 5.13. Regional diversity distributions from a single 10 m-sample interval from the transgressive section at the base of the Siphonalia zone. Average diversity was determined at the scale of the locality collection (), clusters of nearby to adjacent localities (1), each area (Coalinga Anticline, Jacalitos Anticli ne, and Kettleman Hills;2), and the study region (). The Jacalitos Anticline fauna is characteristic of a tidal-flat habitat where six bivalve species dominate the faun a whereas the larger and more diverse Coalinga Anticline and Kettleman Hills faunas are c haracteristic of the PatinopectenMacoma community (Chapter 4; outer bay community of Stanton and Dodd, 1970). Approximately 40% of diversity in the Coalinga Anticline and Kettleman Hills areas is explained between locality collections while about 80% of the diversity of Jacalitos Anticline fauna is between locality collections sug gesting strong substrate control of habitat patchiness on the tidal flat.

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150 HE is 23% of 1 diversity and ~20% less than the 29% contribution o f endemic species richness (SE, 53 species) to total Etchegoin group species rich ness (ST, 180 species):1E /(1E + 1M) < SE/ST(4) where 1E is the 1 diversity of the endemic fauna and 1M is the 1 diversity of the nonendemic fauna and SE/ST is the fraction of the total fauna composed of end emic species. In modern faunas, the 1 diversity component, the diversity of the fauna at any site on the landscape, is determined by within-community proces ses (competition and predation; Shmida and Wilson, 1985) although in the fossil rec ord evidence of short-term community dynamics is unlikely to be preserved due to time averaging (Brett, 1998). At the scale of locality collections from the Etchegoi n group, 1 diversity is comparable to the within-community diversity as determined by hab itat patchiness observed in modern associations (Shmida and Wilson, 1985) where genera list species, those species with broad environmental requirements, will be most wide ly distributed and abundant (Kitahara and Fujii, 1994; Wagner et al., 2000) and thus, the greater contributor to 1diversity. The endemic fauna may have narrower spa tial distributions in the range between generalist and specialist species, species adapted to a more limited environmental range and consequent habitats, and th us contribute proportionally less to alpha diversity than its relative contribution to t he faunal composition overall. The 10 msample intervals, the level of 2 diversity, are compiled from an average of three l ocality collections (Fig. 5.3) and at this diversity level, HE comprises 30% of 2 diversity and thus approximates SE/ST:2E /(2E + 2M) SE/ST(5) where 2E is the2 diversity of the endemic fauna and 2M is the 2 diversity of the nonendemic fauna. The 10 m-sample intervals average t he habitat variations between individual locality collections, between endemic an d non-endemic species, between generalist and specialist species, both spatially a nd temporally, within both the endemic and non-endemic faunas. Overor under-sampling an element may add chaotic artefacts to the dataset and thus making the possibility of a ccurate inferences about the behavior of the system through time problematical. The sample size, the area and/or stratigraphic interval being sampled, should not contribute to ov eror under-sampling any particular faunal element and represent an average of the faun al structure to avoid creating diversity artefacts. Here, the faunal element investigated was the endemic portion of the Etchegoin group fauna versus the non-endemic portio n of the fauna, although this test could be applied to any other division of a fauna, including: bivalves versus gastropods, guild structure, predators versus prey, environment al tolerances, and dispersal modes. With variations smoothed between individual localit y collections, the compiled faunal structure reflects the Etchegoin group fauna in toto and thus the strong correlation of S and H (Figure 5.9, Table 5.2B) requires that the pr oportion of 2E diversity approximate SE/ST. This suggests that compiled 10 m-sample interval s are appropriate for the

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151 Figure 5.14. Contribution of the endemic fauna to Etchegoin gr oup diversity with increasing sample scale. The endemic fauna account s for 42% of the Etchegoin group diversity but varies with the scaling level from 23 -44% of diversity. At the level of 1diversity the spatial distributions of organisms ar e determined by within-community processes (Shmida and Wilson, 1985) and habitat pat chiness as observed in modern associations (Shmida and Wilson, 1985) where genera list species will be most widely distributed and abundant (Kitahara and Fujii, 1994; Wagner et al., 2000) and thus the greater contributor to 1 diversity. Diversity at the 10 m-sample intervals level HEcomprises 30% of 2diversity. The 10 m-sample intervals average the h abitat variations between locality collections, between endemic and n on-endemic species, and between generalist and specialist species within both the e ndemic and non-endemic faunas. The greatest change in the proportion HE contributes to diversity comes when the temporal scale is increased from the 10 m-sample interval to the 4th order eustatic cycle (1diversity). At this step the endemic fauna compris es 37% of the 1 diversity an increase of ~34% over 2 at the level of the 10 m-sample interval. Increm ental diversity is greatest between 4th order eustatic cycles because this is where enviro nmental variability was greatest. Basin flooding during transgression brought invasion and colonization by non-endemic coastal species and provided a drive fo r diversification of the endemic fauna while environmental deterioration during regression led to extinction. Scaling up to the level of formations (2 diversity), coincident with 3rd order eustatic cycles, increases diversity by an additional ~17% and then ~2.5% when s caled to diversity of the Etchegoin group in toto At these scaling levels 2 diversity is due to extinctions associated with eustatic regression at formations b oundaries (Fig. 5.2).

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152 statistical analysis of the Etchegoin group fauna. The greatest change in the proportion of diversity contributed by endemic species is demonstrated when the temporal scale is increase d from the 10 m-sample interval to the 4th-order eustatic cycle (1). At this step, the endemic fauna comprises 37% o f the 1diversity an increase of ~34% over 2 at the level of the 10 m-sample interval:1E /(1E + 1M) > SE/ST(6) where 1E is the 1 diversity of the endemic fauna and 1M is the 1 diversity of the nonendemic fauna. Incremental diversity, the increase in diversity as the scale increases, is greatest at the scale of 1 diversity, 4th-order eustatic cycles, because environmental variability was greatest. Basin flooding during tr ansgression brought invasion and colonization by non-endemic coastal species and pro vided a drive for diversification of the endemic fauna. Environmental deterioration dur ing regression led to the extinction of endemic species and possible extinction of stenotop ic species as their preferred habitats disappeared from the SJB and they were subsequently forced to live in what may have become marginal environments for them (Valentine an d Jablonski, 1991). Thus, abrupt regression-driven hydrologic change, productivity c ollapse from coincident geochemical and sedimentary change, and climatic change led to the major extinction events in the Pliocene SJB (see Chapter 6). Alexander et al. (1993) found that in non-endemic f aunas from the uppermost Etchegoin and San Joaquin formations in the Kettlem an Hills habitat-generalist bivalve species Anadara trilineata Mya arenaria, and the intermediate species (neither generalist nor specialist) Macoma nasuta were found in 12-13 of 20 successive biostratigrap hic intervals corresponding to SJB 4th-order eustatic cycles ( Patinopecten through upper Mya zones, Stanton and Dodd, 1970, 1972), whereas the s pecialist species Mactromeris sp and Acila castrensis were never found in more than four. Occurrences o f the generalist and intermediate species peaks when HT is low suggests that these species adapted to and exploited the habitat variations arising from eusta tic changes in the SJB, whereas specialist members of the fauna suffered reduced ab undance and extinction (Fig.5.15A). A similar pattern of abundances can be demonstrated in the extinct endemic bivalve fauna (Fig. 5.15B). Pseudocardium densatum appears to be a generalist species with abundance peaking during periods of low faunal diversity, Macoma affinis ssp.(temporal distribution comparable to extant species Macoma nasuta Fig. 5.15A) and Protothaca stayeli hannibali appear to be intermediate species, and Oppenheimopecten coalingensis appears as a specialist species whose range coincides with periods of peak faunal diversity when environmental conditions were most equitable. Scaling up to the level of formations (2), coincident with 3rd-order eustatic cycles, increases diversity by an additional ~17% and then ~2 .5% when scaled to diversity of the Etchegoin group in toto At these scaling levels, 2 diversity is due to extinctions associated with eustatic regression at formations b oundaries: at the JacalitosEtchegoin(Bowersox, 2005), Etchegoin-San Joaquin, a nd San Joaquin-Tulare boundaries (Fig. 5.3, 5.8, extinctions C, H). The most extens ive extinction was at the Etchegoin-San

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153 Figure 5.15A. Comparison of the temporal distributions of some g eneralist and specialist species in the Etchegoin group fauna as their percent of occurrences of the total fauna. Diversity curves are shown for reference. O pen circles are occurrences in single, non-contiguous sample intervals. In non-endemic fa unas from the uppermost Etchegoin and San Joaquin in the Kettleman Hills habitat-gene ralist bivalve species Anadara trilineata Mya arenaria, and intermediate species Macoma nasuta were found in 12-13 of 20 successive biostratigraphic intervals corresp onding to SJB 4th order eustatic cycles ( Patinopecten through upper Mya zones, Stanton and Dodd, 1970, 1972) while special ist species Mactromeris sp and Acila castrensis were never found in more than four (Alexander et al., 1993). All species shown other than Anadara trilineata first appeared in the SJB during basal Jacalitos basin flooding. Occurrences of the generalist and intermediate species peaks when HT is low suggesting that these species adapted to an d exploited the habitat variations arising from eusta tic changes in the SJB while specialist members of the fauna suffered reduced abundance and extinction.

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154 Figure 5.15B. Comparison of the temporal distributions of some g eneralist and specialist species in the endemic Etchegoin group fauna. A sim ilar pattern of abundances can be demonstrated in the extinct endemic bivalve fauna w here Pseudocardium densatum appears to be a generalist species (abundance peaki ng during periods of low faunal diversity), Macoma affinis ssp.(temporal distribution comparable to the extan t species Macoma nasuta ) and Protothaca stayeli hannibali appear to be an intermediate species, and Oppenheimopecten coalingensis appears as a specialist species whose range coincides with periods of peak faunal diversity whe n environmental conditions were most equitable. Only Pseudocardium densatum was present at the beginning of Etchegoin group deposition.

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155 Joaquin boundary accounting for ~75% loss in species richness and diversity of both the endemic and non-endemic faunas from their peaks dur ing middle Siphonalia zone deposition (Fig. 5.2, 5.3). Evenness increased dur ing this period coincident with the reduction in species richness and diversity (Fig. 5 .8; equation 3). The small increase in diversity from 2 to is indicative of endemic species ranging through f ormations with few species limited to single formations.Eustatic Control of Diversity Correlation of sea-level change as a primary drive of extinction has long been recognized in the fossil record (e.g., Hallam, 1989 ). In the Pliocene SJB, 4th-order eustatic variation forcing paleooceanographic chang es was the dominant mechanism acting on the structure of the marine molluscan fau na (Bowersox, 2005; Figs. 5.2, 5.3, 5.8). Species richness and diversity in the Plioce ne SJB was greatest during periods of basin flooding at eustatic highstand then declined with regression to the extinction events at eustatic lowstand (Bowersox, 2005; Fig. 5.3, 5.8 ). Comparison of S and N (Fig. 5.3) and HT, HE, and E (Fig. 5.8) reveals the subtle dynamics of co mmunity and faunal response to environmental change in the Pliocene SJ B. Diversity rose with marine transgression and fell when the water became cooler and brackish during eustatic regression (Fig. 5.16A). Peak values of S and N (F ig. 5.3) and thus HT and HE (Fig. 5.16A) are coincident with the earliest Pliocene eu static transgression during deposition of the basal 50 m of the Jacalitos (Fig. 5.2, 5.3-5 .1 Ma) then display an overall decline in concert with environmental deterioration and increa sed habitat heterogeneity proceeding eustatic lowstand marking the end of Jacalitos depo sition at 4.8 Ma (Fig. 5.2). However, the timing of the earliest Pliocene extinction is u ncertain except that it occurred during deposition of the lower Jacalitos above the 50 m an d below the 219 m stratigraphic levels (Fig. 5.16A, extinction A). Fossil-bearing sedimen ts deposited during the earliest Pliocene transgression are only exposed and preserv ed in a small area on the Coalinga Anticline and in the stratigraphically lowest secti on of the lower Jacalitos in the White Creek Syncline west of Coalinga (Fig. 5.1). The ov erlying lower Jacalitos section is unfossiliferous on the Coalinga Anticline through d eposition of the lower Etchegoin Formation and the Kreyenhagen Hills section of the lower Jacalitos is non-marine. Increasing HT and HE with decreasing E values during deposition of the lower Etchegoin Formation (4.8-4.4 Ma, Fig. 5.8) reflects community diversification and addition of low abundance species thus increasing S (equation 3) as the environment returned to normal-marine conditions. Following th e extinction coincident with eustatic lowstand at the end of lower Etchegoin Formation de position (Fig. 5.3, 5.10, 5.16A, extinction B) S (Fig. 5.3), HT, and HE (Fig. 5.16A) gradually increased through depositio n of the upper Etchegoin Formation reaching their pea k in the Siphonalia zone of the uppermost Etchegoin (Fig. 5.6, ~4.1 Ma; Fig. 5.16A) at maximum early Pliocene basin flooding. HT and HE each decreased by half (Fig. 5.16A) in concert and reflective of marine environmental deterioration during depositio n of the uppermost Etchegoin and basal San Joaquin formations (~4.1-3.9 Ma, Fig. 5.16 A; Bowersox, 2005) leading to the extinctions (effectively reducing S) at the end of Etchegoin deposition (Fig. 5.6, 5.16A,

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156 Figure 5.16A. Total and endemic fauna diversity compared to 4th order eustatic sea level and generalized paleotemperature and paleosalinity (modified from Bowersox, 2005). Diversity rose with marine transgression and fell w hen the water became cooler and brackish during eustatic regression. HT and HE apparently coincide with paleotemperature and paleosalinity however the correlation of divers ity to these environmental parameters is uncertain pending accurate determinations of the ir magnitudes. Rapid fall of endemicfauna diversity prior to extinction events A-H demo nstrates the environmental sensitivity of the stenotopic Etchegoin group endemic fauna cau sing it to be extinction-prone. Diversity of the non-endemic portion of the Etchego in group fauna was less variable and generally peaked at approximately the same value in dicating the limit of available niche filling by immigrant species.

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157 Figure 5.16B. HT can be partitioned between the endemic and non-end emic contributions to demonstrate habitat exploitation. Cumulative diversity curves HT-HE(non-endemic diversity) and HT indicate by the difference between the curves (sha ded, HE) shows that with equitable environmental condition s endemic diversity rapidly increases. This suggests rapid diversification of the stenotopic endemic fauna into the portion of the SJB habitat otherwise unavailable to the non-endemic fauna.

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158 extinction C) and at the end of deposition of the b asal San Joaquin Cascajo Conglomerate (Fig. 5.6, 5.16A, extinction D). Sparse, less-dive rse, brackish-water faunas from the lower San Joaquin (Fig. 5.6, 5.16A) are characteriz ed by a greater value of E (Fig. 5.8) where a few abundant species comprise most of the f aunas. Four cycles of basin flooding with brief periods of near-normal marine conditions after 3.1 Ma supported range expansion and colonization of Pacific coastal speci es into the SJB (Stanton and Dodd, 1997; Bowersox, 2005). Rapid diversification of th is fauna is reflected in the sharp drop in E during deposition of the basal Pecten zone correspond to an increase of HT and HE to values comparable to those during deposition of the uppermost Etchegoin. Rapid diversification of the Pecten zone fauna at ~3.1-3.0 Ma (Stanton and Dodd, 1997; Bowersox, 2005; Fig. 5.8) is reflected in the lowes t value for E in any Etchegoin group fauna where many species were rapidly added to the fauna. Extinctions coincident with four short periods of eustatic regression and assoc iated brackish-water conditions sharply reduced diversity (~2.8, 2.6, 2.4, and 2.35 Ma, Fig. 5.3, 5.10, 5.16A, extinctions E-G). Rapid diversification of the small fauna present in the SJB at the time of the final marine transgression just prior to2.2 Ma is demonstrated i n the diversity spike (Fig. 5.3, 5.10, 5.16A) immediately prior to the final closure of th e Priest Valley Strait cutting the connection to the ocean and leading to the extincti on of the Pliocene marine fauna in the SJB (Fig. 5.3, 5.10, 5.16A, extinction H). Comparison of SJB and Central Coastal California Pl iocene and Modern Faunas Figure 5.17 compares diversity of the Etchegoin group to diversity calculated for the Pliocene faunas from the Santa Maria Basin (SMB, Woodring and Bramlette, 1950; Fig. 5.17A) and modern central coastal Califo rnia estuarine faunas (Fig. 5.17B) using the methods of this study: San Francisco Bay (Packard, 1918b), Elkhorn Slough (MacGinitie, 1935), and Mugu Lagoon (Warme, 1971). The Pliocene SMB fauna is comparable to the SJB fauna in terms of its tempora l distribution and provides a comparison of a fauna exposed to the open ocean ver sus that from the marginal ocean basin Pliocene SJB. In general, diversity of the SM B fauna increased through the Pliocene (Fig. 5.17A) whereas diversity of the SJB fauna peaked during deposition of the Jacalitos, fell by ~25% after the extinction at 4 Ma during lower San Joaquin deposition due to the loss of endemic species, and recovered m ost of the lost diversity during upper San Joaquin deposition (Fig. 5.16A, 5.17A). During the early Pliocene, the Etchegoin Formation was deposited on the margin of a warm, shallow, mar ginal ocean basin whereas the Tinaquaic Sand of the SMB was deposited on the margin of a cooler, deeper water basin open to the Pacific. The composition o f the Tinaquaic Sand fauna (Woodring and Bramlette, 1950) is characteristic of a tidal f lat environment with diversity (H = 2.67; Fig. 5.17A) comparable to the 2 diversity of the basal Siphonalia zone tidal flat fauna (H = 2.83, Fig. 5.12) and suggestive of a sim ilar patchy, substrate-controlled faunal distribution. Higher diversity of the Etchegoin fa una (H = 4.12; Fig. 5.17A) is indicative of the environmental breadth that the composite fau na is drawn from. By the middle Pliocene, during deposition of the lower San Joaqui n in the SJB and Foxen Mudstone in the SMB, the circulation between the SJB and Pacifi c was restricted and the marginal

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159 Figure 5.17A. Comparison of Etchegoin group diversity to diversity calculated for the Pliocene fauna from the Santa Maria Basin. Com parison of Etchegoin group diversity to diversity calculated for the Pliocene fauna from t he Santa Maria Basin (SMB, Woodring and Bramlette, 1950; A) and modern c entral coastal California estuarine faunas (B): San Francisco Bay (Packard, 1 918b), Elkhorn Slough (MacGinitie, 1935), and Mugu Lagoon (Warme, 1971). A. Early Pliocene faunas are the Etchegoin Formation of the SJB and Tinaquaic Sand of the SMB, middle Pliocene faunas are the lower San Joaquin Formation of the SJB and the Foxe n Mudstone of the SMB, and late Pliocene faunas are the upper San Joaquin Formation and Careaga Formation of the SMB. Diversity was greater in the early Pliocene S JB where the Etchegoin Formation was deposited in warm, nearshore waters of the SJB marginal ocean basin. In contrast, the Tinaquaic Sand was deposited on the shoreline m argin of the cold, deep water of the open-ocean SMB.

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160 Figure 5.17B. Diversity of modern central coastal California es tuarine faunas. Diversity of modern central coastal California estuarine faun as from San Francisco Bay (Packard, 1918b), Elkhorn Slough(MacGinitie, 1935), and Mugu Lagoon (Warme, 1971) averages 16% lower than the Etchegoin group fauna although t here is small variation in diversity between the three modern faunas. The considerably larger area and more nearly normalmarine conditions that occur in portions of San Fra ncisco Bay supports a larger though less diverse fauna than either of the generally bra ckish Elkhorn Slough and Mugu Lagoon estuaries.

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161 ocean basin was brackish (Fig. 5.16A). This bracki sh environment in the SJB supported a patchy distribution of smaller and less diverse f auna composed of a few abundant species (H = 3.10; Fig. 5.17A) when compared to the nearshore environments of the open-ocean SMB (H = 3.81; Fig. 5.17A). Peak divers ity in the SMB was reached in the late Pliocene during deposition of the Careaga Form ation (H = 3.93; Fig. 5.17A). By this time, during upper San Joaquin deposition, environm ental variability within the SJB strongly controlled composition of the upper San Jo aquin fauna (Bowersox, 2005; Fig. 5.2, 5.16A) with consequent diversity ~20% less ( H = 3.54) than the open-ocean Careaga fauna despite a broad representation of the sampled environments (Dodd and Stanton, 1975). Diversity of modern central coastal California estu arine faunas (Fig. 5.17B) averages 16% lower than the total Etchegoin group f auna (S = 171, H = 4.42) although there is small variation in diversity between the t hree modern faunas (s = 0.04): San Francisco Bay fauna (H = 3.68), Elkhorn Slough faun a (S = 57, H = 3.78), and Mugu Lagoon fauna (S = 56, H = 3.73). The considerably larger area and more nearly normalmarine conditions that occur in portions of San Fra ncisco Bay supports a more species rich (S = 93) though less diverse (H = 3.68) fauna than either of the generally brackish Elkhorn Slough and Mugu Lagoon estuaries. The lowe r value of evenness of the San Francisco Bay (E = 0.43) fauna is again indicative of a fauna where many rare species are present. By strict comparison, however, the greate r species richness and diversity of the Etchegoin group fauna stems from time averaging cau sing the accumulation of rare species in the fauna (Fig. 5.5A). By itself, the s maller San Joaquin fauna (S = 56, H= 3.56, E = 0.63) more nearly resembles the structure of the Elkhorn Slough and Mugu Lagoon faunas though with proportionally more rare species, due again to time averaging, as evidenced by the lower evenness of the San Joaqu in fauna. Applicability of Diversity Indices It could be argued that the methods of this studied predetermined its results through the relationship between S, H, and E and th e underlying lognormal model of species-abundance distributions (equations 2-3; Buz as and Culver 1999). Williamson and Gaston (2005) disputed the appropriateness of t he lognormal model in any application and presented empirical data supporting their arguments. They presented three cases of natural populations of birds, trees, and butterflies where in the first two cases the species-abundance distributions did not s trictly fit a lognormal relationship. In this study the steep slope of the rank-species rich ness curve of the lower Jacalitos Formation (Fig. 5.7A) could be interpreted as a fau na under excessive environmental stress (see the discussion in Wilsey and Polley, 20 04, and sources cited therein) however this is due to 1.) the small outcrop area of preser ved and exposed section that includes only the species-rich relatively-offshore biofacies and 2.) few samples from this interval (Fig. 5.6). Williamson and Gaston (2005) attributed the appearance of lognormal speciesabundance distributions to studies clouded by the u se of incomplete datasets and to three apparent deficiencies of the lognormal model: 1.) e mpirical fits of complete datasets were deficient in very abundant species, 2.) that the lo gnormal relationship may not apply

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162 uniformly to all populations, and 3.) the implicati on of a lognormal species-abundance distribution is that there are many abundant specie s that do not appear in samples. However, three empirical cases do not prove a rule and there is ample evidence of the applicability of the lognormal model as describing species-abundance distributions (see the discussions in Hayek and Buzas, 1997). Evenness is an index of how individuals are distrib uted among species in a population (Hayek and Buzas, 1997). There are man y methods of calculating evenness and this study followed the method outlined in Haye k and Buzas (1997). Wilson et al. (1999) studied the effect of spatial scale on evenn ess using biomass data of six sites from the literature. They employed four different indic es of evenness not including the metric of this study. Evenness decreased as spatial scale increased which was attributed to a general feature of plant species abundance distribu tions (Wilson et al., 1999) overlooking the fact that with any evenness metric increasing s pecies richness, which is concomitant with increasing spatial scale, will cause evenness to decrease. Cotgreave and Harvey (1994) studied evenness of abundances in 90 bird co mmunities from the literature using three different indices, none in common with Wilson et al. (1999) or this study, and found that evenness is high when different species have s imilar abundances which is a defining term of the model. Evenness was found to vary with habitat type and the number of species (Cotgreave and Harvey, 1994) which is a ref lection of habitat heterogeneity. Therriault (2002) employed the metrics S, H, and E used in this study but based on abundances of taxa (species abundance n and total abundance N) to examine the temporal patterns of abundance, diversity, and evenness in c oastal invertebrate communities from fresh and brackish waters in Jamaica. He demonstra ted a strong inverse correspondence between N and E, and more moderate correspondence b etween S and E, comparable to that demonstrated in this study using binary (prese nce-absence) data (Table 5.2B) and corroborating the methods herein.Implications for Ancient and Modern Marginal Ocean Basins Diversity of fossil faunas may be scaled and partit ioned both spatially (Layou, 2005; Patzkowsky, 2005) and temporally (this study, Fig. 5.16A). Figure 18 relates spatial and temporal scaling for the Etchegoin grou p fauna. Below the level of diversity of the Coalinga region, spatial diversity is distri buted from 1 to 2 diversity in approximately equal increments:1 2–1 1–2 2–1(6) ( Fig. 5.18) thus no single determinant of diversit y, either physical or biological, predominantly controlled the spatial faunal structu re. That is, the correspondence of the incremental spatial diversity reflects different co ntrols at different levels: 1.) 1 diversity, determined by spatial heterogeneity in a fauna due to habitat patchiness and withincommunity processes (competition and predation; Shm ida and Wilson, 1985); 2.) 2diversity, determined by processes of habitat varia tion (predominantly substrate and water depth, Chapter 4), to 3.) 1 diversity, determined by environmental change due to eustatic

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163 Figure 5.18. The relationship between spatial and temporal scal ing for the Etchegoin group fauna. Locality collection-level 1 diversity is shown schematically (shaded) to illustrate variations within the 10 m-sample interv al in the basal Siphonalia zone. Spatial diversity in the Coalinga region below the level of diversity is distributed from 1(shaded) to 2 diversity in approximately equal increments. Thus in the Pliocene SJB no single determinant of diversity, either physical or biological, overly affected the spatial distribution of the fauna in excess of others altho ugh it is possible that a similar suite of diversity determinants was effective at each divers ity level. Within compiled sample intervals spatial 2 diversity reflects averaged habitat patchiness and thus regional ecosystem carrying capacity (Buzas, 1972) and ecolo gical equivalency, the coexistence of species with effectively identical habitat requirem ents (Shmida and Wilson, 1985), determines faunal structure and diversity. The tem poral change in 2 diversity in the Etchegoin group mollusc fauna is indicative of the loss and expansion of habitat in the SJB through the Pliocene. Spatial and temporal mag nitude of 1 and 2 diversity reflect the environmental controls affecting the endemic fa una.

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164 fluctuations in the San Joaquin Basin (Bowersox, 20 05; Chapter 6), to 4.) 2 diversity, determined by large-scale processes of tectonics an d sedimentation determining basin paleogeography, suggests approximately equal weight of these factors on spatial structure of the fauna. The tentative link between marginal ocean basins an d the open sea makes these basins prone to rapid and substantial environmental variation affecting ecological systems inside the basin that have been documented in the P liocene SJB. Within compiled sample intervals (2 diversity, Fig. 5.18), habitat patchiness is avera ged and regional ecosystem carrying capacity (Buzas, 1972) and ecolo gical equivalency, the coexistence of species with effectively identical habitat requirem ents (Shmida and Wilson, 1985), determines faunal structure and diversity. The temp oral change in 2 diversity in the Etchegoin group mollusc fauna is reflective of the loss and expansion of habitat in the SJB through the Pliocene. Buzas (1972) conjectured that because marine ecosystems quickly reach their carrying capacity in terms of s pecies diversity after an environmental disturbance, new habitats are filled by existing sp ecies thus slowing evolutionary diversification. This is displayed in the Etchegoi n group endemic fauna where diversity did not recover to levels preceding the extinction at the Etchegoin-San Joaquin boundary until new habitats were created with basin flooding during Pecten zone deposition (Fig. 5.16A, 3.1 Ma). A similar pattern is evident in th e diversity and diversification of marine mollusc fauna of the early Middle Miocene Paratethy an marginal sea of east-central Europe reported by Harzhauser et al. (2003). Thus, alpha diversity effectively accounts for spatial distribution and sample-level temporal structure within the Etchegoin group mollusc fauna. The temporal division into 1 diversity (4th-order eustatic cycles) and 2(formations, coincident with 3rd-order eustatic cycles) allows the identification o f environmental controls on community succession and faunal structure; the level of the incrementally larger partition (1–2 increment versus 2–1 increment) indicative of the primary control. This allows determination of local and areal environmental controls on faunal distribution and structure through correlati ve spatial trends in diversity (Poore and Rainer, 1974) that may otherwise not be evident in individual locality collections but are evident by comparison of samples. Marginal ocean b asins (or marginal seas sensu Lotze et al., 2006) are specifically vulnerable to eustat ically-driven environmental variation by their limited connection to the open ocean. In gen eral, these isolated epicontinental seas contain impoverished faunas and display lower diver sity than those of open ocean shelfal environments due to geographic barriers to larval d ispersal and inherent environmental instabilities of marginal marine basins (Kowalewski et al., 2002). For example, peak species richness of the Etchegoin group fauna reach ed at maximum basin flooding during Siphonalia zone deposition (Fig. 5.3) was <70% of the modern San Francisco Bay fauna and possibly as much as 25% less if the effect of t ime averaging on species richness is discounted (see the discussion in Kidwell, 2002). In the Etchegoin group, temporal changes in the str ucture of the endemic mollusc fauna driven by 4th-order eustatic cycles accounts for 37% of 1 diversity and exceeds the contribution of the endemic fauna to total species richness (equation 5). This “excess diversity” of the SJB endemic fauna is indicative o f its stenotopy causing sensitivity to

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165 the environmental changes coincident with regressio n that leave the fauna extinctionprone. That is, adaptation and stenotopy that allo ws an endemic species to successfully exploit its habitat are, in essence, general cases of ‘evolutionary suicide’ (Rankin and Lpez-Sepulcre, 2005) and precursors to extinction. Although the non-endemic Pacific coastal fauna is affected by these same environment al changes, it suffers local extinction of comparatively fewer species while maintaining a core population outside of the SJB. Upon return of favorable environmental conditions i n the SJB, the non-endemic coastal fauna quickly expanded their ranges back into the S JB and habitats vacated by the extinction within the endemic fauna and its own mem bers. Data from the basal Siphonalia zone transgression (Fig.5.13, 5.19) display diversity partitioned approximately equally between 1 and 2 indicative of little faunal variation with scale within and between areas. Transgression allows nor mal-marine adapted taxa to invade and colonize newly appearing habitats in marginal b asins that were previously unavailable. The pioneering taxa will be generalis t species able to tolerate interim environmental conditions followed by a succession o f more specialist forms as the basin evolves towards fully marine conditions (Hetheringt on and Reid, 2003). Species richness of the basal Siphonalia zone non-endemic and endemic faunas increased ~50% beginning ~10 m above the stratigraphic level marking the onse t of transgression (~10 kyr at the average deposition rate of the uppermost Etchegoin Formation) when compared to the underlying Macoma zone and cannot be attributed to range-through spe cies from underlying stratigraphic intervals. The increased species richness comes from the combination of invasion and colonization by Pacific coastal species and diversification of endemic species as new habitats developed during tr ansgression. Temporal 2 diversity of both faunas, however, increased <10% from the Macoma zone to the Siphonalia zone indicative of the new faunal elements being added a t low abundance ranks. Not all new habitats in the Pliocene SJB were equa lly available to both the nonendemic and endemic faunas. The habitat available to each increased as environmental equatability improved as evidenced by the temporal partitioning of 2 diversity between the respective faunas (Fig. 5.16B) as a proxy for h abitat availability. That is, the unique environmental regime of a marginal ocean basin dict ates that some portion of the available habitats will be available to both non-en demic and endemic faunas and some portion will be available only to the stenotopic en demic fauna (Fig. 5.16B). This new habitat comes from the flooding of the low-lying sh ore creating embayments, estuaries, and tidal marshes that will largely be exploited by an endemic stenotopic fauna that diversifies as it occupies the newly-created habita t. In the Pliocene SJB eustatically driven environmental change expanded and contracted the habitat available to the endemic fauna at a rate slightly faster than that o f the shared non-endemic-endemic habitat space (Fig. 5.16B, difference in the slope of the two curves dm = 0.01) although at highest eustatic levels habitat represented by HE comprised 33% of the total habitat represented by HT. For example, a two-meter rise in sea level has a greater impact on the shore where any flooding is a 100% change in water depth and may cover large areas of low-lying land versus offshore areas where a two-me ter water depth increase above water 20 m deep is only a 10% change in depth and habitat s undergo a minor shoreward shift.

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166 Likewise, very shallow-water ocean-marginal and tid al flat environments rapidly become dry land during regression in contrast to relativel y deeper-water nearshore environments that merely retreat basinward. Slow environmental change favors specialist/endemic species whereas moderate to high rates of environme ntal change favors high immigration rates of generalist species over the local competit iveness of specialists (Bowers and Harris, 1994). The greatest force of environmental change for nearshore and shoreline-marginal faunas is sea level change. A r apid sea level rise will favor the establishment of non-endemic generalist species (e. g. Mya ) in shallow water near-shore habitats and tidal flats. A slow sea level rise al lows the endemic fauna to migrate landward and occupy and diversify in the new margin al environments. Under rapid regression the transition of shoreline marginal env ironments to dry land contributes to the extinction of the endemic species of these environm ents that are unable to adapt to the pace of environment change. Rapid early-stage transgression is suggested by tho se intervals ranked 107-97 (ranks 108-116 are monospecific) in Figure 5.16B wh ere there is no endemic-specific habitat available and thus favorable for immigrant generalist taxa from the Pacific, e.g Mya In the basal Siphonalia zone, 12% of all locality collections are comprise d of >50% endemic species, 73 % of locality collections with <50% endemic species (31% of locality collections solely of non-endemic species and 42% with 50-70%by non-endemic species), and the balance of 15% of locality collec tions comprised equally of nonendemic and endemic species. This distribution of non-endemic and endemic species between locality collections is indicative of early -stage eustatic transgression. Nonendemic relicts of the underlying Macoma zone along with newly introduced/reintroduced coastal species dominate 73 % of locality collections prior to diversification of the endemic fauna. Assuming tha t the 12% of locality collections dominated by or comprised solely of endemic species as an estimate of HE/HT then this basal Siphonalia zone 10 m-sample interval falls at about rank 90 o n Figure 5.16B confirming early-stage eustatic transgression and t he onset of diversification within the fauna. Gradual (4th-order) eustatic transgression allows the endemic f auna to diversify and fill additional, new and potentially expanding habitats (e.g., the Pecten zone fauna and specifically Oppenheimopecten coalingensis Stanton and Dodd, 1997; Fig. 5.15B) while the non-endemic fauna expands its range to co lonize the shared habitat. In contrast, during eustatic regression environmental deteriorat ion leads to reduction of available habitat to the point where only shared habitat is a vailable (Fig. 5.16B, rank 97-107). At this environmental extreme, specialist non-endemic species are subject to local extinction and specialist endemic species to total extinction. These processes are illustrated in the Etchegoin group fauna by the sharp increase in the endemic fauna 2 diversity during early Pecten zone deposition (Fig. 5.16A, HE) accompanying the rapid diversification of the fauna (Stanton and Dodd, 1997) followed by an e qually large loss of diversity during regression at the end of the eustatic cycle (Fig. 5 .16A). Because the rate of colonization by non-endemic species exceeds the evolutionary rat e of the endemic fauna, non-endemic generalist species initially dominate shared habita t displacing endemic species into marginal habitat and endemics will be more extinction-prone during small -scale

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167 environmental perturbations than the non-endemic fa una. In summary, increased diversity (H) during transgre ssion occurs as more rare species are added to a fauna; abundant species rema in abundant species. These rare species will largely be those stenotopic specialist s in the endemic faunas of ocean-marginal environments as well as immigrant sp ecialists exploiting an equitable environment inside the basin. These rare species, b y their environmental specialization and dearth of numbers, are more extinction-prone du ring environmental deterioration than the abundant species. Thus environmental chan ge due to transgression and regression will have its biggest impact on the lowranked (rare) species that comprise the tail of the lognormal rank-species richness curve ( e.g. Fig. 5.7A, lower Etchegoin Formation fauna; Fig. 5.7B, Siphonalia zone fauna; Fig. 5.7D, Pecten zone fauna). This is also why a straight line rank-species richness c urve could be interpreted as a fauna under environmental stress that has lost its rare a nd some middle-ranked species (e.g Fig. 5.7A, lower Jacalitos fauna). Displacement of an endemic species by an invading g eneralist has been observed in the modern Wadden Sea, Netherlands, where the in troduction of the Pacific oyster Crassostrea gigas has established new habitat in the shared-habitat zone and displaced the native oyster Ostrea edulis and mussel Mytilus edulis (Reise, 2005). In the modern oceans, the impacts of humans has been substantial and concerns of extinction of marine taxa have been raised (Dulvy et al., 2003; Stockwel l et al., 2003). Human exploitation accounts for 55% of marine species losses in histor ic extinctions while habitat loss from all causes accounts for an additional 37% (Dulvy et al., 2003). In 12 globally distributed, modern estuaries and coastal seas studied by Lotze et al. (2006), human impacts including destruction of seagrass and wetland habitat and deg radation of water quality have depleted >90% of historically important species, in essence transforming these taxa into rare species, and accelerated invasion by non-nativ e species. Furthermore, global sea level is estimated to rise 28-34 cm during the next century (Church and White, 2006) with an additional rise in wave height over the sea-leve l rise of ~40 cm in the North Atlantic (Tsimplis et al., 2005) alone thus flooding tidal m arshes, estuaries, and marginal seas along the Atlantic margin. It has been demonstrate d in this study that eustatic transgression creates both shared habitat and habit at available solely to endemic species and drives invasion and colonization by non-endemic generalist species. Further, some portion of former endemic species habitat is moved into the shared habitat as coastal waters deepen and endemic species are displaced to a fragmented habitat thus impeding adaptation (Stockwell et al., 2003). While there i s a possibility that adaptation and evolution of affected species within the faunas fro m tidal marshes, estuaries, and marginal seas may keep pace with environmental chan ge (Stockwell et al., 2003), this natural succession of species in these environments will accelerate as sea level rises with the consequent likely extinction of the critically depleted faunas. Conclusions1.The Etchegoin group molluscan fauna is dominated by a few abundant generalist bivalves occurring in most habitats, but also consi sts of a large number of

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168 uncommon to rare species. In the Etchegoin group f auna 19% of species account for 67% of all occurrences with the 33% uncommon sp ecies accounting for ~23% of total faunal diversity. 2. There is a direct cross-scale correlation of div ersity with increasing scale from individual locality collections and 10-m sample int ervals (1 and 2 diversity) to 4th-order eustatic and formations (1 and 2 diversity) to the Etchegoin group in toto ( diversity) reflecting the combined heterogeneity a t the lower levels. The contribution of 1 accounts for 62% of 2 and is a reflection of habitat patchiness in the region. At the scale of 4th-order eustatic variations, 1 accounts for ~80% of the total diversity consistent with the eustatic control of Etchegoin group faunal composition Further scaling to 2 diversity, the level of formations and coincident with 3rd-order eustatic cycles, accounts for the ~20% balanc e of the diversity evident in the Etchegoin group faunal com position. 3.Endemic species comprise 30% of the fauna and acc ount for 42% of sample interval diversity indicative of the environmental sensitivi ty of the endemic fauna. Five or fewer endemic species are found in 98% of l ocality collections and 19% of endemic species are found occurring at only a singl e locality. While 23%endemics account for 67% of all occurrences, Pseudocardium densatum alone comprises 22% off all endemic occurrences. 4.At the level of 4th-order eustatic diversity, between-sample 2 diversity accounts for ~80% of the total diversity consistent with the eustatic control of Etchegoin group faunal composition. Complex community struct ure, demonstrated by higher diversity and lower evenness, corresponds to highest eustatic levels thus normal marine conditions and less patchy community distributions. Low diversity and very patchy community distributions correspond to brackish conditions at eustatic lowstand and increasingly brackish conditi ons as the basin shallowed near the end of upper San Joaquin deposition prior to cl osure of the Priest Valley Strait. 5.Spatial scaling of diversity was explored in the basal 10-m sample interval of the Siphonalia zone, middle uppermost Etchegoin. The diversity of the Coalinga Anticline, Jacalitos Anticline, and Kettleman Hills is comparable and relatively low. The Jacalitos Anticline fauna is characterist ic of a tidal-flat habitat where six bivalve species (30% of the fauna) comprise 67% of occurrences. In the outer-bay communities found in the larger and more diverse Co alinga Anticline and Kettleman Hills faunas, 42% of species comprise 67 % of the fauna. Raising scaling to diversity at the levels of locality clusters and a reas suggests a moderate distributional control due to habitat patc hiness. In contrast, ~80% of the Jacalitos Anticline fauna’s diversity is between localities suggesting strong control of faunal distribution due to habitat patch iness on the tidal flat. Diversity and evenness associated with tidal-flat and bay env ironments are consistent with substrate-controlled patchy habitat distribution de monstrated in modern intertidal and nearshore mollusc faunas. 6.Comparison of the Etchegoin group mollusc fauna w ith the contemporaneous

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169 Pliocene fauna from the Santa Maria Basin shows gre ater diversity in the SJB during the warmer early Pliocene and lower diversit y during the middle and late Pliocene when the San Joaquin Basin was generally b rackish environmentally variable. When compared to modern central coastal California estuarine faunas, diversity of early Pliocene faunas from the Jacalit os and Etchegoin formations in toto was higher than modern faunas in toto while diversity of the San Joaquin Formation fauna is comparable to modern faunas from Elkhorn Slough and Mugu Lagoon. However by strict comparison, the greater species richness and diversity of the Etchegoin group fauna stems from time averag ing causing the accumulation of rare species in the fauna. Peak species richnes s of the Etchegoin group fauna reached at maximum basin flooding during Siphonalia zone deposition was <70% of the modern San Francisco Bay fauna and may have been as much as 25% less than that if the effect of time averaging on specie s richness is discounted. 7.Partitioning 2 diversity between non-endemic and endemic species discloses habitat segments as shared non-endemic/endemic spec ies-available habitat and habitat available solely to endemic species. Durin g eustatic transgression endemic habitat expands at a greater rate than the shared h abitat although invading generalist species quickly fill the shared habitat. Endemic taxa rapidly diversify to fill the newly available habitat. However, a portio n of endemic habitat concurrently passes into shared habitat where invad ing generalist species displace endemic species. During eustatic regression endemi c habitat is reduced at a faster rate than shared habitat thus displacing endemic sp ecies and contributing to extinction. 8.During the current period of eustatic sea-level r ise, critically depleted endemic faunas of modern shallow-coastal and ocean-marginal environments will be shifted into a shared-habitat. The implications of this is displacement of the endemic fauna, already at critically low population numbers, by invading nonendemic generalist species with consequent likely e xtinction if adaptation does not keep pace with environmental change. ReferencesAdegoke, O.S., 1969, Stratigraphy and paleontology of the marine Neogene formations of the Coalinga region, California: University of Cali fornia, Publications in Geological Sciences, v. 80, 241 p., 13 pl. Allan, J.D., 1975, The distributional ecology and d iversity of benthic insects in Cement Creek, Colorado: Ecology, v. 56, p. 1040-1053. Arnold, R., 1909, Paleontology of the Coalinga dist rict, Fresno and Kings Counties, California: United States Geological Survey, Bulle tin 396, 173 p., 30 pl. Arnold, R., and Anderson, R., 1910, Geology and oil resources of the Coalinga district, Fresno and Kings Counties, California: United Stat es Geological Survey, Bulletin 398, 354 p.

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170 Bowers, M.A., and Harris, L.C., 1994, A large-scale metapopulation model of interspecific competition and environmental change: Ecological Modeling, v. 72, p. 251-273. Behrensmeyer, A.K., Frsich, F.T., Gastaldo, R.A., Kidwell, S.M., Kosnik, M.A., Kowalewski, M., Plotnick, R.E., Rogers, R.R., and A lroy, J., 2005, Are the most durable shelly taxa also the most common in the mar ine fossil record?: Paleobiology, v. 31, p. 607-623. Bowersox, J.R., 2004, Late Neogene Paleobathymetry, Relative Sea Level, and Basin Margin Subsidence, Northwest San Joaquin Basin, Cal ifornia: American Association of Petroleum Geologists, Search and Dis covery Article 30029, unpaginated [6 p.], Bowersox, J.R., 2005, Reassessment of extinction pa tterns of Pliocene molluscs from California and environmental forcing of extinction in the San Joaquin Basin: Palaeogeography, Palaeoclimatology, Palaeoecology, v. 221, p. 55-82. Brenchley, G.A., 1982, Mechanisms of spatial compet ition in marine soft-bottom communities; Journal of Experimental Marine Biology and Ecology, v. 60, p. 1733. Brett, C.E., 1998, Sequence stratigraphy, paleoecol ogy, and evolution: biotic clues and responses to sea-level fluctuations: Palaios, v. 13 p. 241-262. Buzas, M.A., 1972, Patterns of species diversity an d their explanation: Taxon, v. 21, p. 275-286. Buzas, M.A., and Culver, S.J., 1999, Understanding regional species diversity through the log series distribution of occurrences: Biodiversit y Research, v. 8, p. 187-195. Buzas, M.A., and Gibson, T.G., 1969, Species divers ity: benthonic foraminifera in western North Atlantic: Science, v. 163, p. 72-75. Buzas, M.A., and Hayek, L.C., 2005, On richness and evenness within and between communities: Paleobiology, v. 31, p. 199-220. Cattaneo-Vietti, R., Chiantore, M., Schiaparelli, S ., and Albertelli, G., 2000, Shallowand deep-water mollusc distribution at Terra Nova B ay (Ross Sea, Antarctica): Polar Biology, v. 23, p. 173-182. Church, J. A., and White, N.J., 2006, A 20th centur y acceleration in global sea-level rise: Geophysical Research Letters, v. 33, L01602, doi:10 .1029/2005GL024826. Cotgreave, P., and Harvey, P.H., 1994, Evenness of abundance in bird communities: Journal of Animal Ecology, v. 63, p. 365-374. Denadai, M.R., Amaral, A.C.Z., and Turra, A., 2005, Structure of molluscan assemblages in sheltered intertidal unconsolidated environments : Brazilian Archives of Biology and Technology, v. 48, p. 825-839. Dulvy, N.K., Sadovy, Y., and Reynolds, J.D., 2003, Extinction vulnerability in marine populations: Fish and Fisheries, v. 4, p. 25-64. Fisher, R.A., 1943, Part 3. A theoretical distribut ion for the apparent abundance of different species: Journal of Animal Ecology, v. 12 p. 54-57.

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171 Gering, J.C., Crist, T.O., and Veech, J.A., 2003, A dditive partitioning of species diversity across multiple spatial scales: implications for re gional conservation of biodiversity: Conservation Biology, v. 17, p. 488-4 99. Giosan, L., 2004. Drilling to investigate extreme e nvironmental changes: EOS, Transactions of the American Geophysical Union, v. 85, p. 179. Hammer, ., Harper, D.A.T., and P. D. Ryan, 2001, P AST: paleontological statistics software package for education and data analysis: P alaeontologia Electronica, v. 4, 9p.Hammer, ., Harper, D.A.T., and P. D. Ryan, 2006, P AST PAlaeontological STatistics, ver. 1.40: http://folk.uio.no/ohammer/past/past.pdf accessed February 27, 2006. Harzhauser, M., Mandic, O., and Zuschin, M., 2003, Changes in Paratethyan marine molluscs at the Early/Middle Miocene transition: di versity, palaeogeography and paleoclimate: Acta Geologica Polonica, v. 53, p. 32 3-339. Hayek, L.C., and Buzas, M.A., 1997, Surveying Natur al Populations: New York, New York, Columbia University Press, 563 p. Hetherington, R., and Reid, G.B., 2003, Malacologic al insights into the marine ecology and changing climate of the late Pleistocene-early Holocene Queen Charlotte Islands archipelago, western Canada, and implicatio ns for early people: Canadian Journal of Zoology, v. 81, p. 626-661. Hill, M.O., 1973, Diversity and evenness: a unifyin g notation and its consequences: Ecology, v. 54, p. 427-432. Hoots, H.W., 1930. Geology and Oil Resources Along the Southern Border of San Joaquin Valley, California, United States Geologica l Survey, Bulletin 812-D, p. 243-332. Keen, A.M., 1963, Marine Molluscan Genera of Wester n North America: Stanford, California, Stanford University Press, 126 p. Keen, A.M., 1971, Sea Shells of Tropical West Ameri ca, 2nd Edition: Stanford, California, Stanford University Press, 1064 p. Kidwell, S.M., 2002, Time-averaged molluscan death assemblages: palimpsests of richness, snapshots of diversity: Geology, v. 30, p 803-806. Kidwell, S.M., and Flessa, K.W., 1996, The quality of the fossil record: populations, species, and communities: Annual Review of Earth Pl anetary Sciences, v. 24, p. 435-464. Kidwell, S.M., Frsich, F.T, and Aigner, T., 1986, Conceptual framework for the analysis and classification of fossil concentrations: Palaio s, v. 1, p. 228-238. Kowalewski, M., Grs, K., Nebelsick, J.H., Oschmann W., Piller, W.E., and Hoffmeister, A.P., 2002, Multivariate hierarchical analyses of Miocene mollusk assemblages of Europe: paleogeographic, paleoecolog ical, and biostratigraphic implications: Geological Society of America Bulleti n, v. 114, p. 239-256. Layou, K.M., 2005, Bringing up beta: examining the effects of extinction on diversity with an additive partitioning model [abstract]: Geo logical Society of America, Abstracts with Programs, v. 37, p. 461.

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172 Loomis, K.B., 1988, Paleoenvironmental and paleocli matic interpretation of upper Miocene-Pliocene lithofacies and macrobiota of the Etchegoin group, Jacalitos Canyon, San Joaquin Valley, California, in Graham, S.A., Studies of the Geology of the San Joaquin Basin: Society of Economic Paleo ntologists and Mineralogists, Pacific Section, v. 60, p. 303-318. Loomis, K.B., 1990, Late Neogene depositional hist ory and paleoenvironments of the west-central San Joaquin Basin, California [PhD the sis]: Stanford, California, Stanford University, 594 p. Lourido, A., Gestoso, L., and Troncoso, J.S., 2006, Assemblages of the molluscan fauna in subtidal soft bottoms of the Ra de Aldn (north -western Spain): Journal of the Marine Biological Association of the United Kingdom v. 86, 129-140. Lotze, H.K., Lenihan, H.S., Bourque, B.J., Bradbury R.H., Cooke, R.G., Kay, M.C., Kidwell, S.M., Kirby, M.X., Peterson, C.H., and Jac kson, J.B.C., 2006, Depletion, degradation, and recovery potential of estuaries an d coastal seas: Science, v. 312, p. 1806-1809. MacGinitie, G.E., 1935, Ecological aspects of a Cal ifornia marine estuary: American Midland Naturalist, v. 16, p. 629-765. Madin, J.S., Alroy, J., Aberhan, M., Frsich, F.T., Kiessling, W., Kosnik, M.A., and Wagner, P.J., 2006, Statistical independence of esc alatory ecological trends in Phanerozoic marine invertebrates: Science, v. 312, p. 897-900. Miller, K.G., Kominz, M.A., Browning, J.V., Wright, J.D., Mountain, G.S., Katz, M.E., Sugarman, P.J., Cramer, B.S., Christie-Blick, N., a nd Pekar, S.F., 2005, The Phanerozoic Record of Global Sea-Level Change: Scie nce, v. 310, p. 193-1298. McQuaid, C.D., and Dower, K.M., 1990, Enhancement o f habitat heterogeneity and species richness on rocky shores inundated by sand: Oecologia, v. 84, p. 142-144. Packard, E.I., 1918a, A quantitative analysis of th e molluscan fauna of San Francisco Bay: University of California, Publications in Zool ogy, v. 18, p. 299-336, pl. 1213. Packard, E.I., 1918b, Molluscan fauna of San Franci sco Bay: University of California, Publications in Zoology, v. 14, p. 199-452, pl. 1460. Patzkowsky, M.E., 2005, Additive diversity partitio ning of a marine biotic invasion: upper Ordovician of the Cincinnati Arch [abstract]: Geological Society of America, Abstracts with Programs, v. 37, p. 461. Pielou, E.C., 1966, The measurement of diversity in different types of biological collections: Journal of Theoretical Biology, v. 13, p. 131-144. Poore, G.C.B., and Rainer, S., 1974, Distribution a nd abundance of soft-bottom molluscs in Port Phillip Bay, Victoria, Australia: Australia n Journal of Marine and Freshwater Research, v. 25, p. 371-411. Rankin, D.J., and Lpez-Sepulcre, A., 2005, Can ada ptation lead to extinction?: Oikos, v. 113, p. 616-619. Reise, K., 2005, Coast of change: habitat loss and transformations in the Wadden Sea: Helgoland Marine Research, v. 59, p. 9-21.

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173 Rousseau, R., and van Hecke, P., 1999, Measuring bi odiversity: Acta Biotheoretica, v. 47, p. 1-5. Shannon, C.E., 1948, A mathematical theory of commu nication: Bell System Technical Journal, v. 27, p. 379-423, 623-656. Shmida, A., and Wilson, M. V., 1985, Biological det erminants of species diversity: Journal of Biogeography, v. 12, p. 1-20. Stanton, R.J., Jr., and Dodd, J.R., 1970. Paleoecol ogic techniques – comparison of faunal and geochemical analysis of Pliocene paleoenvironme nts, Kettleman Hills, California. Journal of Paleontology, 44: 1092-1121. Stanton, R.J., Jr., and Dodd, J.R., 1972. Pliocene cyclic sedimentation in the Kettleman Hills, California, in Rennie, E.E., ed., Guidebook to Geology and Oil Fields, West Side Central San Joaquin Valley: American Associati on of Petroleum Geologists, Pacific Section, pp. 50-58. Stanton, R.J., Jr., and Dodd, J.R., 1997. Lack of s tasis in late Cenozoic marine faunas and communities, central California. Lethaia, 30: 239-2 56. Stockwell, C.A., Hendry, A.P., and Kinnison, M.T., 2003, Contemporary evolution meets conservation biology: Trends in Ecology and Evoluti on, v. 18, p. 94-101. Teske, P.R., and Woolridge, T.H., 2003, What limits the distribution of subtidal macrobenthos in permanently open and temporarily op en/closed South African estuaries? Salinity vs. sediment particle size: Est uarine, Coastal and Shelf Science, v. 57, p. 225-238. Therriault, T.W., 2002, Temporal patterns of divers ity, abundance and evenness for invertebrate communities from coastal freshwater an d brackish water rock ponds: Aquatic Ecology, v. 36, p. 529-540. Tsimplis, M.N., Woolf, D.K., Osborn, T.J., Wakelin, S., Wolf, J., Flather, R., Shaw, A.G.P., Woodworth, P., Challenor, P., Blackman, D., Pert, F., Yan, Z., and Jevrejeva, S., 2006, Towards a vulnerability assess ment of the UK and northern European coats: the role of regional climate variab ility: Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, v. 363, p. 1329-1358. Tunberg, B., 1981, Two bivalve communities in a sha llow and sandy bottom in Raunefjorden, western Norway: Sarsia, v. 66, p. 257 -266. Volkov, I., Banavar, J.R., Hubbell, S.P. and Marita n, A., 2003. Neutral theory and relative species abundance in ecology. Nature, 424: 1035-1037. Wagner, H.H., Wildi, O., Ewald, K.C., 2000, Additiv e partitioning of plant species diversity in an agricultural mosaic landscape: Land scape Ecology, v. 15, p. 219227. Warme, J.E., 1971, Paleoecological aspects of a mod ern coastal lagoon: University of California, Publications in Geological Sciences, v. 87, 131 p. Wignall, P.B., 1993, Distinguishing between oxygen and substrate control in fossil benthic assemblages: Journal of the Geological Soci ety, v. 150, p. 193-196.

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174 Williamson, M., and Gaston, K.J., 2005, The lognorm al distribution is not an appropriate null hypothesis for species-abundance distribution: Journal of Animal Ecology, v. 74, p. 409-422. Wilsey, B.J., and Polley, H.W., 2004, Realistically low species evenness does not alter grassland species-richness-productivity relationshi ps: Ecology, v. 85, p. 26932700. Wilson, J.B., Steel, J.B., King, W. McG., and Gitay H., 1999, The effect of spatial scale on evenness: Journal of Vegetation Science, v. 10, p. 463-468. Woodring, W.P. and Bramlette, M.N., 1950. Geology a nd Paleontology of the Santa Maria District, California. United States Geologica l Survey Professional Paper 222, 185 pp. Woodring, W.P., Stewart, R., and Richards, R.W., 19 40, Geology of the Kettleman Hills oil field, California: USGS Professional Paper 195, 170 p. 56 pl. Wornardt, W.W., Shaffer, B. and Vail, P.R., 2001. R evision of the Late Miocene, Pliocene, and Pleistocene sequence cycles [abstract ]. American Association of Petroleum Geologists Bulletin, 85: 1710.

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175 Chapter 6 Reassessment of Extinction Patterns of Pliocene Mol luscs from California and Environmental Forcing of Extinction in the San Joaq uin Basin AbstractThirty latest Miocene through Late Pleistocene moll uscan faunas from coastal California and the San Joaquin Basin (SJB), central California were reviewed to better understand the pattern of Pliocene mollusc extinction in Calif ornia and particularly in the Etchegoin group (informal SJB nomenclature). Species lists w ere compiled for each fauna, taxonomy reviewed to eliminate synonyms and uncerta in identifications, and the extinct versus living status of each species determined. I found only 34% of molluscan species, 40% of bivalves and 21% of gastropods, in the Etche goin group are extant as compared to 61% of molluscs, 64% of bivalve and 56% of gastr opod species, in Pacific coastal faunas. The Etchegoin group was deposited in a mar ginal basin connected to the Pacific Ocean through a long and narrow silled strait subje ct to its connection being cut by eustatic regression and regional tectonism. Seven major regional extinctions affected the Etchegoin group molluscan faunas where >40% species became extinct: two in the Early Pliocene upper Etchegoin Formation at 4.4 and 4.0 M a and five in the Early-Late Pliocene San Joaquin Formation at ~4.0, 2.9, 2.6, an d 2.4 Ma and that coincident with the final ocean connection closure at 2.3 Ma. Peak div ersity corresponded with periods of highest sea-level at ~4.5, 4.2, 3.1, 2.7, 2.5 and 2. 4 Ma when immigrant faunas became established during periods of warm climate and norm al-marine conditions. Upon sealevel fall the basin became cooler, brackish, and f aunas adapted to warmer and normal marine conditions became extinct with slow recovery of diversity afterwards. Lowdiversity faunas characterize periods of low and ri sing sea level when circulation through the connecting strait was insufficient to maintain normal marine conditions thus hindering establishment of most immigrants from coa stal faunas. Restricted circulation with the Pacific substantially reduced the nutrient supply to the basin leading to a longterm productivity collapse that exacerbated the eff ects of a deteriorating environment thus leading to the major extinction event observed at the Etchegoin-San Joaquin formations contact at 4.0 Ma. Increasing restricti on from the Pacific Ocean during the Pliocene limited immigration of coastal species int o the San Joaquin Basin to those opportunistic species best able to adapt to the env ironment inside the basin while species unable to adapt to conditions inside the SJB were f iltered-out in the strait. Stenotopy of endemic species precluded range expansion through t he connecting strait into the Pacific Ocean. Thus, abrupt regression-driven hydrologic c hange, productivity collapse from coincident geochemical and sedimentary change, and climatic change led to the major extinction events in the Pliocene SJB. Speciation events following extinctions suggest

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176 diversification of surviving faunas into habitats c reated by changed environmental conditions. Despite the number and wide geographic distribution of faunas reviewed in this paper, only 50-90% of extant mollusc species f ound in Pliocene Etchegoin group faunas are also found in coastal California Pliocen e faunas demonstrating the incompleteness of the California fossil record.Publication Citation: Bowersox, J.R., 2005, Reassessment of extinction p atterns of Pliocene molluscs from California and environmental forcing of extinction in the San Joaquin Basin: Palaeogeography, Palaeoclimatology, Palaeoecology, v. 221, p. 55-82. www.sciencedirect.com/science/journal/00310182: doi :10.1016/j.physletb.2003.10.071 Introduction and Previous Work The extinction pattern of North American Pliocene m olluscs is well documented in the literature. Stanley and Campbell (1981) rep orted that only ~20% of bivalve and gastropod species from Western Atlantic provinces a re extant. Later, Stanley (1986) reported that only 22% of Early Pliocene molluscan species and 41% of latest Pliocene species found in Atlantic Coastal Plain margin depo sits from Virginia to Florida are extant. Furthermore, Allmon et al. (1993) document ed 70% extinction among the molluscan faunas from the Late Pliocene Pinecrest B eds in west-central Florida. The pattern, then, is for 60-85% extinction of Pliocene molluscan species on the Atlantic and Gulf of Mexico coasts. Stanley and Campbell (1981) and Stanley (1986) attributed these extinctions to cooling of Atlantic waters during pe riods of Late Pliocene glaciation while arguing sea-level fall as proxy for habitat loss ha d little effect on Western Atlantic molluscan faunas. Clarke (1993) concluded that ext inction of West Atlantic molluscs due to ocean cooling (Stanley and Campbell, 1981; S tanley, 1984; Stanley, 1986) was a reasonable inference in that all surviving Early Pl iocene bivalves in Florida range into temperate waters (Stanley, 1984). Allmon et al. (1 996) and Allmon (2001) suggested that Pliocene molluscan extinctions in the eastern Gulf of Mexico and Western Atlantic resulted, at least in part, from a dramatic decreas e in biological productivity in these waters during the Late Pliocene as a consequence of the initiation of North Atlantic Deep Water formation in the North Atlantic and a decline in upwelling in the eastern Gulf of Mexico. Herbert (2003) suggested that an uncertain nutrient supply due to a decrease in the predictability of upwelling after 2.5 Ma, hence a decrease in productivity similar to that as postulated by Allmon et al. (1996) and Allm on (2001, contributed to Late Pliocene mollusc extinctions on the west Florida sh elf. In contrast to the Atlantic Pliocene molluscan exti nction patterns, Stanley (1986) reported that the Lyellian percentage – the percent age of species in the assemblage that are extant – for all California Pliocene molluscs i s ~71% and 63% for the combined faunas from the Late Pliocene Careaga Formation of the Santa Maria Basin and Early Pliocene Etchegoin Formation of the San Joaquin Bas in (SJB)(Stanley, 1986). Apparently lowering of sea-level in California, a l oss of shelf habitat, produced no excessive regional extinction of Pliocene molluscs (Stanley and Campbell, 1981) and a similar pattern has been documented for the Califor nia Pleistocene by Valentine and Jablonski (1991). Likewise, ocean cooling merely s hifted the Northeast Pacific thermally-controlled molluscan provinces southward and did not led to excessive

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177 extinction of Pliocene Pacific molluscan faunas (St anley, 1986). However Arnold (1909, p. 45) and Arnold and Anderson (1910, p. 139) repor ted 35% extant species and Nomland (1917a) found that ~39% of species from the Etchegoin Formation, and only ~23% of species found in the correlative San Pablo F ormation of Northern California, are extant. These values are comparable to those of We stern Atlantic populations reported by Stanley and Campbell (1981), Stanley (1986), and Allmon et al. (1993). Subsequent workers reported similar proportions of extant spec ies in faunas from the Pliocene Etchegoin group (informal SJB nomenclature, discuss ed below). Loomis (1990a, 1990b), using an updated taxonomy and eliminating s ynonyms, noted that only 33% of species occurring in the Early-Late Pliocene Etcheg oin group in toto and 44% of mollusc species from the basal upper San Joaquin Formation Pecten zone of Woodring et al. (1940) in the Kettleman Hills (Stanton and Dodd, 19 97, fig. 3) are extant. Bowersox (2003) noted that extinction of San Joaquin Basin m olluscs approximates that of the West Atlantic faunas. In light of these apparent contradictions to Stanle y et al. (1980), Stanley and Campbell (1981), and Stanley (1986), this paper rea ssesses the extinction of Pliocene molluscs from the Pacific coast of California and t he SJB. Extinction, diversity, and endemism of the SJB faunas are reinterpreted in the context of marine paleoenvironmental variability in paleogeographical ly restricted marginal oceanic basin. Methodology Locations of molluscan faunas from latest Miocene t hrough Late Pleistocene formations of California reviewed in this paper are shown in Figure 6.1 and their updated median numeric age and correlation in Figure 6.2. Initially, I reviewed the extinction of the seven Late Miocene through Pliocene mollusc fau nas cited in Stanley et al. (1980, fig. 1; Table 6.1). Each of these faunas are chara cteristic of shallow-water, nearshore marine environments. From Stanley et al. (1980, fi g. 1) I scaled the percent extant species and corresponding age for each of the seve n faunas and summarized these data for the relative proportions of gastropods and biva lves in Table 6.1. In order to prepare the faunal data set for analysis, the composition o f each of the seven faunas cited in Stanley et al. (1980, fig. 1) was reviewed and upda ted to the current accepted to remove synonymous species and uncertain identifications (s p., aff., ident., and “?”). No new species were erected, the accepted ranges of specie s were not revised, and the manner of these revisions was uniformly applied to all faunas in this study. Details of the faunal compositions are in Table 6.1. The status of speci es, extinct versus living, were gleaned from Grant and Gale (1931), Merriam (1941), Reinhar t (1943), Keen and Bentson (1944), MacNeil (1965), Addicott (1965a), Morris (1 966), Adegoke (1969), McLean (1969, 1978), Keen (1971), Hertlein and Grant (1972 ), Kern (1973), Kennedy (1974), Marincovich (1977), Bernard (1983), Moore (1983, 19 84, 1987, 1988, 1992, 1999, 2003), Turgeon et al. (1988), McLean and Gosliner ( 1996), Coan and Scott (1997), and Scott and Blake (1998). Following this initial review, I expanded my analys is to a larger study of 30 latest Miocene through Late Pleistocene molluscan faunas ( Table 6.2-6.3, and Fig. 6.1-6.2), including the seven faunas investigated by Stanley et al. (1980), to better understand the pattern of Pliocene mollusc extinction in Californi a, particularly in the SJB. The

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178 Figure 6.1. Location of latest Miocene through Late Pleistocen e faunas reviewed in this study. Correlations are shown in Figure 2: 1 -3. S anta Margarita Formation; 4. Castaic Formation; 5a-c. Purisima Formation; 6. Pancho Rico Formation; 7. lower Rio Dell Formation; 8. Merced Formation; 9a. upper Sisquoc F ormation; 9b. Foxen Mudstone; 9c. Cebada Sand; 9d. Graciosa Sand; 10. Towsley Formati on; 11. upper Capistrano Formation; 12. lower Saugus Formation; 13. upper Fernando Form ation; 14. San Diego Formation; 15af. Etchegoin Group; 16a. middle “San Pedro” Format ion,; 16b. upper “San Pedro” Formation; 17. Pt. Ao Nuevo Late Pleistocene marin e terrace deposits; 18. Cayucos Late Pleistocene marine terrace deposits; 19. Bay Point Formation. Sources for the faunas are given in Appendix 1.

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179 Figure 6.2. Correlation of the Late Neogene formations in Cen tral and Southern California in this study. Correlations are compiled and modif ied from these sources: a. Humboldt Basin from Martin (1916), Faustman (1964), Harris ( 1987); b. San Francisco Bay region from Glen (1959), Bedrossian (1974); c. La Honda Basin and associated tectonic blocks from Powell (1998, figs. 2-4, and sources cited the rein); d. Salinas Basin and adjacent central coastal basin from Hall (1962), Durham and Addicott (1965), Durham (1974), Dorhenwend (1979), Whittlesey (1998); e. SJB from Adegoke (1969), Sarna-Wojcicki, et al (1979), Perkins (1987), Loomis (1990b), Bowersox (1990, 2003, and unpublished data); f. Santa Maria Basin from Woodring and Bramlette (195 0), Barron and Baldauf (1986), Namson and Davis (1993), Barron (1992, fig. 9), Beh l and Ingle (1995); g. Ventura basin from Stanton (1966), Kern (1973); h. San Diego embayment from Elliott (1973), Mandel (1973), Wagner et al. (2001). Numbering of stratig raphic units corresponds to Figure 6.1. Not shown are the Late Pleistocene central coastal California terrace deposits (numbers 1718).

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180

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181 Table 6.2. Age and percent of fauna surviving to the Holocene for faunas reviewed in this paper. Locations and references for each faun a are given in Figure 1. Details of the composition of each fauna are given in Appendix 1. Numerical age assignments are from Figure 2. For this paper I have defined the latest Miocene (LM) as formation category as correlative with the Santa Margarita Formation and early Pliocene (EP), middle Pliocene (MP), late Pliocene (LP) formation categories as co rrelative with the Jacalitos, Etchegoin, and San Joaquin formations, respectively. The Plei stocene (PL) age category assignment includes all Pleistocene formations.

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182

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183 Table 6.3. Sources of Late Neogene central and southern Calif ornia mollusc faunas. Locations are shown in Figure 6.1 and correlation i n Figure 6.2. The numerical age assigned to each fauna is the midpoint of the forma tion age from Figure 6.2. 1. Santa Margarita Formation (Hall, 1962; Durham, 197 4); 2. Santa Margarita Formation (Arnold, 1909; Arnold an d Anderson, 1910; Nomland, 1917b; Preston, 1931; Hall, 1960, Table 4; Addicot t and Vedder, 1963; Addicott, 1965b; Adegoke, 1969; Cote, 1991); 3. Santa Margarita Formation (Arnold, 1909; Arnold an d Anderson, 1910; Nomland, 1917b; Hall, 1960, Table 4; Adegoke, 1969; Cote, 19 91); 4. Castaic Formation (Stanton, 1966); 5a-c. Purisima Formation (Powell, 1998, and sources cited therein); 6. Pancho Rico Formation (Durham and Addicott, 1965); 7. lower Rio Dell Formation (Stewart and Stewart, 1949 ; Faustman, 1964; Harris, 1987); 8. Merced Formation (Glen, 1959; Bedrossian, 1974); 9a-d. Santa Maria Basin (Woodring and Bramlette, 1950); 10. Towsley Formation (Kern, 1973); 11. upper Capistrano Formation (Kern and Wicander, 197 4); 12. lower Saugus Formation (Groves, 1991); 13. upper Fernando Formation (Yerkes, 1972); 14. San Diego Formation (Rowland, 1972; Ashby and Minc h, 1984); 15a. Jacalitos Formation (Arnold, 1909; Arnold and Ande rson, 1910; Nomland, 1917a; Adegoke, 1969; Loomis, 1990b); 15b. Jacalitos Formation (Nomland, 1916; Nomland, 1917a) ; 15c. Etchegoin Formation (Arnold, 1909; Arnold and Ande rson, 1910; Nomland, 1917a; Woodring, et al, 1940; Adegoke, 1969; Loomis 1990b); 15d. Etchegoin Formation, Glycymeris zone (Arnold, 1909); 15e. San Joaquin Formation (Arnold, 1909; Arnold and And erson, 1910; Woodring, et al, 1940; Adegoke, 1969; Loomis, 1990b); 15f. San Joaquin Formation, Pecten zone, west-central SJB (Woodring et al., 1940; Stanton and Dodd, 1997, fig. 3); 16a-b. “San Pedro” Formation (Powell and Stevens, 2000, a nd sources cited therein); 17. Pt. Ao Nuevo Late Pleistocene marine terrace depos its, central coastal region (Addicott, 1966); 18. Cayucos Late Pleistocene marine terrace deposits, c entral coastal region (Valentine, 1958); 19. Bay Point Formation, San Diego (Kern, et al, 1971)

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184 method of Stanley et al. (1980), which included onl y faunas with at least 12 species of bivalves and gastropods, each was followed. Faunas were correlated and assigned a median numeric age from Figure 6.2 and, to prepare the data set for analysis, each compiled fauna was reviewed and updated to the curr ent accepted taxonomy to remove synonymous species and uncertain identifications as outlined above. These additional faunas were selected as characteristic of shallow-w ater, nearshore marine environments and range north-to-south from the cool-water fauna from the lower Rio Dell Formation of the Humboldt Basin in northern California to the te mperate fauna from the San Diego Formation in southern California (Fig. 6.1). The s hallow-water fauna of the lower Rio Dell Formation (Roth, 1979) is found associated wit h deep-sea fan deposits (Ingle, 1976; McCrory, 1995) suggesting taphonomic displacement t o deep water by turbidity currents as reported in the upper Capistrano Formation by Ke rn and Wicander (1974) and in the Late Miocene Santa Margarita Formation of Dibblee ( 1973) by Kiser et al. (1988). Bivalve and gastropod faunas were also reviewed sep arately to determine the extinction patterns for each class and then compared. Unlike Stanley et al. (1980), I compiled multiple published faunas from a formation, where a vailable, to get the largest possible fauna in each case and mitigate the possibility of bias from the “lumping” or “splitting” of taxa by individual authors, particularly in earl y descriptive paleontology studies. The Jacalitos Formation of Arnold and Anderson (1910) a nd Nomland (1916, 1917a) includes much of what is now correlated and mapped as lower Etchegoin Formation (Adegoke, 1969; Loomis, 1990b; Hall and Loomis, 1992), and th e Etchegoin Formation of Arnold and Anderson (1910) and Nomland (1917a) includes th e later defined San Joaquin Formation. Faunas from these authors were correlat ed as shown in Figure 6.2 and Table 6.3. For additional comparisons, Pliocene faunas were di vided into two geographic groups: 15 faunas from the Pacific coast and coasta l basins and six from the SJB (Table 6.2-6.3). Within these geographic groups faunas we re then categorized as latest Miocene and early, middle, and late Pliocene (Table 6.2) an d averaged for further comparison (Table 6.4). Pleistocene faunas were averaged as o ne for constructing Table 6.4. Average values presented in Tables 6.1-6.2 and Tabl e 6.4 are not weighted for the relative difference in bivalve and gastropod fauna sizes because the difference between an unweighted average and weighted average values i s within the rounding to whole percentages.Etchegoin Group Stratigraphy and Faunal Data Set Three formations comprise the Pliocene Etchegoin gr oup (informal SJB nomenclature): the Jacalitos Formation, Etchegoin F ormation, and San Joaquin Formation. The Etchegoin group overlies latest Mio cene and earlier strata and is overlain by the latest Pliocene-Pleistocene Tulare Formation (Fig. 6.2). The northwestern SJB remained near sea level throughout the late Neogene despite lying on a tectonically active basin margin thus deposition of the Etchegoin group kept pace with basin subsidence (Bowersox, 2004a). The thick succ ession of non-marine to shallowmarine facies of the Etchegoin group has been measu red and described from outcrops along the northwestern San Joaquin Basin margin in several studies (Arnold and Anderson, 1910; Woodring et al., 1940; Adegoke, 196 9; Stanton and Dodd, 1976;

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185 Loomis, 1990b; Hall and Loomis, 1992): the Jacalito s Formation (635 m thick, this study as adapted from Hall and Loomis, 1992; Fig. 6.2, ~5 .3-4.8 Ma), Etchegoin Formation (1060 m thick, this study as adapted from Hall and Loomis, 1992; Fig. 6.2, ~4.8-4.0 Ma) which includes the uppermost Etchegoin Formation ex posed in the Kettleman Hills (~200 m thick, Woodring et al., 1940), lower San Joa quin Formation (400 m thick, this study as adapted from Woodring et al., 1940; Fig. 6 .2, 4.0-3.1 Ma) and upper San Joaquin Formation (335 m thick, this study as adapt ed from Woodring et al., 1940; Fig. 6.2, 3.1-2.3 Ma). This study is based on presenceabsence faunal data from the Etchegoin group collected from a total of 563 local ities by previous workers where I could verify the stratigraphic position and my coll ections from 102 localities on the western and southern margins of the SJB made during 1999-2004. Arnold (1909) and Arnold and Anderson (1910) collected from 92 locali ties throughout the Etchegoin group in the Coalinga, Kettleman Hills, and Kreyenhagen H ills areas. Extensive collections by Woodring et al. (1940) from 297 localities in the u ppermost Etchegoin and San Joaquin formations in the Kettleman Hills comprise more ~50% of the data I compiled for the Etchegoin group. Adegoke (1969) and Loomis (1990b) collected from a total of 174 localities primarily in the Jacalitos and Etchegoin formations in the Coalinga and Kreyenhagen Hills areas. Together these faunas for m a stratigraphically constrained database that includes the entire Etchegoin group f auna, and this database serves as the basis for my interpretations.Results Results of this paper are presented in Tables 6.1 a nd 6.2 and Figures 6.3-6.8. Stanley et al. (1980) found 33% of all latest Mioce ne molluscs are extant whereas I found this to be 35%, a small difference overall, but I f ound proportionally fewer extant gastropods and more extant bivalves (Table 6.1). I n the Pliocene faunas, Stanley et al. (1980) found an average of 65% of all molluscs, 69% of bivalves and 61% of gastropods, extant in the four faunas from coastal basins and a n average of 54% of molluscs, 60% of bivalves and 44% of gastropods, extant in the two E tchegoin group faunas (Fig. 6.3, Table 6.1). Using identical faunas, I found an ave rage of 62% of all species in the four coastal basin Pliocene faunas extant and only 36% o f the Etchegoin group fauna extant (Fig. 6.3, Table 6.1). Pliocene faunas from coasta l basins had 2% fewer extant bivalves and 6% fewer extant gastropods as compared to the v alues obtained by Stanley et al. (1980). In the larger study (Fig. 6.4-6.5, Table 6.2), the four latest Miocene faunas average 44% extant bivalves, 22% extant gastropods, and 36% overall extant mollusc species. An average of 61% of mollusc species, 64% of bivalves and 56% of gastropods, found in 15 Pacific coastal Pliocene faunas are ext ant which is ~4% less than that found by Stanley et al. (1980). I found that the Etchego in group fauna has an average of 34% extant species including 40% extant bivalves and 21 % extant gastropods (Table 6.2). Table 6.4 and Fig. 6.6 compare the average percent of extant species in faunas from Pacific coastal basins with correlative early, midd le, and late Pliocene SJB faunas as defined above. Faunas from Pacific coastal basins show the Lyellian distribution of an increasing proportion of extant species in the faun as from 36% in the latest Miocene to 65% in the Late Pliocene and 94% in the Pleistocene in a pattern similar to that described

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186 Figure 6.3. Comparison of Stanley, et al (1980) with this pape r of the percent of latest Miocene and Pliocene faunas surviving to the Holoce ne. Numbering corresponds to Figures 6.1-6.2 and Table 6.1. Survivorship was fo und to be slightly to substantially different in this paper than that determined by Sta nley et al. (1980, fig. 11).

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187 Figure 6.4. Percent of each latest Miocene through Late Pleist ocene fauna surviving to the Holocene. Numbering of stratigraphic units cor responds to Figures 6.1-6.2 and Table 6.2.

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188 Figure 6.5A. Proportion of extant bivalve species in latest Mio cene through Late Pleistocene faunas from Pacific coastal California and the SJB of central California. Coastal faunas generally follow the Lyellian patter n of an increasing proportion of extant species as the faunas become progressively younger. Faunas from the SJB show a relatively even and lower proportion of extant spec ies in faunas of all ages.

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189 Figure 6.5B. Proportion of extant gastropod species in the same faunas. While the patterns are more scattered, the coastal faunas sho w a Lyellian pattern of extant species while the SJB faunas again show a pattern of low an d relatively even proportion of extant species.

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190 Figure 6.6. Comparison of the proportion of extant species in latest Miocene through Pleistocene faunas from Pacific coastal basins and the SJB. For this figure faunas were grouped as correlative to the Santa Margarita Forma tion (latest Miocene), Jacalitos Formation (early Pliocene), Etchegoin Formation (mi ddle Pliocene), and San Joaquin Formation (late Pliocene). Groupings are given by fauna in Table 6.2. Faunas from coastal basins show a Lyellian extinction pattern o f a progressively larger proportion extant species as faunas approach the recent while faunas from the SJB show sea-level driven extinction.

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191 by Stanley et al. (1980). Whereas SJB faunas show approximately the same proportion of extant species in the latest Miocene, 34% extant SJB species versus 36% in coastal faunas, Pliocene faunas show only a modest increase in extant species from 29% in the early Pliocene to 40% in the late Pliocene (Fig. 6. 4). Discussion While I could not exactly replicate the results of Stanley et al. (1980), our results are generally in agreement for the Pliocene Pacific coastal basins of California (Table 6.1-6.2, Fig. 6.3-6.5). However, there are differe nces between this study (Table 6.1; Fig. 6.3) and those of Stanley et al. (1980) for all fau nas. Comparing Stanley et al. (1980) and this study (Table 6.1), differences in results fall into four areas: 1.) ambiguous sources of faunas from the Santa Margarita and San Diego forma tions; 2.) possible differences in the preparation of the basic faunal data sets by re duction of the species lists for synonymy of the Cebada, Lower Merced, and Pancho Ri co faunas, and the bivalve portion of the San Diego fauna; 3.) a correlation r evision post-publication of Stanley et al. (1980) for the Jacalitos Formation of Nomland ( 1916, 1917a); and 4.) a mistake by Stanley et al. (1980) in the analysis of the Etcheg oin Glycymeris zone fauna of Arnold (1909). Additional information provided by Steven M. Stanley (personal communication, 2003) showed the source of the Santa Margarita Formation fauna to be Table 4 of Hall (1960). Stanley et al. (1980) cite d Hertlein and Grant (1972) as the source of their San Diego Formation fauna including both bivalves and gastropods. However, Hertlein and Grant (1972) include only the bivalves from the San Diego Formation with no references to gastropods. Lackin g the source of the gastropod fauna from the San Diego Formation in Stanley et al. (19 80), there is not a direct comparison of my results (Table 6.2) to Stanley et al. (1980) and my Table 6.1. Because sources of the Cebada, Lower Merced, and Pancho Rico faunas, a nd the bivalve portion of the San Diego fauna are clear, the differences in results f or these faunas (Table 6.1) and Stanley et al. (1980) cannot be satisfactorily explained. In the case of the Jacalitos Formation, Stanley et al. (1980) cited Nomland (1916, 1917a) w ho, in turn, used the definition of the Jacalitos Formation of Arnold and Anderson (1910) t hus this fauna may include elements that might otherwise be assigned to the Etchegoin F ormation. For the Etchegoin Glycymeris zone fauna of Arnold (1909), despite using the sam e data set, our results are substantially different. The results of this study are nearly identical to those of Arnold (1909) and Loomis (1990a, 1990b) suggesting a mista ke in Stanley et al. (1980). Synonyms alone do not explain the differences betwe en this study and Stanley et al. (1980) and including synonymous species would not s ubstantially change the results. The difference in the proportion of extinct species in the Etchegoin Formation, reduced for synonymy, is very small. Arnold (1909) recogni zed that 35% of molluscs found in the Etchegoin Formation are extant while Loomis (19 90a), using current taxonomy, found this to be 33%. In Arnold’s (1909) Glycymeris zone fauna, synonyms would add an additional three species, including one extinct species, to the 46 species in the fauna. In Nomland’s (1916) Jacalitos Formation fauna, syno nyms would add one extinct species to the 77 species in the fauna. Neither th e Glycymeris zone fauna of Arnold (1909) nor the Jacalitos Formation fauna of Nomland (1916) includes species with uncertain identifications. These differences affec t how the processes driving Pliocene

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192 molluscan extinction in the SJB have been understoo d. Figure 6.7 compares the proportion of extant specie s in Pliocene SJB faunas with those from the two most paleogeographically-related sections on the Pacific Coast of California: the Purisima Formation, which was depos ited on the Pacific shelf beyond the terminus of the Priest Valley Strait (Fig. 6.8), an d the Santa Maria Basin section, which was deposited at the location of the latest Miocene southern connection of the SJB to the Pacific Ocean (Harris, 1987, fig. 28, and sources t herein; Fig. 6.8). Both the Purisima Formation and Santa Maria Basin faunas reflect the Lyellian pattern (Fig. 6.7) suggesting that this pattern underscores the fundamental extin ction pattern among mollusc faunas from the California Pacific Coast. Although Stanto n and Dodd (1997, p. 253) contended that the continuity of faunal change they documente d in the Pliocene SJB paralleled at a broader scale the Lyellian gradient documented for Pacific coastal faunas (Stanley et al., 1980; this study), this study does not support thei r contention. The extinction of molluscs in the Pliocene SJB averaged nearly twice that of coastal California throughout the Pliocene and its magnitude changes little from Early to Late Pliocene. The difference in extinction patterns of the Pliocene mollusc faun as from coastal California and the SJB is due to the unique paleogeographic configuration of the Pliocene SJB and how this controlled the marine environment within the basin. Because the Pliocene SJB was a marginal basin with a tenuous connection to the Pacific ocean, extinction events within the basin a re not unexpected. Extinction in the Pliocene SJB, as seen in abrupt diversity reduction observed in the fossil record, may include any or all of three contributing processes: 1.) migration, 2.) local extinction, and 3.) total extinction of endemic species. Migration may occur when a species originating inside the basin extends its range to a more favora ble environment on the adjacent coast and leaves no population behind. Local extinction occurs where an immigrant coastal species has its biogeographic range truncated by th e extinction of the portion of its population inside the basin while its core populati on remains on the coast. Many waves of immigration may be associated with local extinct ions. In the SJB total extinction of an endemic species is still a local event because its fossil record is restricted to the basin. Thus, as used herein for the purpose of this paper, extinction may include any of the processes discussed above.Pliocene SJB Paleogeography and Marine Paleoenviron ment Variability The Pliocene SJB was a shallow marginal basin 175 k m long, 100 km wide (Fig. 6.8) ringed by estuaries, tidal marshes, and tidal deltas (Loomis, 1988, 1990b; Reid, 1995). Until the end of the Miocene, there were tw o connections between the SJB to the Pacific Ocean: through Priest Valley on the northwe stern margin, and a seaway on the southwestern margin connecting to the ocean through the Santa Maria Basin (Bandy and Arnal, 1969, fig. 22; Harris, 1987, fig. 28, and so urces therein). The current phase of Temblor Range and southern Coast Ranges uplift (beg inning by ~5.4 Ma; Miller, 1999) closed the southern seaway (Harris, 1987) leaving t he ~30 km long and ~13 km wide Priest Valley Strait as the sole connection to the Pacific Ocean (Loomis, 1990b; Powell, 1998; Fig. 6.8). Shallow-water macrofauna collecte d from the Etchegoin group in the Priest Valley Strait (Arnold, 1909; Arnold and Ande rson, 1910; Nomland, 1917a; Rose and Colburn, 1963; Merrill, 1986; this study) sugge st a depth at maximum transgression

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193 Figure 6.7. Comparison of the proportion of extant species fro m Pacific coast faunas and the SJB. The Purisima Formation was deposited in the region where the Priest Valley Strait connected with the Pacific Ocean (Loo mis, 1990b). The SJB connected to the Pacific Ocean to the north through the Priest V alley Strait and to the south through the Santa Maria basin through the end of the Miocen e (Harris, 1987). During the Pliocene the SJB connected to the Pacific Ocean onl y to the north through the Priest Valley Strait (Fig. 6.9). Both the Santa Maria bas in faunas and the Purisima Formation faunas reflect a Lyellian distribution through the Pliocene while the SJB reflects the sea level-driven extinction pattern described by Brett and Baird (1995).

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194 Figure 6.8. Early Pliocene paleogeography of central Californi a at ~5 Ma (modified with annotations from Bowersox, 2004a). Faults wes t of the San Andreas fault are not shown. By this time the Sierra Nevada, San Emigdio Range, Temblor Range, and Diablo Range had been uplifted to near present elevations (Wakabayashi and Sawyer, 2001; Argus and Gordon, 2001). Location of La Honda, Sal inas, Huasna, and Santa Maria Basins are shown relative to the SJB at that time. The modern shoreline and cities locations are shown for reference. Surface and sub surface localities discussed in the text are noted: A – Priest Valley Strait, B – Coalinga, C – Kreyenhagen Hills, D – Kettleman Hills, E – Lost Hills oil field (Kruge, 1983; McGuire et al ., 1983), F – Buttonwillow gas field (Musser, 1938), G – Poso Creek oil field (Weddle, 1959), H – Elk Hills oil field (Berryman, 1973), J – Buena Vista Hills oil field (Tenison, 1989).

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195 of ~15 m and thus silling the SJB. The record from the deepest part of the basin shows continual decrease in paleobathymetry through the P liocene with a short period of rapid paleobathymetric decrease across the boundary of th e Etchegoin and San Joaquin formations (Bowersox, 2004a, fig. 2). Extreme chan ges in environmental conditions are typical of a threshold-regulated marginal basin whe re these changes occur abruptly and have dramatic consequences on the hydrologic, sedim entary, geochemical, and ecological systems inside the basin (Giosan, 2004).Paleosalinity and Paleotemperature Abrupt changes in salinity during periods when a ma rginal basin is isolated from the ocean or during reconnection periods may lead t o reorganizations or collapse of the ecosystem inside the basin (Giosan, 2004). Paleoge ography determined that environmental conditions inside the SJB differed su bstantially from those of the Pacific Coast. Interchange of waters between the SJB and t he open ocean varied due to episodic movement of the San Andreas Fault, variations in th e rate of basin subsidence and sediment infill, and eustasy (Stanton and Dodd, 199 7). In the modern SJB virtually all freshwater enters the basin from the southern Sierr a Nevada (Kratzer and Shelton, 1998) with little entering from the Coast Ranges on the w est (Kratzer and Shelton, 1998) or San Emigdio and southern Temblor Ranges on the south (W ood and Dale, 1964). During the Pliocene six major rivers from southern Sierra Neva da and Diablo Range watersheds flowed into the basin on its eastern and northern m argin (Fig. 6.8). Long, constricted, and shallow-silled channels connecting inland basin s to the ocean act as chokes that reduce or eliminate tidal effects inside the basin and produce a phase lag in water elevation between the inland water body compared to the ocean tide (Kjerfve and Knoppers, 1991; LeBlond, 1991). Thus the narrow an d silled Priest Valley Strait limited tidal height and mixing within and between the oce an and the SJB. Thus the SJB was generally brackish during the Pliocene except for l imited periods during sea-level highstand at ~4.5, 4.2, 3.1, 2.7, 2.5 and 2.4 Ma whe n normal marine salinity prevailed (Fig. 6.9). Isotopically derived paleosalinities ( Stanton and Dodd, 1970, fig. 15; Dodd and Stanton, 1971; Dodd and Stanton, 1975, table 1; Bryant et al., 1995) suggest brackish conditions in the SJB throughout much of the Plioce ne. Paleosalinity of ~25‰ was prevalent in the uppermost Etchegoin Formation (Sta nton and Dodd, 1970, p. 1119) with periods where paleosalinity was <20‰ common through the San Joaquin Formation (Stanton and Dodd, 1970, p. 1119; Dodd and Stanton, 1975, table 1). Modern ocean temperature of the Pacific Coast at th e same latitude as the Coalinga region (Fig. 6.8) is 13.2 C (Loomis, 1988 ). Tropical faunal elements in the Santa Margarita Formation indicate water temperatur es in the SJB were higher than coastal California during the latest Miocene and su b-tropical conditions prevailed (Addicott and Vedder, 1965). Hall (2002, p. 50-52) interpreted this fauna as suggesting that tropical molluscs found in the Santa Margarita Formation were relict of an early Late Miocene warm period restricted to the SJB by favora ble outer tropical biogeographic conditions of Hall (1960, table 2) determined by pa leogeography. Loomis (1988) suggested an average marine temperature of 14.3 C in the Coalinga region during the latest Miocene and Pliocene based on faunal element s of the Santa Margarita Formation and Etchegoin group. Hall (2002, pl. 6b, 8b) inter preted the post-Santa Margarita

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196 Figure 6.9. Comparison of molluscan faunal diversity with rel ative sea-level (modified from Bowersox, 2004a, fig. 3) as total species foun d in average ~200 m stratigraphic intervals in the Jacalitos and Etchegoin Formation and by fauna zone of Woodring et al. (1940) in the San Joaquin Formation. Correlations of biostratigraphic fauna zonules 6-16 of Adegoke (1969) are noted. Intervals of phosphat e deposition (from Fig. 6.8, localities H and J), indicative of upwelling in the basin, are noted with vertical black bars. Interruptions in phosphate deposition and upwelling are coincident with sea-level lowstands and brackish periods in the SJB. Average water temperature (solid line – squares, adapted from Stanton and Dodd, 1970, fig. 5; triangles, this study from Adegoke, 1969, and Loomis, 1990b, using the techniq ue outlined in Loomis, 1990, p. 202-205, and temperature ranges for extant bivalves from Bernard, 1983; Fig. 6.8, locality C) and indicated paleosalinity (dotted lin e – squares, adapted from Stanton and Dodd, 1970, fig. 15; triangles, this study from Ade goke, 1969, and Loomis, 1990b, adapted from techniques in Stanton and Dodd, 1970; Fig. 6.8, locality C) are shown for reference. Peak diversity corresponds with maximum basin flooding suggesting ecological filtering and restriction of potential i mmigrant species from the Pacific Ocean

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197 (Figure 6.9, Continued) through the Priest Valley Strait to those periods with most nearly-marine conditions. Low diversity correspond s to periods of brackish conditions and suggests slowed immigration and exclusion of sp ecies adapted to normal marine conditions. Fauna zones of Woodring et al. (1940) are noted for correlation reference by circled lower-case letters a-g: a upper Etchegoin Formation Patinopecten through 2ndMya zones; bbasal San Joaquin Formation, Cascajo Con glomerate; c lower San Joaquin Formation, Neverita zone; d upper San Joaquin Formation, Pecten zone; e upper San Joaquin Formation, Trachycardium zone; f upper San Joaquin Formation, Acila zone; uppermost San Joaquin Formation, upper Mya zone. Extinction events are noted as circled uppercase letters A-F at major div ersity declines.

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198 Formation paleoclimate of coastal California and th e SJB to be temperate based on 4968% of the fauna indicating temperatures of 10-12 C. However, the faunal composition of the Etchegoin group suggests warmer temperatures inside the SJB and Priest Valley Strait when compared to the correlative and paleoge ographically related cool-water fauna from the coastal Purisima Formation (Powell, 1998). The warmer water inside the SJB (Fig. 6.9) indicates that outer tropical conditions of Hall (1960, table 2) continued through the Early Pliocene and stemmed from the res tricted connection through the Priest Valley Strait to cooler Pacific water inhibiting mi xing with warmer waters of the SJB. Water temperature within the SJB began to decline a fter ~4.5 Ma during deposition of the upper Etchegoin Formation (Fig. 6.9) reaching a thermal minimum coincident with sea-level lowstand at 3.95 Ma (Wornardt et al., 200 1) represented by the basal San Joaquin Formation (Tenison, 1989, fig. 15; Fig. 6.9 fauna zonules 11-13 of Adegoke, 1969). Water temperature showed a general warming trend from ~3.8-3.0 Ma during deposition of the lower to lower upper San Joaquin Formation (Fig. 6.9, fauna zonules 14-15 of Adegoke, 1969). An intense cooling period at ~2.8 Ma (Fig. 6.9) corresponds to a Sierra Nevada glacial advance (Curry, 1966). Aft er ~2.5 Ma, temperatures in the SJB declined (Fig. 6.9, uppermost fauna zonule 15-16 of Adegoke, 1969) in concert with the initiation of northern hemisphere glaciation (Raymo et al., 1989). Circulation, Upwelling, and Productivity Distributions of planktonic foraminifera suggest th at counterclockwise circulation was established in the SJB by latest Early-earliest Middle Miocene (Bandy and Arnal, 1969, p. 802-803). Paleocurrent data from the Etch egoin group in the Coalinga region suggests current flow was dominantly to the south ( Loomis, 1988) indicating that counterclockwise circulation continued during the P liocene. Emery and Csandy (1973) reported that surface-circulation pattern in northe rn hemisphere lakes, marginal seas, estuaries, and lagoons is counterclockwise regardle ss of the direction and duration of winds. Pan et al. (2002) and Laval et al. (2003) r eported this same pattern in their case study of Lake Kinneret, Israel. With an establishe d circulation in the late Neogene SJB, upwelling of bottom waters would have occurred. Un like coastal upwelling, which is controlled by winds and shelf bathymetry, upwelling in the Pliocene SJB would have been caused by the interaction of surface-water cir culation and heating. Pedlosky (2003) modeled circulation driven by heating in a small oc eanic basin connected to the ocean through a narrow passageway and found that mild hea ting of a rotating stratified water body leads to upwelling in the interior of the wate r body. Preserved organic matter in the Monterey and Reef R idge Formation diatomites (Kruge, 1983; McGuire et al., 1983; Graham and Will iams, 1985) is evidence that the silling of the SJB led to anoxia in the deepest par ts of the basin beginning by the Late Miocene (Graham and Williams, 1985, p. 397-398) pe rmitting nutrient-rich waters to occupy the basin (Graham and Williams, 1985). Brow n shales found in the Etchegoin Formation (Musser, 1930; Fig. 6.8, locality F) are indicative of a high preserved organic content and evidence that nutrient-preserving anoxi c conditions continued in the deepest part of the SJB through the Early Pliocene until ~4. 1 Ma. Rapid shallowing of the SJB beginning at ~4.1 Ma and continuing across the Etche goin and San Joaquin formations boundary (Bowersox, 2004a, fig. 2) appears to have ended anoxia as indicated by the

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199 change from brown to green shales across this bound ary (Musser, 1930). Organic-rich sediments containing phosphate, chert, glauconite, and pyrite that are characteristic of deposition in areas of upwelling (Parrish and Curti s, 1982; Baturin, 1983; Parrish, 1983; Parrish and Gautier, 1988) are found throughout the late Neogene deposits in the SJB. Authigenic phosphate nodules reported in the Monter ey and Reef Ridge formations (Kruge, 1983; Graham and Williams,1985, p. 402; Fig 6.8, locality E), phosphate nodules reported in the basal Etchegoin Formation ( Weddle, 1959; Fig. 6.8, locality G), and phosphate nodules, fish remains, glauconite, an d pyrite reported throughout the Etchegoin Formation and in the upper San Joaquin Fo rmation (Berryman, 1973; Fig. 6.8, locality H; Tenison, 1989, fig. 15; Fig. 6.8, local ity J; Fig. 6.9) are suggestive of upwelling in the late Neogene SJB. Sedimentological evidence suggests that upwelling m ay not have been the sole process responsible for phosphate deposition in the late Neogene SJB. Phosphate and glauconite are authigenic minerals that form in oce anographic environments removed from the direct influence of terrigenous sedimentat ion (Loutit et al., 1988). The phosphate nodules found in the thick Late Miocene d iatomite section in the SJB (Kruge, 1983; Graham and Williams,1985, p. 402; Fig. 6.8, l ocality E) are consistent with this observation. Further, during transgressive periods when rising sea-level moves the loci of shallow-water deposits landward, deeper parts of a basin are effectively starved of terrigenous material and authigenic phosphate may b e deposited (Loutit et al., 1988). Rapid sediment deposition on the margin of the SJB during the Early Pliocene, coincident with high sea-levels (Bowersox, 2004a, f igs. 3-4), led to sediment starvation in the central basin and the deposition of phosphat e, glauconite, and pyrite noted by Weddle (1959), Berryman (1973), and Tenison (1989). However, it is not possible to determine the relative contributions of upwelling a nd sediment starvation to phosphate deposition in the late Neogene SJB. High planktic productivity in the latest Miocene Sa n Joaquin Basin is evidenced by deposition of ~900 m of central basinal-facies Re ef Ridge Formation diatomites (Bowersox, 1990, fig. 4; Reid, 1995, fig. 10), coev al with deposition of Sisquoc Formation diatomites in the Santa Maria Basin (Bowe rsox, 1990). Upwelling may have redistributed some nutrients accumulated in the ano xic deep central part of the SJB to shallower water during the late Neogene but this co ntribution cannot be separated from terrestrial runoff in the background nutrient suppl y. More likely, as proposed by Graham and Williams (1985, p. 398, 402-403), is that durin g the Late Miocene nutrient-rich waters from Pacific coastal upwelling entered the S JB through the connecting seaways, circulated counterclockwise around the basin, and r eturned nutrient-depleted waters to the open ocean. Thus, when the current phase of Te mblor Range and southern Coast ranges uplift began ~5.4 Ma (Miller, 1999), the sout hern seaway connection of the SJB to the ocean through the Santa Maria Basin was closed (Harris, 1987), circulation between the Pacific and the SJB was restricted to the Pries t Valley Strait, and the nutrient supply in the basin was substantially reduced. Coincident with the closure of the southern seaway and reduction in the nutrient supply was the end of the overwhelming dominance of SJB diatomite deposition (Graham and Williams, 1 985). Subsequent faunal diversity, and thus peak productivity, is limited to periods o f maximum transgression in the SJB (Fig. 6.9) suggesting a substantial post-Miocene re duction of nutrients to the basin

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200 caused by restricted circulation with the Pacific. Therefore, the nutrient supply fueling productivity in the Pliocene SJB was limited to a b ackground supply from terrestrial runoff, with a possible contribution from upwelling supplemented by an influx nutrients entering the basin through the Priest Valley Strait during periods of maximum transgression.Extinction in the Pliocene SJB In general there are four factors that can cause ex tinction of a taxon: 1.) competition, 2.) predation, 3.) random population f luctuations, and, 4.) habitat alteration (MacArthur, 1972). Each of the first three factors is more likely to lead to the local rather than total extinction of a taxon. Competiti on between species and predation are unlikely causes of extinction (MacArthur, 1972; Men ge and Sutherland, 1987). Random population fluctuations, for example, failure of la rval recruitment for one or more years (Jackson, 1974), are likely and important only when populations are low (MacArthur, 1972). Habitat alteration can directly cause extin ction as well as reduce populations to critically low levels (MacArthur, 1972) catastrophi cally or through longer-term change (Jackson, 1974). A related observation is that geo graphically restricted species are more likely to experience total extinction than widespre ad forms which are more likely to suffer only local extinction (Jackson, 1974; Paulay 1990; Valentine and Jablonski, 1991). Isolation of a marginal basin from the ocea n results in progressive severe environmental deterioration (Caspers, 1957; Giosan, 2004) and many processes, including decreased water salinity, infilling of th e basin by sediments, decrease in vertical circulation and mixing, and bottom-water a noxia, may occur with only partial isolation of the basin (Jackson, 1974). For exampl e, after isolation of the Central European Pannon Basin from the Paratethys and Tethy s in the Late Miocene changes in the hydrological regime caused paleoecological chan ges that led to nearly complete extinction of the restricted marine fauna of the ba sin (Muller, et al., 1999). Such environmental changes severely reduce and change th e composition of the surviving fauna (Jackson, 1974). Temperature and salinity changes are the two proces ses advanced as causing extinction in the Pliocene SJB. Cooling of the SJB was the earliest and most frequently invoked hypothesis for explaining extinctions in th e Etchegoin group (Arnold, 1909; Arnold and Anderson, 1910; Barbat and Galloway, 193 4, p. 490; Loomis, 1990b, p. 222). This hypothesis is similar to the conclusion of Sta nley and Campbell (1981) and Stanley (1986) that Late Pliocene extinction of West Atlant ic faunas was caused when ocean temperatures dropped. Stanley (1986) concluded tha t ocean cooling merely shifted the Late Neogene Northeast Pacific thermally-controlled molluscan provinces southward and did not lead to excessive extinction of Pliocene Pa cific molluscan faunas. Woodring et al. (1940, p. 99-103) suggested gradual freshening of the water due to progressive basin infilling as the cause of extinction in the SJB whi le downplaying the role of possible temperature changes. Much like Woodring et al. (19 40), Adegoke (1969, p. 53) ascribed progressive salinity reduction in the SJB as the pr imary cause behind the faunal changes and argued caution in applying much significance to temperature changes (Adegoke, 1969, p. 62-63). Stanton and Dodd (1975, p. 56) an d Dodd and Stanton (1997, p. 250) suggested that their Ostrea community from the upper San Joaquin Formation was

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201 probably comparable to the Texas Gulf Coast oyster communities described by Parker (1959) where diversity is strongly correlated to sa linity. In fact, during the Pliocene both temperature and salinity decreases generally coinci de with periods of low diversity (Fig. 6.9) and together could appear to be the drives beh ind extinction in the SJB. However, extinction in the SJB had far more complex causatio n. While an enclosed basin may favor recurrent plankto n growth (Adegoke, 1969), productivity collapses appear to have contributed t o late Neogene extinction in the SJB. The large suspension-feeding molluscs of the Santa Margarita Formation were supported by the high planktic productivity of the latest Mio cene (Kirby, 2001). Extinction of these forms at the Santa Margarita-Jacalitos formations c ontact (~5.3 Ma; Fig. 6.9), coincided with an abrupt productivity decline as evidenced by the cessation of diatomite deposition (Graham and Williams, 1985). Low molluscan diversi ty during deposition of the Jacalitos Formation and Etchegoin Formation, during periods of relatively stable temperature and salinity (Fig. 6.9) is symptomatic of low productivity due a lack of nutrients. Peak diversity coincides with maximum t ransgression and drops upon regression(Fig. 6.9, events A-F) enhanced productiv ity due to the increased nutrient supply available during periods of highest sea-leve l. Molluscan diversity plummeted during deposition of the uppermost Etchegoin Format ion (fauna zonule 12 of Adegoke, 1969; Fig. 6.10) suggesting a precipitous decline i n productivity beginning ~4.1 Ma exacerbating effects of increasing brackishness (Fi g. 6.9)and leading to the major extinction event observed at the Etchegoin-San Joaq uin formational boundary at 4.0 Ma (Fig. 6.9, event B). The increase in diversity in the Pecten zone (3.1 Ma; Fig. 6.9) is characterized by many species of large filter-feedi ng bivalves suggesting a brief return of high planktic productivity. The diversity peaks at ~2.4 and 2.3 Ma (Fig. 6.9) are again coincident with high sea-level suggesting productiv ity fueled by the influx of oceanderived nutrients. I interpret a dwarf Dendostrea? vespertina fauna in the uppermost San Joaquin Formation above the Pecten zone, interpreted by Arnold (1909) and Arnold and Anderson (1910) as suggestive of adversely cold-wat er conditions, as also indicative of extremely low salinity (Shimer, 1908) and productiv ity collapse in an increasingly freshwater basin late in the Pliocene history of th e San Joaquin Basin where the nutrient supply from terrestrial runoff was insufficient to support any substantial productivity. The environment inside the Pliocene SJB was control led by the degree of its connection to the Pacific Ocean through the Priest Valley Strait. When it was severed by eustatic lowering and regional tectonic events, com plete loss of connection to the ocean caused the inland sea to become a brackish lake. F our major lithostratigraphic events in the Pliocene SJB are associated with sea level chan ges inside the basin: 1.) deposition of the Etchegoin group followed the global sea-level l owstand at the beginning of the Pliocene; 2.) the Jacalitos and Etchegoin formation s boundary is coincident with a brief sea-level lowstand at ~4.8 Ma (Fig. 6.9) in the midd le of 3rd-order sequence cycle 3.4 (see Bowersox, 2004a, fig. 3) and is suggestive of a short-term tectonic event causing local sea-level change; 3.) the boundary between th e Etchegoin and San Joaquin formations coincides with both the onset of sea-lev el fall (Tenison, 1989, fig. 15; Fig. 6.9), globally reaching lowstand at 3.95 Ma (Wornar dt et al., 2001) in the basal San Joaquin Formation, and uplift of the Coast Range to the west as evidenced by the deposition of the Cascajo Conglomerate at the base of the San Joaquin Formation

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202 Figure 6.10. Diversity of molluscan faunas from the uppermost Etchegoin Formation as species per biostratigraphic zone of Woodring et al (1940) in the Kettleman Hills (Fig. 6.8, locality D) is indicated by the horizontal bar s. Salinity corresponding to each zone is shown by the dotted line with symbols (from Fig. 6. 9). Diversity declined precipitously as the environment deteriorated from the warm, norm al-marine Siphonalia zone to the cooler, brackish Littorina and 2nd Mya zones (Fig. 6.9) with the coincident collapse of productivity following the end of upwelling in the basin. A small rebound in diversity in the Cascajo Conglomerate was a prelude to a long pe riod of low diversity during deposition of the lower San Joaquin Formation (Fig. 6.9). Stratigraphic position is indicated relative to the Etchegoin-San Joaquin con tact.

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203 (Loomis, 1990b; Miller, 1999); and, 4.) the boundar y between the lower and upper San Joaquin Formation coincides with the eustatic lowst and at ~3.2 Ma (Fig. 6.9). Adegoke (1969) noted that composition of the Neogene fauna of the Coalinga region reflected a continuous gradual closing of the SJB. However Sta nton and Dodd (1970, 1972) and Dodd and Stanton (1991) demonstrated ~12 cycles of r elative sea-level changes during deposition of the uppermost Etchegoin and San Joaqu in Formation. Sedimentary cycles recognized by Stanton and Dodd (1970, 1972) and Dod d and Stanton (1991) in the San Joaquin Formation correspond to 3rd-order eustatic events in Figure 6.9. Sea-level lowstands at ~3.2 Ma and ~2.8 Ma (Fig. 6.9) are coinc ident with glaciations recognized in the Sierra Nevada by Curry (1966). High-frequen cy cyclic events in the uppermost Etchegoin Formation (Stanton and Dodd, 1970, 1972; Dodd and Stanton, 1991) do not coincide with the eustatic events in the basin demo nstrated by Bowersox (2004a, fig. 3; Fig. 6.9) suggesting underlying tectonic events (Do dd and Stanton, 1991). Each of these tectonic events may have cut off the Priest Valley Strait from the Pacific Ocean and contributed to the extinction of the marine mollusc faunas during brief brackish periods in the SJB. Two formation boundaries are associate d with regional tectonic events. Lithostratigraphic (Hall and Loomis, 1992) and faun al changes across the boundary between the Jacalitos and Etchegoin Formation sugge st abrupt and tectonically-forced brief relative sea-level lowering inside the SJB. The change from marine rocks of the San Joaquin Formation to freshwater lacustrine depo sits of the overlying Tulare Formation represents the final tectonically forced closing of the Priest Valley Strait during the latest Pliocene at 2.3 Ma. The unique paleogeography and resulting paleoenviro nment of the latest Neogene SJB sets it apart as a subprovince of the larger Ca lifornia coastal Montereyan molluscan province of Stanton and Dodd (1970, fig. 3). Envir onments were much less stable than those of coastal California and were geographically complex resulting in a high rate of speciation, extinction and change (Stanton and Dodd 1997, p. 254). Johnson (1974) defined a perched fauna as one that colonizes an ep icontinental sea during transgression, adapts and becomes stenotopic, thus becoming vulner able to the elimination of their habitat as sea-level declines. Eustatic draining o f epicontinental seas and seaways may eliminate entire subprovinces and provinces causing the extinction of endemic species and possible extinction of stenotopic species of a vanished environment and subsequently forced to live in what now may be a marginal enviro nment for them (Valentine and Jablonski, 1991, p. 6873). Likewise, when the link between a marginal basin and the ocean is severed in response to sea-level fall, ext reme environmental changes may result (Giosan, 2004). The late Neogene faunas inside the SJB were neithe r perched faunas as defined by Johnson (1974) nor stranded faunas in the sense of Paulay (1990). Figure 6.9 shows molluscan diversity and relative sea-level through the Pliocene in the SJB. In this constrained vertical stratigraphic sequence large c hanges in diversity are indicative of immigration and speciation where diversity increase s and extinction where diversity abruptly drops. Following the end-Miocene extincti on there were seven major events in the SJB where >40% of molluscan species became exti nct (Bowersox, 2004b): two extinctions found in the upper Etchegoin Formation at 4.4 and 4.0 Ma (Fig. 6.9, events A-B) and five extinctions in the San Joaquin Format ion at ~3.9, 2.9, 2.6, 2.4, and 2.3 Ma

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204 (Fig. 6.9, events C-F) including the final extincti on coincident with the final tectonic closure of the Priest Valley Strait expressed strat igraphically as the boundary between the San Joaquin and Tulare formations at 2.3 Ma (Fig. 6 .9, event G). In the Pliocene SJB peak molluscan diversity corresponds to periods of highest relative sea-level at ~4.5, 4.2, 3.1, and 2.7 Ma (Fig. 6.9). This suggests that imm igrant species entering the SJB from the Pacific Coast became established during periods of warm climate, normal marine conditions, and high productivity corresponding to maximum basin flooding. Upon glacially driven sea-level fall, the basin became c ooler, more brackish, low productivity, and a marginal environment for those species unable to adapt. Consequently relict faunas from warmer and more normal marine condition s and nearly all immigrants arriving during the highest eustatic levels became extinct. During the extinction event recorded in the uppermost Etchegoin Formation, whic h played-out during deposition of the last 115 m of the formation (Fig. 6.10; ~4.1-4.0 Ma), diversity progressively declined as species adapted to warmer and more normal marine conditions with high productivity became extinct leaving only those species tolerant of cooler, more brackish environments. In Kettleman Hills localities (Fig. 6.8, locality D) the large mactrid Pseudocardium densatum an index fossil of the Etchegoin Formation, is fo und in with normal adult-size specimens in the Siphonalia zone (Fig. 6.10), stunted faunas in the Pseudocardium zone, and is extinct above the Pseudocardium zone. Low-diversity faunas characterize the periods of low sea-level an d initial transgression. This pattern was repeated during each of the major eustatic cycl es affecting the SJB (Fig. 6.9). Following the extinction coincident with the Etcheg oin-San Joaquin formations contact (Fig. 6.9, event B), diversity rebounded slightly d uring deposition of the Cascajo Conglomerate (Fig. 6.10, following event B; Fig. 6. 11). Diversity remained low throughout deposition of the lower San Joaquin Form ation during which paleosalinity remained <20‰ (Stanton and Dodd, 1970, p. 1119; Do dd and Stanton, 1975, table 1). Diversity did not recover until marine flooding pea ked during deposition of the basal upper San Joaquin Formation Pecten zone of Woodring et al. (1940) at ~3.1 Ma (Fig. 6.9). PostPecten zone faunas to extinction event F (Fig. 6.9) are d ominated by Dendostrea? vespertina and Mya arenaria and are characteristic of brackish conditions. Brackish-water diatoms dominate a thin diatomite la yer in the uppermost San Joaquin Formation (Hanna and Grant, 1929). Thus the Priest Valley Strait was not a only a corridor between the Pacific and the SJB but also a filter and ‘trapdoor’. Species unable to adapt to conditions inside the SJB were filtered -out by the strait, whereas those species that adapted to the basin’s environment became trap ped in the basin. The Pliocene history of the SJB is one of environme ntal variability caused by sea level changes due to severing of its tenuous connec tion to the ocean and eustasy. Only the final extinction at San Joaquin-Tulare formatio ns contact (Fig. 6.9, event G) is related to a single cause where the ultimate loss of the ba sin’s connection to the ocean led to the SJB becoming a fresh-water lake and extinction of a ll marine taxa. At the JacalitosEtchegoin contact sea-level fall led to the interru ption of circulation with the ocean, brackishness inside the SJB, and decline in product ivity (Fig. 6.9, ~4.8 Ma). However, although diversity was low during Jacalitos Formati on deposition (Fig. 6.9, ~5.2-4.8 Ma), and remained low during deposition of the lower Etc hegoin Formation (~4.8-4.5 Ma), there was no excess extinction across this formatio n boundary as is seen in the basal San

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205 Figure 6.11A .Proportion of Etchegoin Group faunas comprised of living and extinct bivalves common to coastal faunas. The balance of the faunas in both cases are extinct species endemic to the SJB. Extinct species comprise ~50% of the coastal species found in the Jacalitos and Etchegoin formations faunas an d ~33% of those in the San Joaquin Formation fauna.

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206 Figure 6.11B. Proportion of Etchegoin Group faunas composed of living and extinct coastal fauna gastropods. The extinct portion of t he faunas increases during the Pliocene while the endemic portion appears to have decreased

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207 Joaquin Formation (Fig. 6.9, event C). Thus bracki sh conditions and low productivity together were not sufficient to cause excessive ext inction. Major extinction events in the Pliocene SJB followed brief periods of immigration and diversification at eustatic highstands then the onset of brackish conditions, c ooling, and productivity collapse driven by regression (Fig. 6.9, events A-F). These three controls affected different members of the faunas: 1). species adapted to norma l marine conditions, including both bivalves and all predatory gastropods, became extin ct as conditions became brackish, 2.) cooling led to extinction of warm-water species, an d, 3). productivity collapse led to extinction of the large bivalves. Thus, abrupt reg ression-driven hydrologic change, productivity collapse from coincident geochemical a nd sedimentary change, and climatic change led to the major extinction events in the Pl iocene SJB. Biogeography of California Late Neogene Molluscan F aunas The portion of Etchegoin group faunas composed of s pecies occurring in coastal faunas is shown in Figure 6.11. Extinct species fo und in both coastal and SJB bivalve faunas comprise ~50% of the Jacalitos and Etchegoin formations faunas and ~33% of those in the San Joaquin Formation fauna (Fig. 6.11 A). Because the extant portion of each three formations’ faunas is about equal, the l arger proportion of extinct bivalve species found only in the San Joaquin Formation fau na suggests an increase in bivalve endemism in the SJB during the Late Pliocene. The total proportion of gastropod species found in both coastal and SJB faunas increased from ~40% of the Jacalitos Formation fauna to ~60% of the Etchegoin Formation fauna (Fig. 6.11B) suggesting an Early Pliocene immigration of gastropods to the SJB. How ever the extinct portion of the faunas increases during the Pliocene which suggests a largely unsuccessful adaptation of coastal gastropods to the SJB environment. Figure 12 examines the endemic portion of the Etchegoin group faunas and its contribution to extinction in the SJB. The endemic portion of bivalve faunas increased from 9% of the Jacalitos Formation fauna to 12% of the Etchegoin Formation fauna and then doubled to 2 4% of the San Joaquin Formation fauna (Fig. 6.12A). This suggests that increasing restriction from the Pacific Ocean during the Pliocene either filtered and limited imm igration of coastal bivalve species into the SJB to those opportunistic species best able to adapt to the environment inside the basin or evolution inside the basin. Timing of the speciation event at the Etchegoin-San Joaquin contact suggests diversification of the few surviving Early Pliocene bivalve populations into those habitats previously occupied by newly extinct species and habitats newly created with changed environmental conditions Stanton and Dodd (1997) concluded that species restricted to the Pecten zone evolved from Pacific coastal stock that colonized the SJB during eustatic sea-level ri se (Fig. 6.9) The absence of these taxa outside the SJB and their first occurrences near th e base of the Pecten zone indicate evolution within a geologically short time span fol lowing basin flooding (Stanton and Dodd, 1997). The portion of basinally-endemic Etch egoin group gastropod faunas declined steadily through the Pliocene (Fig. 6.12B) Approximately ~25% of endemic species in the Jacalitos fauna and ~50% of those in the San Joaquin fauna are stratigraphically restricted to these units. The p ortion of formationally-endemic species in SJB gastropod faunas was greatest following the extinction events at the Santa Margarita-Jacalitos contact (~5.3 Ma; Fig. 6.9) and Etchegoin-San Joaquin contact (4.0

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208 Figure 6.12A. Endemic portion of bivalve faunas. Endemic portion of the Etchegoin Group faunas illustrating the contribution of endem ism to extinction in the SJB. Paleogeography (Figure 8) dictated that all endemic species would become extinct. Endemic species increased from 9% of the Jacalitos fauna to 12% of the Etchegoin fauna but then doubled to 24% of the San Joaquin fauna. This suggests that increasing restriction from the Pacific Ocean during the Plioc ene had an impact on Late Pliocene bivalve speciation in the SJB.

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209 Figure 6.12B. Endemic portion of gastropod faunas. The portion of basinally-endemic Etchegoin Group gastropod faunas declined steadily through the Pliocene. The portion of formationally-endemic species in SJB faunas was greatest following eustatic events (Figure 10). ~25% of endemic species in the Jacalito s fauna and half of those in the San Joaquin fauna are restricted to these formations.

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210 Table 6.4. Extant species in correlative coastal and San Joa quin Basin faunas.

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211 Ma; Fig. 6.9, event B) when the availability of une xploited or under-exploited habitats was greatest. Local environmental conditions led t o stenotopy of species arising in the SJB and precluded range expansion through the Pries t Valley Strait into the Pacific Ocean thus limiting their biogeographic range by th eir own adaptive success. Thus, the general term “trapdoor fauna” applies to faunas dev eloped by immigrant species passing through an adaptive filter, entering a restricted b asin, adapting and diversifying, then the new fauna being unable to expand back through the r estriction into the environment of its ancestral range. Thus for a trapdoor fauna, endemi sm following from adaptive success and species diversification in a marginal basin may become an incipient extinction event. As a final note, this discussion of Late Neogene ex tinction has included two extant faunas: a fauna comprising the species prese ntly living in coastal California waters and a fauna of those extant species found in the Pl iocene fossil record of California. The quality of the California Pliocene fossil record is illustrated in Figure 6.13. The Etchegoin group faunas include a total of 48 extant bivalve and 23 extant gastropod species. In the faunas from the Santa Maria Basin and Purisima Formation (Fig. 6.7), those most closely associated by palaeogeography to the Late Neogene SJB, at best ~50% of the extant species found in the correlative Etchegoin group faunas (Fig. 6.2) are found in either fauna. Geographic preferences of s ome species are noted by fewer extant species occurring in both the southerly Santa Maria Basin and northerly Purisima Formation faunas than in either fauna individually. Expanding this comparison to include all of the Pliocene faunas reviewed in this paper shows 73% of extant species found in the Jacalitos Formation fauna, 57% of exta nt species found in the Etchegoin Formation fauna, and 87% of extant species found in the San Joaquin Formation fauna are found in any correlative coastal fauna. Overal l, only 69% of all extant species found in Etchegoin group faunas are found in any correlat ive Pliocene fauna from the California coast. Because all species within the S JB eventually became extinct, the 31% of extant species known only from the Pliocene foss il record of the SJB must have an incomplete fossil record since the only way these s pecies could have survived to the present is to also have lived on the California coa st. Considering the number and wide geographic distribution of faunas reviewed in this paper (Fig.1), arguments of ecological preferences, sample bias, taphonomic removal, or si mple misidentification do not adequately explain the absence of extant species fo und in Etchegoin group faunas from the correlative coastal faunas. Valentine (1989) o btained similar results in his study of the California fossil record where 77% of extant sp ecies are not known to be represented in Pleistocene faunas. This also suggests that som e portion of the endemic species attributed to the Etchegoin group (Fig. 6.13) may b e artifacts of the incomplete fossil record of coastal California Pliocene faunas. Howe ver, although the coastal faunas reviewed in this paper are a representative sample of the California fossil record, they did not stem from an exhaustive search of the literatur e. Where these “missing” species occur in coastal Pliocene faunas requires a still d eeper literature search, further review of existing collections, additional sampling of known faunas, and discovering of new faunas though the California fossil record may ultimately prove inadequate to resolve this question.

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212 Figure 6.13A. Extant bivalves in Etchegoin group faunas and the ir occurrences in coastal California faunas. These two charts (Fig. 6.13A-6.13B) illustrate the poverty of the California Pliocene fossil record. The Santa M aria Basin and Purisima Formation were most closely linked by paleogeography to the P liocene SJB (Figure 8). The bar labeled “Any Coastal Fauna” includes all correlativ e faunas reviewed in this paper. At best, ~90% of the extant species found in Etchegoin Group faunas have been found in other California Pliocene faunas. Geographic range s of species are illustrated by occurrences in either the Santa Maria Basin, Purisi ma Formation, or both. a) Extant bivalve species in Etchegoin Group faunas and their occurrences in coastal California faunas.

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213 Figure 6.13B. Extant gastropod species in Etchegoin Group faunas and their occurrences in coastal California faunas. No extan t gastropod species found in the Jacalitos fauna occurs in the correlative Santa Mar ia Basin fauna.

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214 Conclusions1.An average of 61% of Pliocene molluscan species, 64% of bivalves and 58% of gastropods, found in 15 Pacific coastal California faunas are extant. However, the extinction of molluscs in the Pliocene Etchegoin gr oup of the SJB averaged nearly twice that of coastal California and is comparable to Late Pliocene extinction of Western Atlantic and Gulf of Mexico mollusc populat ions. In faunas from the Pliocene Etchegoin group only 34% of molluscs, 40% of bivalves and 21% of gastropods, are extant. 2.The Pliocene SJB was a shallow inland sea connect ed on the northwest to the Pacific Ocean by a narrow silled strait that was both a fil ter and a trapdoor for faunal elements entering the basin from the Pacific. With in the SJB conditions were warmer and brackish throughout much of the Pliocene limiti ng immigration of normal marine species from the Pacific to periods of highest eust atic levels. Consequently, recovery of diversity after an extinction event was slow. 3.Timing of the two major molluscan extinctions in the upper Etchegoin Formation at ~4.4 and 4.0 Ma and the three in the upper San Joaqu in Formation at ~3.9, 2.9, and 2.6 Ma coincide with eustatic drawdown and the deve lopment of brackish conditions. 4.Progressive diversity decline during the uppermos t Etchegoin extinction at ~4.1-4.0 Ma demonstrates increasingly brackish conditions as sea-level fell and suggests the onset of a long-term productivity collapse lasting until the beginning of the upper San Joaquin Formation at ~3.1 Ma contributing to extinct ion in the Pliocene SJB. 5.Increasing restriction from the Pacific Ocean dur ing the Pliocene filtered and limited immigration of coastal species into the SJB to thos e opportunistic species best able to adapt to the environment inside the basin. Timing of the speciation events suggest diversification of surviving Early Pliocene mollusc faunas into the unexploited and under-exploited and habitats newly created with cha nged environmental conditions. 6.Adaptation, stenotopy, and diversification of spe cies to local environmental conditions inside the SJB precluded range expansion back through the Priest Valley Strait into the Pacific Ocean. 7.Major extinction events in the Pliocene SJB abrup tly followed eustatic highstands and the onset of brackish conditions, cooling, and productivity collapse due to climatic changes and regression-driven hydrologic, geochemical and sedimentary changes. 8.Only 69% of extant mollusc species found in Plioc ene Etchegoin group faunas from the SJB are found in the coastal California Pliocen e fossil record despite the number and wide geographic distribution of faunas reviewed in this paper. Those extant species known only from the Pliocene fossil record of the SJB must have an incomplete fossil record since the only way these s pecies could have survived to the present is to also have lived on the California coa st. This suggests that there also may be fewer endemic species than are apparently found in Etchegoin group faunas due to an incomplete fossil record of coastal California P liocene faunas. ReferencesAddicott, W.O., 1965, Some western American Cenozoi c gastropods of the genus Nassarius: United States Geological Survey Professi onal Paper 503-B, 23 p.

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222 Nomland, J.O., 1917a, The Etchegoin Pliocene of mid dle California: University of California Publications in Geology, v. 10, p. 191-2 54. Nomland, J.O., 1917b, Fauna of the Santa Margarita beds in the north Coalinga region of California: University of California Publications i n Geology, v. 10, p. 293-326. Packard, E.L., 1918, Molluscan fauna from San Franc isco Bay: University of California Publications in Zoology, v. 14, p. 199-452. Pan, H., Avissar, R. and Haidvogel, D.B., 2002, Sum mer circulation and temperature structure of Lake Kinneret: Journal of Physical Oce anography, v. 32, p. 295-313. Parker, R.H., 1959, Macroinvertebrate assemblages o f central Texas coastal bays and Laguna Madre: American Association of Petroleum Geo logists Bulletin, v. 43, p. 2100-2166. Parrish, J.T., 1983, Upwelling deposits: nature of association of organic-rich rock, chert, chalk, phosphorite, and glauconite [abstract]: Amer ican Association of Petroleum Geologists Bulletin, v. 67, p. 529. Parrish, J.T. and Curtis, R.L., 1982, Atmospheric c irculation, upwelling, and organic rich rocks in the Mesozoic and Cenozoic eras: Palaeogeog raphy, Palaeoclimatology, Palaeoecology, v. 40, p. 31-66. Parrish, J.T. and Gautier, D.L., 1988, Upwelling in Cretaceous Western Interior Seaway: Sharon Springs Member, Pierre Shale [abstract]: Ame rican Association of Petroleum Geologists Bulletin, v. 72, p. 232-233. Paulay, G., 1990, Effects of late Cenozoic sea-leve l fluctuations on the bivalve faunas of tropical oceanic islands: Paleobiology, v. 16, p. 4 15-434. Pedlosky, J., 2003, Thermally driven circulations i n small oceanic basins: Journal of Physical Oceanography, v. 33, p. 2333-2340. Perkins, J.A., 1987, Provenance of the Upper Miocen e and Pliocene Etchegoin Formation: Implications for Paleogeography of the L ate Miocene of Central California: United States Geological Survey Open-fi le Report 87-167, 86 p. Peterson, C.H., 1982, The importance of predation a nd intraand interspecific competition in the population biology of two infaun al suspension-feeding bivalves, Protothaca staminea and Chione undatella : Ecological Monographs, v. 52, p. 437475. Peterson, C.H. and Andre, S.V., 1980, An experiment al analysis of interspecific competition among marine filter feeders in a soft-s ediment environment: Ecology, v. 61, p. 129-139. Powell, C.L., 1998, The Purisima Formation and Rela ted Rocks (Upper MiocenePliocene), Greater San Francisco Bay Area, Central California Review of Literature and United States Geological Survey Collection (now Housed at the Museum of Paleontology, University of California, Berkeley): United States Geological Survey, Open File Report 98-594, 101 p. Powell, C.L. and Stevens, D., 2000, Age and Paleoen vironmental Significance of Megainvertebrates From the "San Pedro" Formation in the Coyote Hills, Fullerton and Buena Park, Orange County, Southern California: Uni ted States Geological Survey, Open File Report 00-319, 83 p. Preston, H.M., 1931, Report of Fruitvale oil field: Summary of Operations, California Oil Fields, v. 16, p. 5-24.

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223 Raymo, M.E., Ruddiman, W.F., Backman, J., Clement, B.M. and Martinson, F.G., 1989, Late Pliocene variation in northern hemisphere ice sheets and North Atlantic deep water circulation: Paleoceanography, v. 4, p. 413-4 46. Reid, S.A., 1995, Miocene and Pliocene depositional systems of the southern San Joaquin Basin and formation of sandstone reservoirs in the Elk Hills area, California, in Fritsche, E.A., ed., Cenozoic Paleogeography of the Western United States II: Society of Economic Paleontologists and Mineralogis ts, Pacific Section, Book 75, p. 131-150. Reinhart, P.W., 1943, Mesozoic and Cenozoic Arcidae from the Pacific Slope of North America. Geological Society of America Special Pape r 57, 117 p. Rose, R.L. and Colburn, I.P., 1963, Geology of the east-central part of the Priest Valley quadrangle, California, Geology of Salinas Valley and the San Andreas Fault: American Association of Petroleum Geologists and So ciety of Economic Paleontologists and Mineralogists, Pacific Sections Annual Spring Field Trip 1963 Guidebook, p. 38-45. Roth, B., 1979, Late Cenozoic marine invertebrates from northwest California and southwest Oregon. PhD thesis, University of Califor nia, Berkeley, California, 803 pp. Rowland, R.W., 1972, Paleontology and paleoecology of the San Diego Formation in northwestern Baja California: Transactions of the S an Diego Society of Natural History, v. 17, p. 25-32. Sarna-Wojcicki, A.M., Bowman, H.W. and Russell, P.C ., 1979, Chemical Correlation of Some Late Cenozoic Tuffs of Northern and Central Ca lifornia by Neutron Activation Analysis of Glass and Comparison with X-ray Fluores cence Analysis: United States Geological Survey Professional Paper 1147, 15 p. Scott, P.V. and Blake, J.A., 1998, Taxonomic Atlas of the Benthic Fauna of the Santa Maria Basin and Western Santa Barbara Channel, Volu me 8 – the Mollusca Part 1: Santa Barbara, California, Santa Barbara Museum of Natural History, Santa Barbara, California, 250 p. Shimer, H.W., 1908, Dwarf faunas: American Naturali st, v. 42, p. 472-490. Stanley, S.M., 1984, Temperature and biotic crises in the marine realm: Geology, v. 12, p. 205-208. Stanley, S.M., 1986, Anatomy of a regional mass ext inction: Plio-Pleistocene decimation of the Western Atlantic bivalve fauna: Palaios, v. 1, p. 17-36. Stanley, S.M., Addicott, W.O. and Chinzei, K., 1980 Lyellian curves in paleontology: possibilities and limitations: Geology, v. 8, p. 42 2-426. Stanley, S.M. and Campbell, L.D., 1981, Neogene mas s extinction of Western Atlantic molluscs: Nature, v. 293, p. 457-459. Stanton, R.J., 1966, Megafauna of the upper Miocene Castaic Formation, Los Angeles County, California: Journal of Paleontology, v. 40, p. 21-40. Stanton, R.J. and Dodd, J.R., 1970, Paleoecologic t echniques – comparison of faunal and geochemical analysis of Pliocene paleoenvironments, Kettleman Hills, California: Journal of Paleontology, v. 44, p. 1092-1121.

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224 Stanton, R.J. and Dodd, J.R., 1972, Pliocene cyclic sedimentation in the Kettleman Hills, California in Rennie, E.W., ed., Guidebook to Geolo gy and Oil Fields, West Side Central San Joaquin Valley: American Association of Petroleum Geologists, Pacific Section, p. 50-58. Stanton, R.J., and Dodd, 1976, Pliocene biostratigr aphy and depositional environment of the Jacalitos Canyon area, California, in Fritsche, E.E., Ter Best, H., and Wornardt, W.W., eds., The Neogene Symposium: Society of Econo mic Paleontologists and Mineralogists, Pacific Section, p. 85-94. Stanton, R.J. and Dodd, J.R., 1997, Lack of stasis in late Cenozoic marine faunas and communities, central California: Lethaia, v. 30, p. 239-256. Stewart, R.E., and Stewart, K.C., 1949, Local relat ionships of the Mollusca Wildcat coast section, Humboldt County, California, with related data on the Foraminifera and Ostracoda: State of Oregon department of Mineral In dustries Bulletin, v. 36, no. 8, p. 168-208. Tenison, J.A., 1989, Biostratigraphy, lithostratigr aphy and paleoenvironment of the Etchegoin and San Joaquin Formations, Buena Vista H ills, California [MS thesis]: Austin, Texas, University of Texas, 125 p. Turgeon, D.D., Bogan, A.E., Coan, E.V., Emerson, W. K., Lyons, W.G., Pratt, W.L., Roper, C.F.E., Scheltema, A., Thompson, F.G. and Wi lliams, J.D., 1988, Common and Scientific Names of Aquatic Invertebrates from the United States and Canada – Mollusks: Bethesda, Maryland, American Fisheries So ciety, 277 p. Valentine, J.W., 1958. Late Pleistocene megafauna o f Cayucos, California, and its zoogeographic significance: Journal of Paleontology v. 32, p. 687-696. Valentine, J.W., 1989, How good was the fossil reco rd? Clues from the California Pleistocene. Paleobiology, v. 15, p. 83-94. Valentine, J.W. and Jablonski, D., 1991, Biotic eff ects of sea level change; the Pleistocene test: Journal of Geophysical Research, B, Solid Earth and Planets, v. 96, p. 6873-6878. Wagner, H.M., Riney, B.O., Demre, T.A. and Prother o, D.R., 2001, Magnetic stratigraphy and land mammal biochronology of the n onmarine facies of the Pliocene San Diego Formation, San Diego County, California, Prothero, D.R., ed., Magnetic Stratigraphy of the Pacific Coast Cenozoic: SEPM So ciety for Sedimentary Geology, Pacific Section, Book 91, p. 359-368. Wakabayashi, J. and Sawyer, T.L., 2001, Stream inci sion, tectonics, uplift, and evolution of topography of the Sierra Nevada, California: Jou rnal of Geology, v. 109, p. 539562. Weddle, J.R., 1959, Premier and Enas areas of Poso Creek oil field. Summary of Operations, California Oil Fields, v. 45, no. 2, p. 41-50. Whittlesey, K.E., 1998. Barnacles or Mudstickers? The Paleobiology, Paleoecology, and Stratigraphic Significance of Tamiosoma gregaria in the Pancho Rico Formation, Salinas Valley, California [MS thesis]: Los Angeles California, University of Southern California, 218 p. Wood, P.R. and Dale, R.H., 1964, Geology and ground -water features of the EdisonMaricopa area, Kern County, California: United Stat es Geological Survey Water Supply Paper 1656, 108 p.

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225 Woodring, W.P. and Bramlette, M.N., 1950, Geology a nd Paleontology of the Santa Maria District, California: United States Geologica l Survey Professional Paper 222, 185 p. Woodring, W.P., Stewart, R. and Richards, R.W., 194 0, Geology of the Kettleman Hills Oil Field, California: United States Geological Sur vey Professional Paper 195, 170 p. Wornardt, W.W., and Vail, P.R., 1991, Revision of t he Plio-Pleistocene cycles and their application to sequence stratigraphy and shelf and slope sediments in the Gulf of Mexico: Transactions of the Gulf Coast Association of Geological Societies, v. 41, p. 719-744. Wornardt, W.W., Shaffer, B. and Vail, P.R., 2001, R evision of the Late Miocene, Pliocene, and Pleistocene sequence cycles [abstract ]: American Association of Petroleum Geologists Bulletin, v. 85, p. 1710. Yerkes, R.F., 1972, Geology and Oil Resources of th e Western Puente Hills Area, Southern California: United States Geological Surve y Professional Paper 420-C, 63 p.

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Appendix A

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Locality NumberMap 7 Topographic QuadrangleCoordinates1SecT/R2NotesRemarks 051599.012,3La Cima1550 FSL 1300 FWL 3521S/17E 051599.022,3La Cima180 FNL 390 FSL 1022S/17Earesampled as locality 111700.01 100299.011Domengine Ranch290 FSL 1090 FWL 1219S/15E uppermost Etchegoin Formation, locality B6548 of Adegoke (1969) 100299.021Coalinga 2380 FNL 40 FWL 3419S/15E 100700.003La Cima 100 FSL 1400 FWL 1222S/17Eafloat from locality 021701.01 100700.013La Cima 850 FSL 1060 FWL 1222S/17E 100700.023La Cima 1000 FSL 890 FWL 1222S/17E 100700.033La Cima 1000 FSL 890 FWL 1222S/17E 100700.043La Cima 1050 FSL 900 FWL 1222S/17E 8 m east of 100700.03, base of sand 100700.04a3La Cima 1050 FSL 900 FWL 1222S/17E 8 m east of 100700.03, top of sand 111700.012,3La Cima180 FNL 390 FEL 1022S/17E resample of locality 051599.02 111800.01a3La Cima 390 FNL 1300 FWL 1322S/17E

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Locality NumberMap 7 Topographic QuadrangleCoordinates1SecT/R2NotesRemarks 111800.01b3La Cima 390 FNL 1300 FWL 1322S/17E 111800.01c3La Cima 390 FNL 1300 FWL 1322S/17E 111800.023La Cima 1150 FSL 670 FWL 1222S/17E 111800.033La Cima 1120 FSL 1400 FEL 1222S/17E 121500.01x3La Cima 2690 FNL 1100 FWL 1222S/17E 121500.01a3La Cima 2690 FNL 1100 FWL 1222S/17E 121500.01b3La Cima 2690 FNL 1100FWL 1222S/17E 121500.02a3La Cima 2400 FNL 800 FWL 1222S/17E 121500.02b3La Cima 2400 FNL 800 FWL 1222S/17E 121500.02c3La Cima 2400 FNL 800 FWL 1222S/17E 121500.033La Cima 2400 FNL 1360 FWL 1222S/17E 021701.013La Cima 250 FSL 1300 FWL 1222S/17E

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Locality NumberMap 7 Topographic QuadrangleCoordinates1SecT/R2NotesRemarks 021701.023La Cima 2000 FNL 800 FWL 1222S/17E 060701.0111West Elk Hills2450 FSL 100 FWL 2830S/22E 061001.016Los Viejos 250 FNL 30 FWL 3423S/19E Upper Mya zone of Woodring et al (1940) 101301.01a3La Cima 850 FNL 2430 FWL 1122S/17E locality 242 of Woodring et al (1940) 101301.01b3La Cima 850 FNL 2430 FWL 1122S/17E 101301.01c3La Cima 850 FNL 2430 FWL 1122S/17E 101301.02a2,3La Cima 1680 FSL 1580 FWL 222S/17E between localities 257a and 2 of Woodring et al (1940) 101301.02b2,3La Cima 1680 FSL 1580 FWL 222S/17E 101301.033La Cima 2150 FNL 1250 FEL 222S/17E locality 250 of Woodring et al (1940) 101301.043La Cima 1160 FNL 2660 FEL 1322S/17E locality 240 of Woodring et al (1940) 101301.05a-b3La Cima1850 FSL 2330 FWL 722S/18E locality 300a of Woodring et al (1940) 101301.063,4La Cima800 FNL 50 FEL 722S/18E locality 156 of Woodring et al (1940)

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Locality NumberMap 7 Topographic QuadrangleCoordinates1SecT/R2NotesRemarks 101301.074La Cima 800 FSL 2320 FEL 1722S/18E locality 284 of Woodring et al (1940) 101301.08a4La Cima 2400 FSL 1380 FWL 1622S/18E 101301.08b4La Cima 2400 FSL 1380 FWL 1622S/18E 2.9 m above locality 101301.08a 101301.08c4La Cima 2400 FSL 1380 FWL 1622S/18E 0.8 m above locality 101301.08b 101301.08d4La Cima 2400 FSL 1380 FWL 1622S/18E 1.1 m above locality 101301.08c 121401.01a1Coalinga 3860 FSL 1320 FEL 2619S/15E from road cut on North side of highway 121401.01b1Coalinga 3860 FSL 1320 FEL 2619S/15E from bed below locality 121401.01a 121401.021Coalinga 2030 FSL 350 FWL 3419S/15Eamussel-giant barnacle bioherm 121401.031Coalinga 2150 FSL 550 FWL 3419S/15E locality B6543 of Adegoke (1969) 030202.01a4La Cima 1800 FNL 900 FEL 1622S/18EaSan Joaquin Formation, tuff, sampled 0.7 m above base 030202.01b4La Cima 1800 FNL 900 FEL 1622S/18Ec,dSan Joaquin Formation, tuff, sampled 1. 3 m above base 030202.01c4La Cima 1800 FNL 900 FEL 1622S/18EaSan Joaquin Formation, tuff, sampled 2.5 m above base

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Locality NumberMap 7 Topographic QuadrangleCoordinates1SecT/R2NotesRemarks 030202.024La Cima 2690 FNL 1900 FWL 1622S/18EbEtchegoin Formation 030202.034La Cima 400 FNL 1250 FWL 1722S/18EbEtchegoin Formation 030202.043,4La Cima870 FSL 1160 FWL 822S/18EbEtchegoin Formation 030202.053,4La Cima1600 FSL 690 FWL 822S/18Ec,dEtchegoin Formation, 0.6 m tuff; three samples 030202.063La Cima 950 FSL 2390 FWL 722S/18E photographed 02 March 2002; collected 29 May 2002 030202.073La Cima 1100 FSL 260 FEL 722S/18Ea,cEtchegoin Formation tuff, sampled 1.1 m above base 030202.083La Cima 1100 FSL 260 FEL 722S/18Ea,cEtchegoin Formation tuff, sampled 1.7 m above base 030202.093La Cima 1140 FSL 190 FEL 722S/18Ea,cEtchegoin Formation tuff, sampled ~5 m North of locality 030202.08 030202.105Los Viejos 1400 FNL 110 FWL 623S/19Easample from above locality 143 of Woodring et al (1940); barren 030202.115Los Viejos 1400 FNL 110 FWL 623S/19Ea2 m below locality 030202.10; barren 052802.013La Cima 400 FNL 700 FWL 1222S/17EbEtchegoin Formation; photographed only 052802.024La Cima 1750 FNL 2330 FWL 2022S/18Eamussel-giant barnacle bioherm

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Locality NumberMap 7 Topographic QuadrangleCoordinates1SecT/R2NotesRemarks 052802.034La Cima 1660 FNL 2320 FEL 2022S/18E ~30 m South of locality 052802.02 052802.03a4La Cima 1660 FNL 2320 FEL 2022S/18E duplicate sample from locality 052802.03 052802.044La Cima 1580 FNL 2600 FEL 2022S/18E ~30 m North of locality 052802.02 052802.054La Cima 1530 FNL 1320 FWL 2022S/18E in road cut 1.7 m above road level 052802.06a4La Cima 1530 FNL 1320 FWL 2022S/18E top of road cut, West end 052802.06b4La Cima 1530 FNL 1320 FWL 2022S/18E ~15 m East of locality 052802.06a 052802.074Kettleman Plain750 FSL 1150 FWL 2122S/18E 052802.08a-d4La Cima430 FNL 1390 FEL 2122S/18EcEtchegoin formation, 2.2 m tuff bed; too fine grain for 40Ar/39Ar dating 052802.095Los Viejos 700 FSL 2650 FEL 3622S/18E float from ground squirrel burrow 052802.105Los Viejos 650 FSL 2550 FEL 3622S/18Eafloat on hillside, stratigraphic interval unknown 052902.014La Cima 950 FSL 1190 FWL 1022S/18EaTulare Formation 052902.024La Cima 690 FNL 640 FEL 822S/18EaTulare Formation, lower Amnicola zone of Woodring et al (1940)

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Locality NumberMap 7 Topographic QuadrangleCoordinates1SecT/R2NotesRemarks 052902.033La Cima 1000 FSL 560 FEL 622S/18Eabed of small echinoids 052002.043La Cima 850 FSL 410 FEL 622S/18E Pecten zone of Woodring et al (1940) 053002.01a7Santa Rita Peak2020 FNL 1150 FEL 2419S/13E west end of road cut on North side of Los Gatos Creek Road 053002.01b7Santa Rita Peak2020 FNL 1150 FEL 2419S/13E 1.5 m East and 0.5 m above locality 053002.01a 053002.01c7Santa Rita Peak2020 FNL 1150 FEL 2419S/13E 3.7 m East of locality 053002.01b 053002.027San Benito Mountain250 FSL 1200 FWL 1319S/12E 0.7 m West of locality 053002.01a 053002.038Priest Valley 2400 FNL 1260 FWL 2620S/12EaCascajo Conglomerate, vertical bed 053002.048Priest Valley 2080 FSL 2300 FEL 2620S/12Earecovered one internal mold of Mya arenaria 053102.0112Eagles Rest Peak3570 FNL 480 FEL 510N/22Wshell bed dips 50/N50W 110702.011Domengine Ranch2300 FSL 2270 FEL 1519S/15E 4.5 m above locality 110702.02; locality B6532 of Adegoke (1969) 110702.021Domengine Ranch2300 FSL 2270 FEL 1519S/15E 1.5 m above locality 110702.03; locality B6531 0f Adegoke (1969) 110702.031Domengine Ranch2300 FSL 2270 FEL 1519S/15E locality B6530 of Adegoke (1969)

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Locality NumberMap 7 Topographic QuadrangleCoordinates1SecT/R2NotesRemarks 110702.041Domengine Ranch2200 FNL 2080 FEL 1519S/15Eb Crassostrea titan bioherm near top of Santa Margarita Formation 110702.051Domengine Ranch2200 FSL 2200 FWL 1519S/15E Santa Margarita Formation sample for microfossils; barren 110702.061Coalinga 1520 FSL 1020 FWL 3419S/15E locality B6544-B6546 of Adegoke (1969) 110702.071Coalinga 1210 FSL 1050 FWL 3419S/15E mussel-giant barnacle bioherm 110702.081Coalinga 960 FSL 1180 FEL 3419S/15E 0.9 m below top of Etchegoin Formation 110702.092Avenal 2300 FSL 1070 FEL 2821S/17E float from Pecten zone of Woodring et al (1940) 110702.102Avenal 1140FNL 2150 FEL 2821S/17E locality 56 of Woodring et al (1940) 110802.019Garza Peak 250 FSL 700 FEL 723S/17EaLate Miocene Monterey Formation; chert 110802.029Garza Peak 800 FSL 1050 FEL 723S/17EaLate Miocene Reef Ridge Formation; siltstone, barren 110802.039Garza Peak 1640 FSL 1500 FEL 723S/17EaJacalitos Formation; barren 110802.049Garza Peak 2030 FNL 1130 FWL 723S/17E locality 12-30-88-5 of Loomis (1990b)

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Locality NumberMap 7 Topographic QuadrangleCoordinates1SecT/R2NotesRemarks 110802.059Garza Peak 1660 FNL 2090 FWL 723S/17E float from locality D1109 of Adegoke (1969) 110802.069Garza Peak 1660 FNL 2090 FWL 723S/17Eafloat from middle Miocene Temblor Formation 110802.079Garza Peak 1660 FNL 2090 FWL 723S/17Eafloat from middle Miocene Temblor Formation 052303.0110Carneros Rocks2300 FSL 2390 FEL 1028S/20EaReef Ridge Formation; diatomite 052303.01a10Carneros Rocks2300 FSL 2390 FEL 1028S/20Ea10 m North of locality 052303.01, float from Etchegoin Formation 052303.0210Carneros Rocks2250 FSL 2050 FWL 1028S/20Eafloat from Reef Ridge Formation; chert 052303.0310Carneros Rocks2310 FNL 2040 FWL 1028S/20Eafloat from Reef Ridge Formation; chert 052303.0410Carneros Rocks1090 FNL 800 FWL 1028S/20Eafloat Etchegoin Formation; barren 052704.019Garza Peak 590 FNL 1690 FWL 723S/17E locality D1115 of Adegoke (1969) (in part) 052704.029Garza Peak 590 FNL 1690 FWL 723S/17E locality D1115 of Adegoke (1969) (in part) 052704.039Garza Peak 1340 FNL 1860 FWL 723S/17E 3.0 m outcrop of echinoid fragments and mollusc fragments coquina 052704.049Garza Peak 600 FNL 1750 FEL 723S/17E 0.6 m oyster-giant barnacle bioherm

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Locality NumberMap 7 Topographic QuadrangleCoordinates1SecT/R2NotesRemarks 052704.059Garza Peak 300 FNL 1260 FEL 723S/17E 0.6 m shell bed 052704.069Garza Peak 200 FNL 2430 FEL 723S/17E 0.4 m shell bed 052704.07a9Garza Peak 120 FNL 2400 FEL 723S/17E sample from bottom of 1.6 m shell bed 052704.07b9Garza Peak 120 FNL 2400 FEL 723S/17E sample from middle of 1.6 m shell bed 052704.07c9Garza Peak 120 FNL 2400 FEL 723S/17E sample from top of 1.6 m shell bed 052704.089Garza Peak 30 FNL 2350 FEL 723S/17E 0.4 m shell bed1In feet, as scaled from field maps. FEL from Eas t line; FWL from West line; FNL from North line ; FSL from South line.2Mt. Diablo Base and Meridian except locality 053102 .01 in San Bernardino Base and Meridian. Notes: a. Sample was not processed b. locality photographed but not sampled c. Sample was thin-sectioned d. 40Ar/39Ar date by the University of Nevada, Las Vegas, Geo chronology Laboratory

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1 2 3 4 5 6 7 8 9 NorthIndexMap 10

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10 11 12 SouthIndexMap

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110702.01-03 110702.04 100299.01 110702.05 121401.01a-b 121401.02 121401.03 100299.02 110702.08 110702.07 110702.06 Map1

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110702.09 110702.10 101301.02a-b 051599.02 111700.01 051599.01 Map2

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030202.07-08 030202.09 030202.06 101301.05a-b 030202.04 030202.03 030202.05 101301.06 052902.03 052902.04 111800.03 101301.04 121500.01a-b,x 021701.02 111800.01a-c 121500.02a-c 121500.03 052802.01 111800.02 100700.03 100700.02 100700.01 100700.00 021701.01 101301.01a-c 101301.03 101301.02a-b 051599.02 111700.01 051599.01 100700.04-04a Map3

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052802.02 052802.03-03a 101301.07 052802.05 052802.06a-b 052802.04 101301.08a-d 052802.08 030202.02 030202.01a-c 052902.01 052902.02 052802.07 030202.04 030202.03 030202.05 101301.06 Map4

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052802.09 052802.10 030202.10 030202.11 Map5

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061001.01 Map6

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053002.02 053002.01a-c Map7

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053002.04 053002.03 Map8

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110802.04 052704.03 110802.05 110802.01 110802.02 110802.03 052704.04 052704.06 052704.07a-c 052704.08 052704.05 052704.01 052704.02 Map9

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052303.03 052304.04 052303.02 052303.01-01a Map10

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060701.01 Map11

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053102.01 Map12

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Appendix B

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Appendix BCatalog of the Late Neogene Molluscs from the Coali nga Region, Fresno and Kings Counties, California (Santa Margarita Formation and Etchegoin Group): Part 1: Plate References J. Richard Bowersox June 2001B-1

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Appendix B (Continued)PLATE REFERENCES OF BIVALVE SPECIES 1. Acila (Truncacila) castrensis (Hinds) Grant and Gale (1931), Pl. 1, Fig. 6a-b Woodring, et al, (1940), Pl. 11, Fig. 11-17 Hertlein and Grant (1972), Pl. 27, Fig. 7-10 Moore (1983), Pl. 1, Fig. 24 2. Aldula gruneri (Philippi) McLean (1969), Fig. 37 3. Aloidis (Corbula) gibbiformis (Grant and Gale) Grant and Gale (1931), Pl. 19, Fig. 4-6 Woodring (1938), Pl. 6, Fig. 8-9 Hertlein and Grant (1972), Pl. 57, Fig. 3-4 4. Amiantis callosa (Conrad) Grant and Gale (1931), Pl. 17, Fig. 7-9, 11-14 Moore (1968), Pl. 29b-c 5. Amiantis communis Nomland Nomland (1917b), Pl. 14, Fig. 2a-d Clark (1929), Pl. 30, Fig. 3-4 6. Anadara (Anadara) trilineata (Conrad) Arnold (1909), Pl. 18, Fig. 1a-b Grant and Gale (1931), Pl. 2, Fig. 1, 4 Woodring, et al, (1940), Pl. 11, Fig. 10, 19-24; P l. 14, Fig. 7; Pl. 20, Fig. 15-17; Pl. 24, Fig. 7; Pl. 29, Fig. 2; Pl. 31 Fig. 9 Woodring and Bramlette (1950), Pl. 9, Fig. 2, 4; Pl 11, Fig. 4 Moore (1968), Pl. 16a-b Hertlein and Grant (1972), Pl. 28, Fig. 1-4, 6 Moore (1983), Pl. 7, Fig. 7-9 7. Anadara trilineata canalis (Conrad) Clark (1929), Pl. 36, Fig. 3 Moore (1983), Pl. 8, Fig. 4 8. Anodonta kettlemanensis Arnold Arnold (1909), Pl. 30, Fig. 10 Woodring, et al, (1940), Pl. 6, Fig. 1-3 9. Anodonta nitida Nomland Nomland (1917a), Pl. 9, Fig. 2 10. Arca (Arca) sisquocensis Reinhart Hertlein and Grant (1972), Pl. 27, Fig. 26, 27, 3133 Moore (1983), Pl. 5, Fig. 6,8 11. Argopecten circularis eldridgei (Arnold) Woodring, et al, (1940), Pl. 24, Fig. 10-13 Moore (1984), Pl. 9, Fig. 11 B-2

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Appendix B (Continued)12. Argopecten circularis impostor (G.D. Hanna) Woodring, et al, (1940), Pl. 13, Fig. 3, 4, 6-9 Adegoke (1969), Pl. 2, Fig. 12 Moore (1984), Pl. 10, Fig. 1 13. Argopecten deserti (Conrad) Arnold (1909), Pl. 26, Fig. 3-4 Nomland (1917a), Pl. 6, Fig. 1, 1a, 1b Grant and Gale (1931), Pl. 5, Fig. 3, 5, 6 Moore (1984), Pl. 9, Fig. 2 14. Atrina alamedensis (Yates) Moore (1983), Pl. 23, Fig. 3; Pl. 27, Fig. 1,3 15. Atrina bicuneata (Nomland) Nomland (1917b), Pl. 15, Fig. 1a-b Moore (1983), Pl. 23, Fig. 4 16. Chaceia ovoidea (Gould) Woodring, et al, (1940), Pl. 14, Fig. 6 Kennedy (1974), Fig. 20-27 17. Chama (Chama) arcana Bernard Arnold (1909), Pl. 26, Fig. 5 Woodring, et al, (1940), Pl. 14, Fig. 1-4, 10 Hertlein and Grant (1972), Pl. 43, Fig. 12, 15 Moore (1988), Pl. 10, Fig. 6, 8-10; Pl. 11, Fig. 10 14, 17-19 18. Chione (Anomalocardia) fernandoensis English Clark (1929), Pl. 42, Fig. 5-6 19. Chione (Chionopsis) coalingensis Adegoke Adegoke (1969), Pl. 6, Fig. 6, 7, 10, 12 20. Chione (Chionopsis) semiplicata Nomland Nomland (1917b), Pl. 15, Fig. 2a-c Clark (1929), Pl. 30, Fig. 1-2 21. Chione (Securella) elsmerensis (English) Nomland (1916), Pl. 9, Fig. 3a-b; Pl. 10, Fig. 1 Clark (1929), Pl. 43, Fig. 1 Grant and Gale (1931), Pl. 16, Fig. 6a-b, 7 22. Chione (Securella) marginata (Anderson and Martin) Anderson and Martin (1914), Pl. 2, Fig. 1 Adegoke (1969), Pl. 6, Fig. 2, 13 23. Chione securis (Shumard) Arnold (1909), Pl. 15, Fig. 2 Clark (1929), Pl. 43, Fig. 2, 4 Grant and Gale (1931), Pl. 17, Fig. 1-6 B-3

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Appendix B (Continued)24. Chlamys egregarius (Nomland) Moore (1984), Pl. 6, Fig. 5 25. Chlamys hastata hastata (Sowerby) Grant and Gale (1931), Pl. 11, Fig. 6a-b Hertlein and Grant (1972), Pl. 33, Fig. 4-6 Moore (1984), Pl. 5, Fig. 4, 6 26. Chlamys hodgei (Hertlein) Moore (1984), Pl. 4, Fig. 5, 9; Pl. 5, Fig. 2 27. Clementia (Egesta) martini (Clark) Clark (1915), Pl. 54, Fig. 1 Woodring (1926), Pl. 15, Fig. 3 28. Clementia (Egesta) pertenius (Gabb) Woodring (1926), Pl. 16, Fig. 1-6 29. Clinocardium (Clinocardium) meekianum (Gabb) Arnold (1909), Pl. 17, Fig. 7 Clark (1929), Pl. 43, Fig. 3 Woodring, et al, (1940), Pl. 24, Fig. 8-9; Pl. 29, Fig. 3, 14 Moore (1999), Pl. 3, Fig. 9 30. Clinocardium (Clinocardium) nuttallii (Conrad) Grant and Gale (1931), Pl. 19, Fig. 14, 17 Hertlein and Grant (1972), Pl. 46, Fig. 21 Moore (1999), Pl. 4, Fig. 6-7 31. Compsomyax subdiaphana (Carpenter) Grant and Gale (1931), Pl. 17, Fig. 10a-b, 15 Hertlein and Grant (1972), Pl. 47, Fig. 4; Pl. 57, Fig. 15 32. Crassadoma gigantea (Gray) Arnold (1909), Pl. 10, Fig. 2 Woodring, et al, (1940), Pl. 31, Fig. 3-4, 8 Moore (1984), Pl. 26, Fig. 1, 5; Pl. 27, Fig. 2-4 33. Crassostrea? eucorrugata (Hertlein) Moore (1987), Pl. 25, Fig. 3-5; Pl. 26, Fig. 1; Pl. 27, Fig. 1 34. Crassostrea titan (Conrad) Arnold (1909), Pl. 10, Fig. 5; Pl. 11, Fig. 2 Clark (1915), Pl. 44, Fig. 1 Nomland (1917b), Pl. 16, Fig. 1; Pl. 17, Fig. 1 Adegoke (1969), Pl. 5, Fig. 1-3, 6, 8; Pl. 6, Fig. 1 Addicott (1972), Pl. 4, Fig. 11 Moore (1987), Pl. 23, Fig. 1-7; Pl. 24, Fig. 1, 3, 4, 6: Pl. 27, Fig. 4; Pl. 28, Fig. 3, 5; Pl. 29, Fig. 1, 6 B-4

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Appendix B (Continued)35. Cryptomya californica (Conrad) Arnold (1909) Pl. 22, Fig. 5 Clark (1915), Pl. 60, Fig. 3-4 Grant and Gale (1931), Pl. 21, Fig. 7, 8, 11, 14 Woodring and Bramlette (1950), Pl. 7, Fig. 2 Hertlein and Grant (1972), Pl. 55, Fig. 3, 4, 7, 10 16 36. Cryptomya quadrata Arnold Arnold (1909), Pl. 21, Fig. 2, 2a Nomland (1917a), Pl. 8, Fig. 1, 1a Clark (1929), Pl. 42, Fig. 4 Woodring, et al, (1940), Pl. 39, Fig. 2 37. Cumingia californica Conrad Arnold and Anderson (1907), Pl. 23, Fig. 5 38. Cyrena (Corbicula) californica Clark Clark (1915), Pl. 56, Fig. 2 39. Dendostrea? vespertina (Conrad) Arnold (1909), Pl. 24, Fig. 4-5; Pl. 29, Fig. 5-6 Clark (1929), Pl. 46, Fig. 3 Grant and Gale (1931), Pl. 12, Fig. 1a-b Woodring (1938), Pl. 8, Fig. 1-4, 8-9; Pl. 9, Fig. 5 Woodring, et al, (1940), Pl. 8, Fig. 10-14, Pl. 10, Fig. 1-5; Pl. 14, Fig. 9 Hertlein and Grant (1972), Pl. 39, Fig. 1-9 Moore (1987), Pl.11, Fig. 2, 5; Pl. 12, Fig. 2, 5-6 ; Pl. 13, Fig. 5; Pl. 14, Fig. 2; Pl. 15, Fig. 2, 3, 6, 7; Pl. 16, Fig. 6-7 40. Dosinia (Dosinella) arnoldi Clark Clark (1915), Pl. 51, Fig. 1-2; Pl. 64, Fig. 5 41. Dosinia (Dosinella) jacalitosana Arnold Arnold (1909), Pl. 16, Fig. 5 Nomland (1917a), Pl. 10, Fig. 1, 1a Clark (1929), Pl. 36, Fig. 4 42. Dosinia (Dosinella) merriami occidentalis Clark Clark (1915), Pl. 50, Fig. 1 Clark (1929), Pl. 36, Fig. 1 43. Dosinia (Dosinella) ponderosa Gray Grant and Gale (1931), Pl. 15, Fig. 1-4 *Woodring, et al, (1946), Pl. 36, Fig. 15-16 Woodring and Bramlette (1950), Pl. 19, Fig. 1;Pl. 2 0, Fig. 7 Moore (1968), Pl. 17a-b B-5

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Appendix B (Continued)44. Felaniella (Felaniella) cornea Reeve Arnold (1909), Pl. 17, Fig. 5 Grant and Gale (1931), Pl. 14, Fig. 12a-b Woodring, et al, (1940), Pl. 35, Fig. 6 Moore (1988), Pl. 9, Fig. 1-3; Pl. 10, Fig. 11 45. Felaniella (Felaniella) harfordi (Anderson) Arnold (1909), Pl. 17, Fig. 6 Moore (1988), Pl. 8, Fig. 21, 25-29 46. Gari (Gobraeus) fucata (Hinds) Grant and Gale (1931), Pl. 21, Fig. 5 Adegoke (1969), Pl. 8, Fig. 8 47. Glycymeris (Axinola) grewingki Dall Arnold (1909), Pl. 19, Fig. 3; Pl. 20, Fig. 3, 3a Clark (1915), Pl. 48, Fig. 4, 9-10 Clark (1929), Pl.42, Fig. 3 Woodring, et al, (1940), Pl. 29, Fig. 10-11; Pl. 33 Fig. 7-8 Hertlein and Grant (1972), Pl. 27, Fig. 14, 19, 24 Moore (1983), Pl. 12, Fig. 20 48. Hinnites benedicti Adegoke Adegoke (1969), Pl. 3, Fig. 3, 5 Moore (1984), Pl. 26, Fig. 2 49. Leporimetis obesa (Deshayes) Clark (1915), Pl. 64, Fig. 2 Hertlein and Grant (1972), Pl. 53, Fig. 14, 17, 19 Moore (1968), Pl. 30a-b 50. Leporimetis cf. L. dombei (Hanley) Woodring, et al, (1940), Pl. 32, Fig. 2 51. Lucina (Lucinisca) nuttalli nuttalli (Conrad) Grant and Gale (1931), Pl. 14, Fig. 4, 18 Moore (1968), Pl. 18d Hertlein and Grant (1972), Pl. 45, Fig. 1-4 Moore (1988), Pl. 1, Fig. 3-6, 9, 12 52. Lucinoma annulatam (Reeve) Grant and Gale (1931), Pl. 14, Fig. 22 Woodring and Bramlette (1950), Pl. 19, Fig. 8 Moore (1968), Pl. 18a-c Hertlein and Grant (1972), Pl. 46, Fig. 12, 19 Moore (1988), Pl. 4, Fig. 4, 5, 16, 23, 27 B-6

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Appendix B (Continued)53. Lyropecten crassicardo (Conrad) Arnold (1909), Pl. 12, Fig. 1 Clark (1915), Pl. 45, Fig. 3;Pl. 46, Fig. 3 Nomland (1917b), Pl. 18, Fig. 1, 1a-b; Pl. 19, Fig. 4 Clark (1929), Pl. 32, Fig. 1 Adegoke (1969), Pl. 2, Fig. 8 Addicott (1972), Pl. 3, Fig. 4, Pl. 4, Fig. 2 Moore (1984), Pl. 17, Fig. 6-7; Pl. 18, Fig. 1-3, 5 ; Pl. 21, Fig. 3; Pl. 28, Fig. 1 54. Lyropecten estrellanus (Conrad) Arnold (1909), Pl. 10, Fig. 3 Clark (1915), Pl. 47, Fig. 4 Clark (1929), Pl. 32, Fig. 4 Grant and Gale (1931), Pl. 8, Fig. 1-2, 4; Pl. 9, F ig. 2 Adegoke (1969), Pl. 2, Fig. 13 Moore (1984), Pl. 9, Fig. 2; Pl. 19, Fig. 2 55. Lyropecten terminus (Arnold) Clark (1929), Pl. 37, Fig. 4 Moore (1984), Pl. 19, Fig. 1, 5 56. Macoma affinis Nomland Woodring, et al, (1940), Pl. 15, Fig. 13; Pl. 34, F ig. 1-4 57. Macoma affinis Normland plena Stewart Woodring, et al, (1940), Pl. 24, Fig. 3; Pl. 29, Fi g. 12; Pl. 39, Fig. 3 Adegoke (1969), Pl. 6, Fig. 4 587. Macoma diabloensis Clark Clark (1915), Pl. 61, Fig. 8-9 59. Macoma (Rexithaerus) indentata Carpenter Hertlein and Grant (1972), Pl. 52, Fig. 3, 4, 7 60. Macoma (Heteromacoma) inquinata (Deshayes) Arnold (1909), Pl. 29, Fig. 3 Nomland (1917a), Pl. 9, Fig. 1, 1a-b Grant and Gale (1931), Pl. 20, Fig. 5 Hertlein and Grant (1972), Pl. 52, Fig. 1, 10 61. Macoma jacalitosana Arnold Arnold (1909), Pl. 16, Fig. 2 62. Macoma (Heteromacoma) nasuta (Conrad) Arnold (1909), Pl. 20, Fig. 6; Pl. 25, Fig. 5 Clark (1915), Pl. 61, Fig. 16 Grant and Gale (1931), Pl. 20, Fig. 11a-b Woodring, et al, (1940), Pl. 14, Fig. 5; Pl. 20, Fi g. 12 Hertlein and Grant (1972), Pl. 54, Fig. 6 B-7

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Appendix B (Continued)63. Macoma (Rexithaerus) secta (Conrad) Arnold (1909), Pl. 20, Fig. 1 Grant and Gale (1931), Pl. 20, Fig. 6a-b Woodring, et al, (1940), Pl. 16, Fig. 1 64. Macoma vanvlecki Arnold Arnold (1909), Pl. 12, Fig. 2; Pl. 16, Fig. 1 Nomland (1917a), Pl. 8, Fig. 3, 3a 65. Mactromeris albaria albaria (Conrad) Arnold (1909), Pl. 19, Fig. 4 Clark (1915), Pl. 60, Fig. 8 Grant and Gale (1931), Pl. 23, Fig. 3a-b Moore (1999), Pl. 9, Fig. 1, 2, 5, 7, 9 66. Mactromeris catilliformis catilliformis (Conrad) Clark (1915), Pl. 59, Fig. 1 Grant and Gale (1931), Pl. 23, Fig. 4, 10 Hertlein and Grant (1972), Pl. 54, Fig. 5 Moore (1999), Pl. 8, Fig. 1-3, 9 67. Mactromeris hemphillli (Dall) Hertlein and Grant (1972), Pl. 54, Fig. 1-4, 9 68. ?Mactromeris coalingensis (Arnold) Arnold (1909), Pl. 25, Fig. 4 Woodring, et al, (1940), Pl. 33, Fig. 1 69. Modiolus (Modiolus) capax (Conrad) Woodring, et al, (1940), Pl. 16, Fig. 3 Moore (1983), Pl. 20, Fig. 6 70. Modiolus (Modiolus) modiolus (Linne) Woodring, et al, (1940), Pl. 37, Fig. 1-2 71. Modiolus (Modiolusia) rectus (Conrad) Arnold (1909), Pl. 20, Fig. 4 Woodring, et al, (1940), Pl. 13, Fig.15 ;Pl. 20, Fi g. 13-14 Hertlein and Grant (1972), Pl. 42, Fig. 7 Moore (1983), Pl. 20, Fig. 9 72. Mya (Arenomya) arenaria Linnaeus Arnold (1909), Pl. 29, Fig. 7-8 as Mya japonica Jay Clark (1915), Pl. 63, Fig. 3, 4 as Mya dickersoni n. sp. Grant and Gale (1931), Pl. 21, Fig. 13 Woodring, et al, (1940), Pl. 24, Fig. 2, 21 as Mya dickersoni Clark MacNeil (1965), Pl. 5, Fig. 2-12; Pl. 6, Fig. 1-14, 17, 18 Adegoke (1969), Pl. 9, Fig. 3, 7; Fig. 6, 9 as Mya japonica Jay B-8

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Appendix B (Continued)73. Mya (Arenomya) macneili Adegoke Adegoke (1969), Pl. 9, Fig. 1, 4, 5, 10 74. Mytilus (Crenomytilus) coalingensis Arnold Arnold (1909), Pl. 19, Fig. 5; Pl. 22, Fig. 6 Woodring, et al, (1940), Pl. 32, Fig. 3, 4 Moore (1983), Pl. 15, Fig. 1-3 75. Mytilus (Crenomytilus) kewi Nomland Nomland (1917b), Pl. 14, Fig. 1 Moore (1983), Pl. 15, Fig. 4 76. Mytilus (Mytilus) edulis Linne Woodring, et al, (1940), Pl. 8, Fig. 8 Moore (1983), Pl. 13, Fig. 11, 12 77. Nanaochlamys nurtteri (Arnold) Arnold (1909), Pl. 27, Fig. 3, 4 Moore (1984), Pl. 8, Fig. 4, 5 78. Nuculana (Saccella) taphria (Dall) Grant and Gale (1931), Pl. 1, Fig. 8, 9 Woodring and Bramlette (1950), Pl. 21, Fig. 7 Moore (1968), Pl. 23e-g Adegoke (1969), Pl. 1, Fig. 9 Hertlein and Grant (1972), Pl. 27, Fig. 11-13, 16-1 8 Moore (1983), Pl. 2, Fig. 22-23 79. Nuttallia nuttalli (Conrad) Clark (1915), Pl. 61, Fig. 15 80. Oppenheimopecten coalingaensis (Arnold) Arnold (1909), Pl. 26, Fig. 1-2 Clark (1929), Pl. 38, Fig. 2-3 Woodring, et al, (1940), Pl. 13, Fig. 17-18; Pl. 16 Fig. 4 Adegoke (1969), Pl. 1, Fig. 1, 14 Moore (1984), Pl. 33, Fig. 3 81. Ostrea conchaphila (Carpenter) Moore (1987), Pl. 30, Fig. 1-4, 6, 8 82. Ostrea (Ostrea) atwoodi Gabb Arnold (1909), Pl. 17, Fig. 1-2 Woodring, et al, (1940), Pl. 29, Fig. 1, 13 Moore (1987), Pl. 30, Fig. 7, 9 83. Pacifipecten discus Conrad Grant and Gale (1931), Pl. 4, Fig. 7 Moore (1984), Pl. 14, Fig. 3-5, 7-9 B-9

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Appendix B (Continued)84. Pandora (Heteroclidus) punctata Conrad Arnold (1909), Pl. 27, Fig. 10 Grant and Gale (1931), Pl. 13, Fig. 2 Woodring, et al, (1940), Pl. 29, Fig. 4 Woodring and Bramlette (1950), Pl. 17, Fig. 13 Hertlein and Grant (1972), Pl. 42, Fig. 2-3, 9-10 Moore (1968), Pl. 31a-b 85. Panope gererosa (Gould) Arnold (1909), Pl. 15, Fig. 1 as Panope estrellana Conrad; Pl. 18, Fig. 4 Clark (1915), Pl. 62, Fig. 1 Grant and Gale (1931), Pl. 21, Fig. 12 Woodring, et al, (1940), Pl. 14, Fig. 11 Hertlein and Grant (1972), Pl. 56, Fig. 19-20 Moore (1968), Pl. 19 86. Patinopecten healeyi (Arnold) Grant and Gale (1931), Pl. 6, Fig. 1-2 Woodring and Bramlette (1950), Pl. 19, Fig. 9; Pl. 21, Fig. 9 Hertlein and Grant (1972), Pl. 31, Fig. 1, 4, 6, 7; Pl. 33, Fig. 9;Pl. 36, Fig. 8-9 Moore (1968), Pl. 21a-b Moore (1984), Pl. 34, Fig. 3; Pl. 35, Fig. 3; Pl. 3 6, Fig. 4; Pl. 37, Fig. 3; Pl. 38, Fig. 2-5;Pl. 39, Fig. 1; Pl. 40, Fig. 5; Pl. 41, Fi g. 2; Pl. 42, Fig. 1-3 87. Patinopecten lohri (Hertlein) Arnold (1909), Pl. 23, Fig. 1 Woodring, et al, (1940), Pl. 35, Fig. 2-5 Woodring and Bramlette (1950), Pl. 7, Fig. 7, 9 Adegoke (1969), Pl. 2, Fig. 6, 9 Moore (1984), Pl. 34, Fig. 2; Pl. 36, Fig. 2-3 88. Pecten (Pecten) bellus (Conrad) Clark (1929), Pl. 40, Fig. 1-2 Grant and Gale (1931), Pl. 3, Fig. 1a-b Hertlein and Grant (1972), Pl. 30, Fig. 1-4, 9; Pl. 32, Fig. 14 Moore (1984), Pl. 29, Fig. 1-4 89. Penitella penita (Conrad) Grant and Gale (1931), Pl. 24, Fig. 1a-b Woodring and Bramlette (1950), Pl. 8, Fig. 6; Pl. 1 4, Fig. 3 Addicott (1966), Pl. 4, Fig. 1 Hertlein and Grant (1972), Pl. 56, Fig. 8; Pl. 57, Fig. 1-2 Kennedy (1974), Fig. 46-54 B-10

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Appendix B (Continued)90. Petricola carditoides (Conrad) Grant and Gale (1931), Pl. 13, Fig. 14a-b Addicott (1966), Pl. 4, Fig. 2-3 91. Pisidium supinum Schmidt Woodring, et al, (1940), Pl. 5, Fig. 35-38 92. Placunanomia californica Arnold Arnold (1909), Pl. 24, Fig. 2-3 Adegoke (1969), Pl. 10, Fig. 4 Moore (1987), Pl. 6, Fig. 5, 11 93. Platyodon colobus Woodring Woodring, et al, (1940), Pl. 21, Fig. 1-2 94. Pododesmus (Monia) macroschisma (Deshayes) Arnold (1909), Pl. 14, Fig. 1 Grant and Gale (1931), Pl. 12, Fig. 3-4 Hertlein and Grant (1972), Pl. 40, Fig. 3; Pl. 41, Fig. 9, 12-13 Moore (1987), Pl. 7, Fig. 4; Pl. 8, Fig. 4, 7; Pl. 9, Fig. 7 95. Protothaca (Callithaca) tenerrima (Carpenter) Arnold (1909), Pl. 18, Fig. 3 Grant and Gale (1931), Pl. 18, Fig. 9 Hertlein and Grant (1972), Pl. 51, Fig. 1-3; Pl. 52 Fig. 13, 14 96. Protothaca (Protothaca) staminea (Conrad) Clark (1915), Pl. 56, Fig. 5 Clark (1929), Pl. 32, Fig. 6 Grant and Gale (1931), Pl. 18, Fig. 1-3 97. Protothaca grata (Say) tarda (Stewart) Woodring, et al, (1940), Pl. 13, Fig. 10-13 98. Protothaca jacalitosensis (Arnold) Arnold (1909), Pl. 16, Fig. 4 99. Protothaca staleyi (Gabb) Arnold (1909), Pl. 26, Fig. 8 Woodring and Bramlette (1950), Pl. 21, Fig. 2-4 100. Protothaca staleyi (Gabb) hannibali (Howe) Woodring, et al, (1940), Pl. 29, Fig. 8 Adegoke (1969), Pl. 3, Fig. 10 101. Psephidia lordi (Baird) Grant and Gale (1931), Pl. 15, Fig. 5-7 B-11

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Appendix B (Continued)102. Pseudocardium densatum densatum (Conrad) Arnold (1909), Pl. 17, Fig. 3-4; Pl. 21, Fig. 3 Clark (1915), Pl. 60, Fig. 5 Woodring, et al, (1940), Pl. 24, Fig. 14-15, 19-20 ; Pl. 29, Fig. 16; Pl. 30, Fig. 1-6; Pl. 37, Fig.8; Pl. 39, Fig. 3-10 Woodring and Bramlette (1950), Pl. 17, Fig. 14; Pl. 19, Fig. 2 103. Pseudocardium pabloensis (Packard) Clark (1915), Pl. 60, Fig. Clark (1929), Pl. 33, Fig. 2 104. Saxidomus nuttalli Conrad Arnold (1909), Pl. 21, Fig. 4 Clark (1915), Pl. 57, Fig. 1-2 Grant and Gale (1931), Pl. 18, Fig. 4, 10-11 Woodring, et al, (1940), Pl. 16, Fig. 8; Pl. 33, Fi g. 9 Adegoke (1969), Pl. 7, Fig. 1, 4 Hertlein and Grant (1972), Pl. 50, Fig. 8-10 105. Semele fausta Nomland Nomland (1917a), Pl. 9, Fig. 3, 3a-b 106. Semele flavescens (Gould) Keen (1971), Fig. 630 107. Semele (Semele) rubropicta Dall Arnold (1909), Pl. 25, Fig. 3 Woodring and Bramlette (1950), Pl. 14, Fig. 12 Hertlein and Grant (1972), Pl. 48, Fig. 1, 2, 7, 11 108. Siliqua lucida (Conrad) Clark (1915), Pl. 44, Fig. 3 Grant and Gale (1931), Pl. 21, Fig. 6 Hertlein and Grant (1972), Pl. 49, Fig. 2 Moore (1999), Pl. 14, Fig. 8 109. Siliqua patula (Dixon) Grant and Gale (1931), Pl. 21, Fig. 9 110. Solen (Ensisolen) sicarius Gould Arnold (1909), Pl. 29, Fig. 4 Grant and Gale (1931), Pl. 21, Fig. 4 Hertlein and Grant (1972), Pl. 49, Fig. 7 Moore (1999), Pl. 14, Fig. 1 111. Solen (Eosolen) perrini Clark Clark (1915), Pl. 44, Fig. 2 Clark (1929), Pl. 31, Fig. 7 Woodring, et al, (1940), Pl. 8, Fig. 9; Pl. 24, Fig 1 B-12

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Appendix B (Continued)112. Sphaerium striatianum (Lamarck) Woodring, et al, (1940), Pl. 5, Fig. 29-34 113. Stereomactra abscissa (Gabb) Arnold (1909), Pl. 12, Fig. 3 Clark (1929), Pl. 22, Fig. 3, 5 Moore (1999), Pl. 12, Fig. 1, 6 114. Striostrea? bourgeoissi bourgeoissi (Remond) Clark (1915), Pl. 43, Fig. Moore (1987), Pl. 25, Fig. 1; Pl. 26, Fig. 5 115. Swiftopecten parmeleei etchegoini (Anderson) Nomland (1917a), Pl. 7, Fig. 1-5; Pl. 8, Fig. 2, 2a -b Clark (1929), Pl. 37, Fig. 2-3 Woodring, et al, (1940), Pl. 13, Fig. 5; Pl. 32, Fi g. 1 Moore (1984), Pl. 22, Fig. 2-3 116. Swiftopecten parmeleei parmeleei (Dall) Arnold (1909), Pl. 27, Fig. 1-2 Grant and Gale (1931), Pl. 10, Fig. 1-5, 7 cf. Hertlein and Grant (1972), Pl. 31, Fig. 5; Pl. 37, Fig. 1-10 Moore (1984), Pl. 23, Fig. 1, 3-4 117. Tellina aragonia Dall Arnold (1909), Pl. 14, Fig. 2 Adegoke (1969), Pl. 8, Fig. 2 118. Tellina (Peronida) bodegensis Hinds Grant and Gale (1931), Pl. 20, Fig. 13 Woodring, et al, (1940), Pl. 33, Fig. 2 Hertlein and Grant (1972), Pl. 53, Fig. 9, 18 119. Tellina englishi Clark Clark (1915), Pl. 61, Fig. 6-7 120. Tellina ocoyana Conrad Anderson and Martin (1914), Pl. 2, Fig. 3a-c 121. Tellina woodringi Adegoke Adegoke (1969), Pl. 8, Fig. 1, 4-6 122. Thracia formosa Nomland Nomland (1917a), Pl. 9, Fig. 4, 4a 123. Thracia jacalitosana Arnold Arnold (1909), Pl. 16, Fig. 3 124. Tivela trigonalis Nomland Nomland (1916), Pl. 9, Fig. 2a-c B-13

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Appendix B (Continued)125. Trachycardium (Dallocardia) quadragenarium (Conrad) Clark (1915), Pl. 47, Fig. 3 Grant and Gale (1931), Pl. 19, Fig. 15 Woodring, et al, (1940), Pl. 16, Fig. 2 Woodring, et al, (1946), Pl. 34, Fig. 18-19 Hertlein and Grant (1972), Pl. 46, Fig. 18, 20, 23 126. Trachycardium (Dallocardia) sagaseri Adegoke Adegoke (1969), Pl. 3, Fig. 4, 6, 8 Moore (1999), Pl. 3, Fig. 15 127. Transennella tantilla (Gould) Arnold (1909), Pl. 26, Fig. 7, 7a Grant and Gale (1931), Pl. 15, Fig. 8 Hertlein and Grant (1972), Pl. 44, Fig. 20, 23, 25, 27 128. Tresus nuttallii (Conrad) Clark (1915), Pl. 59, Fig. 2 Grant and Gale (1931), Pl. 22, Fig. 6, 8-9; Pl. 23, Fig. 8-9 Woodring, et al, (1940), Pl. 11, Fig. 25; Pl. 18, F ig. 15; Pl. 33, Fig. 6,9 Hertlein and Grant (1972), Pl. 55, Fig. 13, 15, 17 Moore (1968), Pl. 33-34 129. Tresus pajaroanus (Conrad) Adegoke (1969), Pl. 7, Fig. 5 130. Zirfaea dentata Gabb Clark (1915), Pl. 63, Fig. 1-2 Kennedy (1974), Fig. 13-15 131. Zirfaea pilsbryi Lowe Grant and Gale (1931), Pl. 24, Fig. 2 Woodring, et al, (1940), Pl. 34, Fig. 7 Adegoke (1969), Pl. 9, Fig. 2, 8, 11-12; Pl. 10, Fi g. 3, 5, 6, 13 Kennedy (1974), Fig. 16-18 B-14

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Appendix B (Continued)PLATE REFERENCES OF GASTROPOD SPECIES 1. Acanthina (Monocero) norna Nomland Nomland (1917b), Plate 19 2. Astraea (Pachypoma?) biangulata (Gabb) 3. Astraea (Pomaulax) gibberosa (Dillwyn) 4. Bittium (Lyrobittium) asperum (Gabb) Grant and Gale (1934), Plate 24 Woodring, et al, (1940), Plate 29 Adegoke (1969), Plate 11 5. Boreotrophon stuarti (Smith) Arnold (1909), Plate 25 6. Calicantharus fortis (Carpenter) Grant and Gale (1934), Plate 28 7. Calicantharus fortis (Carpenter) angulatus (Arnold) Woodring, et al, (1946), Plate 29 Woodring and Bramlette (1950), Plates 14-15 8. Calicantharus humerosus (Gabb) Grant and Gale (1934), Plate 28 9. Calliosioma etchegoinensis Nomland Nomland (1916), Plate7 Grant and Gale (1934), Plate 32 10. Calliostoma kerri Arnold Arnold (1909), Plate 27 Woodring, et al, (1940), Plate 15 11. Calliostoma coalingense Arnold Arnold (1909), Plate 27 Clark (1929), Plate 50 Woodring, et al, (1940), Plates 11 and 15 12. Calliostoma coalingense Arnold privum Stewart Woodring, et al, (1940), Plate 32 Adegoke (1969), Plate 10 13. Calliostoma gemmulatum Carpenter Grant and Gale (1934), Plate 32 Woodring, et al, (1940), Plate 15 14. Calyptraea filosa (Gabb) Clark (1915), Plate 65 Clark (1929), Plate 34 (10) Woodring, et al, (1940), Plate 8 B-15

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Appendix B (Continued)15. Calyptraea inornata (Gabb) Grant and Gale (1934), Plate 32 Woodring, et al, (1940), Plates 11, 15, and 20 16. Cancellaria altispira Gabb 17. Cancellaria crassa Nomland Nomland (1917a), Plate 12 18. Cancellaria fernandoensis Arnold tribulus Nomland Nomland (1917a), Plate 12 19.Cancellaria hemphlli Dall Grant and Gale (1934), Plate 27 Woodring and Bramlette (1950), Plate 15 Adegoke (1969), Plate 13 20. Cancellaria pabloensis Clark Clark (1915), Plate 68 Clark (1929), Plate 34 (14-15, 19) 21. Cancellaria rapa Nomland Nomland (1917a), Plate 11 Woodring, et al, (1940), Plate 15 22. Cancellaria tritonidea Gabb Arnold (1909), Plate 26 Clark (1929), Plates 48 and 50 Grant and Gale (1934), Plate 27 Woodring, et al, (1946), Plate 35 23. Clavus (Clathrodrillia) coalingensis (Arnold) Arnold (1909), Plate 22 Grant and Gale (1934), Plate 26 24. Crepidula adunca Sowerby Clark (1915), Plate 70 Moore (1968), Plate 27 25. Crepidula onyx Sowerby Grant and Gale (1934), Plate 32 Woodring, et al, (1940), Plate 31 26. Crepidula princeps Conrad Arnold (1909), Plate 23 Woodring, et al, (1946), Plate 32 Woodring and Bramlette (1950), Plates 8 and 10-11 Moore (1968), Plate 15 27. Diodora subeilliptica (Nomland) B-16

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Appendix B (Continued)28. Diodora unica (Nomland) Nomland (1917a), Plate 11 (3) 29. Forreria belcheri (Hinds) Woodring, et al, (1946), Plate 35 Addicott (1972), Plate 4 30. Forreria belcheri (Hinds) avita (Nomland) Arnold (1909), Plate 14 Clark (1915), Plate 66 Nomland (1917a), Plate 11 31. Forreria carsiaensis (Anderson) Arnold (1909), Plate 10 Clark (1915), Plate 66 Clark (1929), Plate 34 (11) 32. Forreria carisaensis (Anderson) mirandaensis (Grant and Eaton) Adegoke (1969), Plate 11 33. Forreria coalingensis (Arnold) Arnold (1909), Plate 22 34. Forreria magister (Nomland) Clark (1929), Plate 49 Grant and Gale (1934), Plate 27 Woodring, et al, (1940), Plate 36 35. Forreria magister munda Stewart Woodring, et al, (1940), Plate 15 36. Fusinus? coalingensis (Nomland) 37. Juga kettlemanensis (Arnold) Arnold (1909), Plate 30 Pilsbry (1934), Plate 18 Woodring, et al, (1940), Plate 15 Adegoke (1969), Plate 10 38. Lithoglyphus kettlemanensis (Pilsbry) 39. Littorina mariana Arnold Arnold (1909), Plate 29 Woodring, et al, (1940), Plate 29 40. Littorina mariana Arnold var. alta Arnold Arnold (1909), Plate 29 41. Margarites johnsoni (Arnold) Arnold (1909), Plate 15 42. Margarites cf. M. pupilis B-17

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Appendix B (Continued)43. Megasurcula carpenteriana (Gabb) Grant and Gale (1934), Plate 25 Woodring and Bramlette (1950), Plate 17 Moore (1968), Plate 15 44. Megasurcula carpenteriana (Gabb) fernandoana (Arnold) Grant and Gale (1934), Plate 25 45. Megasurcula tryoniana (Gabb) Woodring and Bramlette (1950), Plate 11 Adegoke (1969), Plate 13 46. Menetus vanvlecki (Arnold) 47. Mitrelia carinata (Hinds) 48. Mitrella gausapata (Gould) Grant and Gale (1934), Plate 26 Woodring, et al, (1940), Plates 11 and 20 Woodring, et al, (1946), Plate 32 Woodring and Bramlette (1950), Plate 15 Adegoke (1969), Plate 11 49. Mitrella richthofeni (Gabb) Arnold (1909), Plate 25 Adegoke (1969), Plate 13 50. Murex rodeoensis (Clark) Adegoke (1969), Plate 11 51. Nassarius (Caesia) coalingensis (Arnold) Woodring, et al, (1940), Plates 11 and 20 Addicott (1965), Plate 2 52. Nassarius (Caesia) grammatus (Dall) Addicott (1965), Plate 2 Moore (1968), Plate 15 53. Nassarius (Caesia) grammatus (Dall) addicotti Adegoke Adegoke (1969), Plate 12 54. Nassarius (Caesia) moranianus (Martin) Woodring, et al, (1940), Plate 34 Woodring and Bramlette (1950), Plates 14, 17, and 1 9 Addicott (1965), Plate 2 55. Nassarius (Caesia) whitneyi (Trask) Addicott (1965), Plate 2 56. Nassarius (Catilon) iniquus (Stewart) Grant and Gale (1934), Plate 26 Woodring, et al, (1940), Plate 34 Addicott (1965), Plate 3 B-18

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Appendix B (Continued)57. Nassarius (Demondia) californianus (Conrad) Arnold (1909), Plate 27 Woodring, et al, (1940), Plate 39 Woodring and Bramlette (1950), Plates 8, 10, 15, an d 19 Addicott (1965), Plate 1 58. Nassarius (Catilon?) antiselli (Anderson and Martin) Anderson and Martin (1914), Plate 7 Addicott (1965), Plate 3 59. Natica (Cryptonatica) clausa Broderip and Sowerby Marincovich (1977), Plates 41-42 60. Neptunea pabloensis (Clark) Clark (1915), Plate 67 (8) 61. Neverita (Glossaulax) andersoni (Clark) Clark (1915), Plate 68 Marincovich (1977), Plate 30 62. Neverita (Glossaulax) reclusiana (Deshayes) Arnold (1909), Plate 27 Woodring, et al, (1940), Plate 39 Woodring and Bramlette (1950), Plates 8, 10, 15, an d 19 Addicott (1965), Plate 1 63. Neverita (Neverita) kirkensis (Clark) Clark (1915), Plates 68-69 Marincovich (1977), Plate 28 64. Nucella etchegoinensis (Arnold) Arnold (1909), Plate 18 Woodring, et al, (1940), Plates 24 and 36 65. Nucella funkeana (Adegoke) Adegoke (1969), Plate 12 66. Nucella lamellosa (Gmelin) Arnold (1909), Plate 9 Grant and Gale (1934), Plate 32 67. Ocenebra dalli (Clark) Clark (1915), Plate 67 68. Ocenebra lurida (Middendorf) Grant and Gale (1934), Plate 32 69. Ocenebra temelenta (Hanna) Nomland (1917a), Plate 12 70. Ocenebra tethys (Nomland) Nomland (1917a), Plate 12 B-19

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Appendix B (Continued)71. Ocenebra? turris (Nomland) Nomland (1917a), Plate 11 72. Odostomia (Evalea) io Dail and Barlsch 73. Olivella baetica Carpenter Clark (1915), Plate 69 Grant and Gale (1934), Plate 24 Woodring, et al, (1940), Plate 20 Woodring, et al, (1946), Plate 35 Woodring and Bramlette (1950), Plate 15 74. Olivella biplicata (Sowerby) Grant and Gale (1934), Plate 24 Woodring and Bramlette (1950), Plate 19 Moore (1968), Plate 28 75. Opalia varicostata Stearns Nomland (1917a), Plate 11 Woodring, et al, (1940), Plate 36 Woodring and Bramlette (1950), Plate 10 Moore (1968), Plate 15 76. Pleropurpura festiva (Hinds) Grant and Gale (1934), Plate 32 Woodring, et al, (1940), Plate 15 77. Polinices (Euspira) diabloensis (Clark) 78. Polinices (Euspira) galianoi Dall Marincovich (1977), Plate 23 79. Polinices (Euspira) lewisii (Gould) Nomland (1916), Plate 7 Arnold (1909), Plate 22 Woodring, et al, (1940), Plates 15 and 31 Woodring and Bramlette (1950), Plate 12 Marincovich (1977), Plate 24 80. Polinices (Euspira) palidus (Broderip and Sowerby) Marincovich (1977), Plate 25 81. Progabbia sp. of Woodring, et al, (1940) Woodring, et al, (1940), Plate 15 (4) 82. Savaginius kettlemanensis (Pilsbry) Pilsbry (1934), Plate 19 83. Savaginius spiralis (Pilsbry) 84. Scalez coalingensis Hanna and Gaylord B-20

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Appendix B (Continued)85. Searlesia portolaensis (Arnold) Arnold (1909), Plate 26 Adegoke (1969), Plate 10 86. Sinum scopulosum (Conrad) Arnold (1909), Plate 24 Woodring and Bramlette (1950), Plate 12 Moore (1968), Plate 15 Marincovich (1977), Plate 33 87. Siphonalia danvillensis Clark Nomland (1917b), Plate 20 88. Siphonalia kettlemanensis (Arnold) Arnold (1909), Plates 15 and 21 Woodring, et al, (1940), Plate 15 and 21 Adegoke (1969), Plate 12 89. Tegula (Chlorostoma) dubiosa Grant and Gale 90. Tegula (Chlorostoma) pulcella Nomland Nomland (1917a), Plate 12 91. Tegula (Chlorostoma) thea Nomland Nomland (1917b), Plate 20 92. Tegula (Chlorostoma) varistriata Nomland Nomland (1917b), Plate 20 93. Thais imperialis (Dall) Arnold (1909), Plate 14 Clark (1915), Plate 68 Clark (1929), Plate 34 (16) 94. Trophon dickersoni Clark Clark (1915), Plate 68 Adegoke (1969), Plate 10 95. Trophon dickersoni Clark nomlandi Adegoke Adegoke (1969), Plate 10 96. Trophon perelegans Nomland Nomland (1917b), Plate 20 97. Trophosycon clallamensis (Weaver) nodibulbosa (Grant and Gale) Grant and Gale (1934), Plate 30 98. Trophosycon ocoyana (Conrad) contignata (Grant and Gale) Grant and Gale (1934), Plates 29-30 99. Trophosycon ocoyana (Conrad) ruginodosa (Grant and Gale) Grant and Gale (1934), Plates 29-30 B-21

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Appendix B (Continued)100. Turittella cooperi Carpenter Grant and Gale (1934), Plate 24 Woodring, et al, (1946), Plate 34 Woodring and Bramlette (1950), Plate 13 Addicott (1972), Plate 4 101. Turritella freya Nomland Nomland (1917b), Plate 19 102. Turritella nova Nomland Clark (1929), Plate 49 (6) 103. Turritella vanvlecki Arnold Arnold (1909), Plate 22 Nomland (1917a), Plate 12 Clark (1929), Plate 49 Grant and Gale (1934), Plate 24 Woodring, et al, (1940 ), Plate 31 104. Valvata humeralis californica Pilsbry B-22

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Appendix B (Continued)REFERENCES Addicott, W.O., 1965, Some western American Cenozoi c gastropods of the genus Nassarius : USGS Professional Paper 503-B, 21 p., 3 pl. Addicott, W.O., 1966, Late Pleistocene marine paleo geography and zoogeography in central California: United States Geological Survey Professional Paper 523-C, 21 p., 4 pl. Addicott, W.O., 1972, Provincial middle and late Te rtiary molluscan stages, Temblor Range, California, in Stinemeyer, E.H., and Church, C.C., Proceedings of the Pacific Coast Miocene Biostratigraphic Symposium: P acific Section Society of Economic Paleontologists and Mineralogists, p. 1-26 4 pl. Adegoke, O.S., 1969, Stratigraphy and paleontology of the marine Neogene formations of the Coalinga region, California: University of Cali fornia, Publications in Geological Sciences, v. 80, 241 p., 13 pl. Arnold, R., 1909, Paleontology of the Coalinga dist rict, Fresno and Kings Counties, California: USGS Bulletin 396, 173 p., 30 pl. Arnold, R., and Anderson, R., 1907, Geology and oil resources of the Santa Maria oil district, Santa Barbara County, california: United States Geological Survey Bulletin 322, 161 p., 26 pl. Anderson, F.M., and Martin, B., 1914, Neocene recor d in the Temblor basin, California, and Neocene deposits of the San Juan district, San Luis Obispo County: Proceedings of the California Academy of Sciences, 4th series, v. 4, p. 15-112, 10 pl. Clark, B.L., 1915, Fauna of the San Pablo Group of middle California: University of California Publications in Geology, v. 8, p. 385-5 72, pl. 42-71. Clark, B.L., 1929, Stratigraphy and faunal horizons of the Coast Ranges of California: Berkeley, California, privately published, 30 p., 5 0 pl. Cote, R.M., 1991, Paleontology of the Santa Margar ita Formation on the Coalinga anticline, Fresno County, California [MS thesis]: N orthridge, California, California State University, Northridge, 259 p., 8 pl. Grant IV, U.S., and Gale, H.R., 1931, Pliocene and Pleistocene Mollusca of California and adjacent regions: San Diego Society of Natural History, Memoir 1, 1036 p., 32 pl. Hertlein, L.G., and Grant IV, U.S., 1972, The geolo gy and paleontology of the marine Pliocene of San Diego, California (Paleontology: Pe lecypoda): San Diego Society of Natural History, Memoir 2, Part 2B, 409 p., 57 p l. Keen, A.M., 1971, Sea Shells of Tropical West Ameri ca, 2nd Edition: Stanford University Press, 1064 p. Kennedy, G.L., 1974, West American Cenozoic Pholadi dae (Mollusca: Bivalvia): San Diego Society of Natural History, Memoir 8, 127 p., 103 fig. Martin, B., 1916, The Pliocene of middle and northe rn California: University of California Publications in Geology, v. 9, p. 215-2 59. B-23

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Appendix B (Continued)MacNeil, F.S., 1965, Evolution and distribution of the genus Mya and Tertiary migrations of Mollusca: USGS Professional Paper 483 -G, 51 p., 11 pl. Marincovich, L., 1977, Cenozoic Naticidae (Mollusca : Gastropoda) of the northeastern Pacific: Bulletins of American Paleontology, v. 70, p. 169-494, pl. McLean, J.H., 1969, Marine Shells of Southern Calif ornia: Los Angeles County Museum of Natural History, Science Series 24, Zoology No. 11, 104 p., 54 fig. Moore, E.J., 1968, Fossil mollusks of San Diego Cou nty: San Diego Society of Natural History, Occasional Paper 15, 76 p., 34 pl. Moore, E.J., 1983, Tertiary marine pelecypods of Ca lifornia and Baja California: Nuculidae through Malleidae: United States Geologic al Survey Professional Paper 1228-A, 108 p., 27 pl. Moore, E.J., 1984, Tertiary marine pelecypods of Ca lifornia and Baja California: Propeamussiidae and Pectinidae: United States Geolo gical Survey Professional Paper 1228-B, 112 p., 42 pl. Moore, E.J., 1987, Tertiary marine pelecypods of Ca lifornia and Baja California: Plicatulidae to Ostreidae: United States Geological Survey Professional Paper 1228C, 53 p., 34 pl. Moore, E.J., 1988, Tertiary marine pelecypods of Ca lifornia and Baja California: Lucinidae through Chamidae: United States Geologica l Survey Professional Paper 1228-D, 46 p., 11 pl. Moore, E.J., 1992, Tertiary marine pelecypods of Ca lifornia and Baja California: Erycinidae through Carditidae: United States Geolog ical Survey Professional Paper 1228-E, 37 p., 9 pl. Moore, E.J., 1999, Tertiary marine pelecypods of Ca lifornia and Baja California, Chapter F: http://www.cmug.com/~chintimp/Tertiary.Pelec ypods.htm, 107 p., 14 pl. Nomland, J.O., 1916, Fauna from the lower Pliocene at Jacalitos Creek and Waltham Canyon, Fresno County, California: University of Ca lifornia Publications in Geology, v. 9, p. 199-214, pl. 9-11. Nomland, J.O., 1917a, The Etchegoin Pliocene of mid dle California: University of California Publications in Geology, v. 10, p. 191-2 54, pl. 6-12. Nomland, J.O., 1917b, Fauna of the Santa Margarita beds in the north Coalinga region of California: University of California Publications i n Geology, v. 10, p. 293-326, pl. 14-20. Pilsbry, H.A., 1934, Mollusks of the fresh-water Pl iocene beds of the Kettleman Hills and neighboring oil fields, California: Proceedings of the Academy of Natural Sciences of Philadelphia, v. 86, p. 541-570, pl. 18-23. Woodring, W.P., 1926, American Tertiary mollusks of the genus Clementia, in Mendenhall, W.C., Shorter Contributions to General Geology, 1926: United States Geological Survey Professional Paper 147, p. 25-48. pl. 14-17. B-24

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Appendix B (Continued)Woodring, W.P., 1938, Lower Pliocene mollusks and e chinoids from the Los Angeles basin, California: United States Geological Survey Professional Paper 190, 65 p., 9 pl. Woodring, W.P., and Bramlette, M.N., 1950, Geology and paleontology of the Santa Maria district, California: United States Geologica l Survey Professional Paper 222, 185 p., 23 pl. Woodring, W.P., and Bramlette, M.N., and Kew, W.S.W ., 1946, Geology and paleontology of Palos Verdes Hills, California: Uni ted States Geological Survey Professional Paper 207, 138 p., 37 pl. Woodring, W.P., Stewart, R., and Richards, R.W., 19 40, Geology of the Kettleman Hills oil field, California: United States Geological Sur vey Professional Paper 195, 170 p., 56 pl.B-25

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Appendix C

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100700.04 100700.03 100700.02 100700.01 100299.01 051599.01 Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Acila castrensis 1 0.00 0.00 0.00 0.00 0.00 0.00 Adula gruneri 2 0.00 0.00 0.00 0.00 0.00 0.00 Aloidis gibbiformis 3 0.00 0.00 0.00 0.00 0.00 0.00 Amiantis callosa 4 0.00 0.00 0.00 0.00 0.00 0.00 Amiantis communis 5 0.00 0.00 0.00 0.00 0.00 2.78 Anadara trilineata 6 0.00 0.00 0.00 0.00 0.00 0.00 Argopecten circularius eldridgii 7 0.00 0.00 0.00 0.00 0.00 0.00 Argopecten circularius impostor 8 0.00 0.00 0.00 0.00 0.00 0.00 Chacaia ovoidea 9 0.00 0.00 0.00 0.00 0.00 0.00 Chama arcana 10 0.00 0.00 0.00 0.00 0.00 0.00 Chione (Chionopsis) semiplicata 11 0.00 0.00 0.00 0.00 0.00 0.00 Chione coalingensis 12 0.00 0.00 0.00 0.00 0.00 0.00 Chione elsmerensis 13 0.00 0.00 0.00 0.00 0.00 0.00 Chione fernandoensis 14 0.00 0.00 0.00 0.00 0.00 0.00 Chione securis 15 0.00 0.00 0.00 0.00 0.00 0.00 Chlamys sp. 16 0.00 0.00 0.00 0.00 0.00 0.00 Clinocardium meekianum 17 0.00 0.00 0.00 0.00 0.00 0.00 Clinocardium sp. 18 0.00 0.00 0.00 0.00 0.00 0.00 Crassadoma gigantea 19 0.00 0.00 0.00 0.00 0.00 0.00 Crassostrea titan 20 0.00 0.00 0.00 0.00 0.00 0.00 Cuminga californica 21 0.00 0.00 0.00 0.00 0.00 0.00 Cyclocardia ventricosa 22 0.00 0.00 0.00 0.00 17.14 0.00 Dendostrea? vespertina 23 0.00 0.00 0.00 0.00 0.00 0.00 Dosiniaarnoldi 24 0.00 0.00 0.00 0.00 0.00 0.00 Dosiniajacalitosana 25 0.00 0.00 0.00 0.00 0.00 0.00 Dosniasp. 26 0.00 0.00 0.00 0.00 0.00 0.00 Felaninella harfordi 27 0.00 0.00 0.00 0.00 0.00 0.00 Florimetis dombeii 28 0.00 0.00 0.00 0.00 17.14 0.00 Glycymeris grewingki 29 0.00 0.00 0.00 0.00 0.00 0.00 Lucinomaannulatum 30 0.00 0.00 0.00 0.00 0.00 0.00 Lyropecten terminus 31 0.00 0.00 0.00 0.00 0.00 0.00 Macoma affinis plena 32 0.00 0.00 0.00 0.00 2.86 2.78 Macoma affinis plena 33Appendix C C-1

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100700.04 100700.03 100700.02 100700.01 100299.01 051599.01 Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Macoma indentataCarpenter 34 0.00 0.00 0.00 0.00 0.00 0.00 Macoma inquinata 35 0.00 0.00 0.00 0.00 0.00 0.00 Macoma (Heteromacoma) nasuta (Conrad) 36 0.00 0.00 0.00 0.00 0.00 0.00 Macoma cf.M. (Heteromacoma) nasuta (Conrad) 37 0.00 0.00 0.00 0.00 0.00 0.00 Macoma secta 38 0.00 0.00 0.00 0.00 0.00 0.00 Macoma sp. 39 0.00 0.00 0.00 0.00 0.00 0.00 Mactrid 40 0.00 0.00 0.00 0.00 0.00 0.00 Mactromeris hemphilli 41 0.00 0.00 0.00 0.00 0.00 2.78 Modiolus rectus 42 0.00 40.00 47.37 25.00 0.00 0.00 Mya arenaria 43 0.00 0.00 0.00 0.00 0.00 0.00 Mya truncata 44 0.00 0.00 0.00 0.00 0.00 0.00 Mya sp. 45 0.00 0.00 0.00 0.00 5.71 0.00 Mytilus coalingensis 46 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus trossulus 47 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus cf.M.trossulus 48 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus sp. 49 0.00 0.00 0.00 0.00 0.00 0.00 Nuttallianuttalli 50 0.00 0.00 0.00 0.00 0.00 0.00 Oppenheimopectencoalingensis 51 0.00 0.00 0.00 0.00 0.00 0.00 Ostrea atwoodi 52 0.00 0.00 0.00 0.00 0.00 0.00 Ostrea cf.O.atwoodi 53 0.00 0.00 0.00 0.00 0.00 0.00 Pandora punctata 54 0.00 0.00 0.00 0.00 0.00 0.00 Panope estrellana 55 0.00 0.00 0.00 0.00 0.00 0.00 Panope generosa 56 0.00 0.00 0.00 0.00 0.00 0.00 Panope? sp. 57 0.00 0.00 0.00 0.00 0.00 0.00 Patinopecten lohri 58 0.00 0.00 0.00 0.00 0.00 0.00 Patinopecten sp. 59 0.00 0.00 0.00 0.00 0.00 0.00 Pectinid 60 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca cf.P.grata tarda 61 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca staleyi 62 0.00 0.00 0.00 0.00 2.86 0.00 Protothaca staminae 63 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca tennerima 64 0.00 0.00 0.00 25.00 0.00 0.00 Protothaca sp. 65 0.00 0.00 0.00 0.00 0.00 0.00 Psephidia lordi 66Appendix C (Continued) C-2

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100700.04 100700.03 100700.02 100700.01 100299.01 051599.01 Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Psephidia cf.P.lordi(Baird) 67 100.00 60.00 52.63 25.00 51.43 0.00 Pseudocardium densatum 68 0.00 0.00 0.00 0.00 0.00 0.00 Saxidomus nuttalli 69 0.00 0.00 0.00 0.00 0.00 0.00 Saxidomus nuttallilatus 70 0.00 0.00 0.00 0.00 0.00 0.00 Semelefausta 71 0.00 0.00 0.00 0.00 0.00 0.00 Semelerubripicta 72 0.00 0.00 0.00 0.00 0.00 0.00 Semelesp. 73 0.00 0.00 0.00 0.00 0.00 0.00 Solena perrini 74 0.00 0.00 0.00 0.00 0.00 0.00 Solen sicarius 75 0.00 0.00 0.00 0.00 0.00 0.00 Solen cf.S.sicarius 76 0.00 0.00 0.00 0.00 0.00 0.00 Solenid 77 0.00 0.00 0.00 0.00 0.00 0.00 Swiftopecten parmeleei etchegoini (Anderson) 78 0.00 0.00 0.00 0.00 0.00 0.00 ThraciajacalitosanaArnold 79 0.00 0.00 0.00 0.00 0.00 0.00 Tivela trigonalis 80 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardium(Dallocardium) quadrigenerium 81 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardiumcf.T. (Dallocardium) quadrigenerium 82 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardiumsp. 83 0.00 0.00 0.00 0.00 0.00 0.00 Tresus nuttalli 84 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea dentata Gabb 85 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea pilbryi 86 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea sp. 87 0.00 0.00 0.00 0.00 0.00 0.00 Amnicola linginqua 88 0.00 0.00 0.00 0.00 0.00 0.00 Bittiumaspersum 89 0.00 0.00 0.00 0.00 0.00 0.00 Calliostoma coalingensis 90 0.00 0.00 0.00 0.00 0.00 0.00 Calliostoma coalingensis privum 91 0.00 0.00 0.00 0.00 0.00 0.00 Calliostoma sp. 92 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeafilosa 93 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeainornata 94 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeasp. 95 0.00 0.00 0.00 0.00 0.00 0.00 Cancellaria trintoidea 96 0.00 0.00 0.00 0.00 0.00 0.00 Cancellaria sp. 97 0.00 0.00 0.00 0.00 0.00 0.00 Clavus(Clathrodrillia) coalingensis (Arnold) 98 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula adunca 99Appendix C (Continued) C-3

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100700.04 100700.03 100700.02 100700.01 100299.01 051599.01 Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula onyx 100 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula princeps 101 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula sp. 102 0.00 0.00 0.00 0.00 0.00 0.00 Fontellicella longinqua 103 0.00 0.00 0.00 0.00 0.00 0.00 Fluminicola spiralis 104 0.00 0.00 0.00 0.00 0.00 0.00 Fluminicola sp. 105 0.00 0.00 0.00 0.00 0.00 0.00 Forreria carisaensis 106 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria carisaensis mirandaensis 107 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria coalingensis 108 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria magister 109 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria magister munda 110 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria sp. 111 0.00 0.00 0.00 0.00 0.00 0.00 Gonobasis kettelmanensis 112 0.00 0.00 0.00 0.00 0.00 0.00 Litorina mariana 113 0.00 0.00 0.00 0.00 0.00 2.78 Margarita johsoni 114 0.00 0.00 0.00 0.00 0.00 0.00 Mitrellarichthofeni(Gabb) 115 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius (Demondia) californianus (Conrad) 116 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius cf. N.(Demondia) californianus (Conrad) 117 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius coalingensis 118 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius iniquos 119 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius (Caesia)moranianus (Martin) 120 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius sp. 121 0.00 0.00 0.00 0.00 0.00 0.00 Neverita reclusiana 122 0.00 0.00 0.00 25.00 0.00 33.33 Nuccella etchegoinensis 123 0.00 0.00 0.00 0.00 0.00 0.00 Nuccella funkeana 124 0.00 0.00 0.00 0.00 2.86 0.00 Olivella baetica 125 0.00 0.00 0.00 0.00 0.00 55.56 Olivella biplicata 126 0.00 0.00 0.00 0.00 0.00 0.00 Polinices lewsii 127 0.00 0.00 0.00 0.00 0.00 0.00 Pleropurpura festiva(Hinds) 128 0.00 0.00 0.00 0.00 0.00 0.00 Searlesia?sp. 129 0.00 0.00 0.00 0.00 0.00 0.00 Sinumsculpulosum 130 0.00 0.00 0.00 0.00 0.00 0.00 Siphonalia kettelmanensis 131 0.00 0.00 0.00 0.00 0.00 0.00 Thais imperialis 132Appendix C (Continued) C-4

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111800.03 111800.02 111800.01c 111800.01b 111800.01a 111700.01 Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Acila castrensis 1 0.00 0.00 0.00 0.00 0.00 0.00 Adula gruneri 2 0.00 0.00 0.00 0.00 0.00 0.00 Aloidis gibbiformis 3 0.00 0.00 0.00 0.00 0.00 0.00 Amiantis callosa 4 0.00 0.00 0.00 0.00 0.00 0.00 Amiantis communis 5 1.05 0.00 0.88 7.21 15.87 0.00 Anadara trilineata 6 0.00 0.00 0.00 0.00 0.00 0.00 Argopecten circularius eldridgii 7 0.00 0.00 0.00 0.00 0.00 0.00 Argopecten circularius impostor 8 0.00 0.00 0.00 0.00 0.00 0.00 Chacaia ovoidea 9 0.00 0.00 0.00 0.00 0.00 0.00 Chama arcana 10 0.00 0.00 0.00 0.00 0.00 0.00 Chione (Chionopsis) semiplicata 11 0.00 0.00 0.00 0.00 0.00 0.00 Chione coalingensis 12 0.00 0.00 0.00 0.00 0.00 0.00 Chione elsmerensis 13 0.00 0.00 0.00 0.00 0.00 0.00 Chione fernandoensis 14 0.00 0.00 0.00 0.00 0.00 0.00 Chione securis 15 0.00 0.00 0.00 0.00 0.00 0.00 Chlamys sp. 16 1.05 0.00 0.00 0.00 0.00 0.00 Clinocardium meekianum 17 0.00 0.00 0.00 0.00 0.00 1.97 Clinocardium sp. 18 0.00 0.00 0.00 0.00 0.00 0.00 Crassadoma gigantea 19 0.00 0.00 0.00 0.00 0.00 0.00 Crassostrea titan 20 0.00 0.00 0.00 0.00 0.00 0.00 Cuminga californica 21 0.00 0.00 0.00 0.00 0.00 0.00 Cyclocardia ventricosa 22 1.05 0.00 0.00 2.70 3.17 0.00 Dendostrea? vespertina 23 0.00 0.00 0.00 0.00 0.00 0.00 Dosiniaarnoldi 24 0.00 0.00 0.00 0.00 0.00 0.00 Dosiniajacalitosana 25 0.00 0.00 0.00 0.00 0.00 0.00 Dosniasp. 26 0.00 0.00 0.00 0.00 0.00 0.00 Felaninella harfordi 27 0.00 0.00 0.00 0.00 0.00 0.00 Florimetis dombeii 28 1.05 4.00 0.00 0.00 0.00 0.00 Glycymeris grewingki 29 0.00 0.00 0.00 0.00 0.00 0.00 Lucinomaannulatum 30 0.00 0.00 0.00 0.00 0.00 0.00 Lyropecten terminus 31 0.00 0.00 0.00 0.00 0.00 0.00 Macoma affinis plena 32 3.16 0.00 0.00 0.00 0.00 0.00 Macoma affinis plena 33Appendix C (Continued) C-5

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111800.03 111800.02 111800.01c 111800.01b 111800.01a 111700.01 Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Macoma indentataCarpenter 34 0.00 0.00 0.00 0.00 3.17 0.00 Macoma inquinata 35 0.00 0.00 1.75 0.00 1.59 0.00 Macoma (Heteromacoma) nasuta (Conrad) 36 0.00 0.00 0.00 0.00 0.00 0.00 Macoma cf.M. (Heteromacoma) nasuta (Conrad) 37 0.00 0.00 0.00 0.90 0.00 0.00 Macoma secta 38 0.00 0.00 0.00 0.00 0.00 0.00 Macoma sp. 39 0.00 0.00 0.00 0.00 0.00 0.00 Mactrid 40 0.00 0.00 0.00 0.00 0.00 0.00 Mactromeris hemphilli 41 0.00 0.00 0.00 0.00 0.00 0.00 Modiolus rectus 42 0.00 0.00 0.00 0.90 0.00 28.29 Mya arenaria 43 0.00 0.00 0.00 0.00 0.00 0.00 Mya truncata 44 0.00 0.00 0.00 0.00 0.00 0.00 Mya sp. 45 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus coalingensis 46 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus trossulus 47 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus cf.M.trossulus 48 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus sp. 49 0.00 0.00 0.00 0.00 0.00 0.00 Nuttallianuttalli 50 0.00 0.00 0.00 0.00 0.00 0.00 Oppenheimopectencoalingensis 51 0.00 0.00 0.00 0.00 0.00 0.00 Ostrea atwoodi 52 0.00 0.00 0.00 0.00 0.00 0.00 Ostrea cf.O.atwoodi 53 0.00 0.00 0.00 0.00 0.00 0.00 Pandora punctata 54 0.00 0.00 0.00 0.00 0.00 0.00 Panope estrellana 55 0.00 0.00 0.00 0.00 0.00 0.00 Panope generosa 56 0.00 0.00 0.00 0.00 0.00 0.00 Panope? sp. 57 0.00 0.00 0.00 0.00 0.00 0.00 Patinopecten lohri 58 0.00 0.00 0.00 0.00 0.00 0.00 Patinopecten sp. 59 0.00 0.00 0.00 0.00 0.00 0.00 Pectinid 60 0.00 0.00 0.00 0.00 0.00 0.66 Protothaca cf.P.grata tarda 61 0.00 0.00 0.00 19.82 17.46 0.00 Protothaca staleyi 62 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca staminae 63 3.16 0.00 0.00 0.00 0.00 0.00 Protothaca tennerima 64 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca sp. 65 28.42 0.00 0.00 0.00 0.00 0.00 Psephidia lordi 66Appendix C (Continued) C-6

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111800.03 111800.02 111800.01c 111800.01b 111800.01a 111700.01 Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Psephidia cf.P.lordi(Baird) 67 10.53 72.00 94.74 19.82 20.63 0.00 Pseudocardium densatum 68 0.00 0.00 0.00 0.00 0.00 0.00 Saxidomus nuttalli 69 0.00 0.00 0.00 0.00 0.00 0.00 Saxidomus nuttallilatus 70 0.00 0.00 0.00 0.00 0.00 0.00 Semelefausta 71 0.00 0.00 0.00 0.00 0.00 0.00 Semelerubripicta 72 0.00 0.00 0.00 0.00 0.00 0.00 Semelesp. 73 0.00 0.00 0.00 0.00 3.17 0.00 Solena perrini 74 8.42 0.00 2.63 9.91 0.00 0.00 Solen sicarius 75 0.00 0.00 0.00 0.00 0.00 0.00 Solen cf.S.sicarius 76 0.00 0.00 0.00 0.00 0.00 0.66 Solenid 77 0.00 0.00 0.00 0.00 0.00 0.00 Swiftopecten parmeleei etchegoini (Anderson) 78 0.00 0.00 0.00 0.00 0.00 0.00 ThraciajacalitosanaArnold 79 0.00 0.00 0.00 0.00 0.00 0.00 Tivela trigonalis 80 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardium(Dallocardium) quadrigenerium 81 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardiumcf.T. (Dallocardium) quadrigenerium 82 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardiumsp. 83 0.00 0.00 0.00 0.00 0.00 0.00 Tresus nuttalli 84 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea dentata Gabb 85 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea pilbryi 86 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea sp. 87 0.00 0.00 0.00 18.92 14.29 0.00 Amnicola linginqua 88 6.32 0.00 0.00 9.01 14.29 0.00 Bittiumaspersum 89 0.00 0.00 0.00 0.00 0.00 0.00 Calliostoma coalingensis 90 2.11 0.00 0.00 0.00 0.00 0.00 Calliostoma coalingensis privum 91 0.00 0.00 0.00 0.00 0.00 0.00 Calliostoma sp. 92 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeafilosa 93 0.00 0.00 0.00 0.00 0.00 61.84 Calyptraeainornata 94 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeasp. 95 0.00 0.00 0.00 0.00 0.00 0.00 Cancellaria trintoidea 96 0.00 0.00 0.00 0.00 0.00 0.00 Cancellaria sp. 97 0.00 0.00 0.00 2.70 0.00 0.00 Clavus(Clathrodrillia) coalingensis (Arnold) 98 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula adunca 99Appendix C (Continued) C-7

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111800.03 111800.02 111800.01c 111800.01b 111800.01a 111700.01 Species no. 0.00 0.00 0.00 0.00 0.00 6.58 Crepidula onyx 100 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula princeps 101 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula sp. 102 0.00 0.00 0.00 2.70 0.00 0.00 Fontellicella longinqua 103 0.00 0.00 0.00 0.00 0.00 0.00 Fluminicola spiralis 104 0.00 0.00 0.00 0.00 0.00 0.00 Fluminicola sp. 105 0.00 0.00 0.00 0.00 0.00 0.00 Forreria carisaensis 106 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria carisaensis mirandaensis 107 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria coalingensis 108 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria magister 109 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria magister munda 110 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria sp. 111 0.00 0.00 0.00 0.00 4.76 0.00 Gonobasis kettelmanensis 112 0.00 4.00 0.00 2.70 0.00 0.00 Litorina mariana 113 0.00 0.00 0.00 0.00 0.00 0.00 Margarita johsoni 114 0.00 0.00 0.00 2.70 0.00 0.00 Mitrellarichthofeni(Gabb) 115 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius (Demondia) californianus (Conrad) 116 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius cf. N.(Demondia) californianus (Conrad) 117 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius coalingensis 118 6.32 0.00 0.00 0.00 0.00 0.00 Nassarius iniquos 119 0.00 16.00 0.00 0.00 0.00 0.00 Nassarius (Caesia)moranianus (Martin) 120 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius sp. 121 26.32 0.00 0.00 0.00 0.00 0.00 Neverita reclusiana 122 0.00 0.00 0.00 0.00 0.00 0.00 Nuccella etchegoinensis 123 0.00 0.00 0.00 0.00 0.00 0.00 Nuccella funkeana 124 0.00 4.00 0.00 0.00 0.00 0.00 Olivella baetica 125 0.00 0.00 0.00 0.00 0.00 0.00 Olivella biplicata 126 0.00 0.00 0.00 0.00 1.59 0.00 Polinices lewsii 127 0.00 0.00 0.00 0.00 0.00 0.00 Pleropurpura festiva(Hinds) 128 0.00 0.00 0.00 0.00 0.00 0.00 Searlesia?sp. 129 0.00 0.00 0.00 0.00 0.00 0.00 Sinumsculpulosum 130 1.05 0.00 0.00 0.00 0.00 0.00 Siphonalia kettelmanensis 131 0.00 0.00 0.00 0.00 0.00 0.00 Thais imperialis 132Appendix C (Continued) C-8

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121500.03 121500.02c 121500.02b 121500.02a 121500.01b 121500.01a Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Acila castrensis 1 0.00 0.00 0.00 0.00 0.00 0.00 Adula gruneri 2 0.00 0.00 0.00 0.00 0.00 0.00 Aloidis gibbiformis 3 0.00 0.00 0.00 0.00 0.00 0.00 Amiantis callosa 4 0.00 0.00 0.00 0.00 0.00 0.00 Amiantis communis 5 0.00 0.00 0.00 0.00 17.65 1.89 Anadara trilineata 6 0.00 0.00 0.00 0.00 0.00 0.00 Argopecten circularius eldridgii 7 0.00 0.00 0.00 0.00 0.00 0.00 Argopecten circularius impostor 8 0.00 0.00 0.00 0.00 0.00 0.00 Chacaia ovoidea 9 0.00 0.00 0.00 0.00 0.00 0.00 Chama arcana 10 0.00 0.00 0.00 0.00 0.00 0.00 Chione (Chionopsis) semiplicata 11 0.00 0.00 0.00 0.00 0.00 0.00 Chione coalingensis 12 0.00 0.00 0.00 0.00 0.00 0.00 Chione elsmerensis 13 0.00 0.00 0.00 0.00 0.00 0.00 Chione fernandoensis 14 0.00 0.00 0.00 0.00 0.00 0.00 Chione securis 15 0.00 0.00 0.00 0.00 0.00 0.00 Chlamys sp. 16 0.00 0.00 0.00 0.00 0.00 0.00 Clinocardium meekianum 17 0.00 0.00 0.00 0.00 0.00 0.00 Clinocardium sp. 18 0.00 0.00 0.00 0.00 0.00 0.00 Crassadoma gigantea 19 0.00 0.00 0.00 0.00 0.00 0.00 Crassostrea titan 20 0.00 0.00 0.00 0.00 5.88 0.00 Cuminga californica 21 0.00 0.00 0.00 0.00 0.00 0.00 Cyclocardia ventricosa 22 0.00 0.00 0.00 0.00 0.00 0.00 Dendostrea? vespertina 23 0.00 0.00 0.00 0.00 0.00 0.00 Dosiniaarnoldi 24 0.00 0.00 0.00 0.00 0.00 0.00 Dosiniajacalitosana 25 0.00 0.00 0.00 0.00 0.00 0.00 Dosniasp. 26 0.00 0.00 0.00 0.00 0.00 0.00 Felaninella harfordi 27 0.00 0.00 0.00 0.00 0.00 0.00 Florimetis dombeii 28 0.00 0.00 0.00 90.63 5.88 3.77 Glycymeris grewingki 29 0.00 0.00 0.00 0.00 0.00 0.00 Lucinomaannulatum 30 0.00 0.00 0.00 0.00 0.00 1.89 Lyropecten terminus 31 0.00 0.00 0.00 0.00 0.00 0.00 Macoma affinis plena 32 0.00 0.00 0.00 0.00 11.76 0.00 Macoma affinis plena 33Appendix C (Continued) C-9

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121500.03 121500.02c 121500.02b 121500.02a 121500.01b 121500.01a Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Macoma indentataCarpenter 34 0.00 0.00 0.00 0.00 0.00 0.00 Macoma inquinata 35 0.00 0.00 0.00 0.00 0.00 0.00 Macoma (Heteromacoma) nasuta (Conrad) 36 0.00 0.00 0.00 0.00 0.00 0.00 Macoma cf.M. (Heteromacoma) nasuta (Conrad) 37 0.00 0.00 0.00 0.00 0.00 3.77 Macoma secta 38 0.00 0.00 0.00 0.00 0.00 0.00 Macoma sp. 39 0.00 0.00 0.00 0.00 0.00 0.00 Mactrid 40 0.00 0.00 0.00 0.00 0.00 3.77 Mactromeris hemphilli 41 0.00 0.00 0.00 0.00 0.00 0.00 Modiolus rectus 42 0.00 0.00 0.00 0.00 0.00 0.00 Mya arenaria 43 0.00 0.00 0.00 0.00 0.00 0.00 Mya truncata 44 0.00 0.00 0.00 0.00 0.00 0.00 Mya sp. 45 0.00 0.00 0.00 0.00 5.88 0.00 Mytilus coalingensis 46 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus trossulus 47 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus cf.M.trossulus 48 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus sp. 49 0.00 0.00 0.00 0.00 0.00 0.00 Nuttallianuttalli 50 0.00 0.00 0.00 0.00 0.00 0.00 Oppenheimopectencoalingensis 51 0.00 0.00 0.00 0.00 0.00 0.00 Ostrea atwoodi 52 0.00 0.00 0.00 0.00 0.00 0.00 Ostrea cf.O.atwoodi 53 0.00 0.00 0.00 0.00 0.00 0.00 Pandora punctata 54 0.00 0.00 0.00 0.00 0.00 0.00 Panope estrellana 55 0.00 0.00 0.00 0.00 0.00 0.00 Panope generosa 56 0.00 0.00 0.00 0.00 0.00 0.00 Panope? sp. 57 0.00 0.00 0.00 0.00 0.00 0.00 Patinopecten lohri 58 0.00 0.00 0.00 0.00 0.00 0.00 Patinopecten sp. 59 0.00 0.00 0.00 0.00 0.00 0.00 Pectinid 60 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca cf.P.grata tarda 61 0.00 0.00 0.00 3.13 0.00 1.89 Protothaca staleyi 62 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca staminae 63 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca tennerima 64 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca sp. 65 0.00 0.00 0.00 0.00 0.00 0.00 Psephidia lordi 66Appendix C (Continued) C-10

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121500.03 121500.02c 121500.02b 121500.02a 121500.01b 121500.01a Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Psephidia cf.P.lordi(Baird) 67 50.00 100.00 100.00 1.56 0.00 58.49 Pseudocardium densatum 68 0.00 0.00 0.00 0.00 0.00 0.00 Saxidomus nuttalli 69 0.00 0.00 0.00 0.00 0.00 0.00 Saxidomus nuttallilatus 70 0.00 0.00 0.00 0.00 0.00 0.00 Semelefausta 71 0.00 0.00 0.00 0.00 0.00 0.00 Semelerubripicta 72 0.00 0.00 0.00 0.00 0.00 0.00 Semelesp. 73 0.00 0.00 0.00 0.00 0.00 0.00 Solena perrini 74 0.00 0.00 0.00 0.00 0.00 0.00 Solen sicarius 75 0.00 0.00 0.00 0.00 0.00 0.00 Solen cf.S.sicarius 76 0.00 0.00 0.00 0.00 0.00 0.00 Solenid 77 0.00 0.00 0.00 0.00 0.00 0.00 Swiftopecten parmeleei etchegoini (Anderson) 78 0.00 0.00 0.00 0.00 0.00 0.00 ThraciajacalitosanaArnold 79 0.00 0.00 0.00 0.00 0.00 0.00 Tivela trigonalis 80 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardium(Dallocardium) quadrigenerium 81 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardiumcf.T. (Dallocardium) quadrigenerium 82 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardiumsp. 83 9.09 0.00 0.00 0.00 11.76 1.89 Tresus nuttalli 84 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea dentata Gabb 85 0.00 0.00 0.00 0.00 5.88 0.00 Zirfaea pilbryi 86 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea sp. 87 0.00 0.00 0.00 0.00 0.00 0.00 Amnicola linginqua 88 0.00 0.00 0.00 0.00 0.00 1.89 Bittiumaspersum 89 18.18 0.00 0.00 0.00 0.00 13.21 Calliostoma coalingensis 90 0.00 0.00 0.00 0.00 5.88 0.00 Calliostoma coalingensis privum 91 0.00 0.00 0.00 0.00 0.00 0.00 Calliostoma sp. 92 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeafilosa 93 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeainornata 94 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeasp. 95 0.00 0.00 0.00 0.00 0.00 0.00 Cancellaria trintoidea 96 0.00 0.00 0.00 0.00 0.00 0.00 Cancellaria sp. 97 0.00 0.00 0.00 0.00 0.00 0.00 Clavus(Clathrodrillia) coalingensis (Arnold) 98 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula adunca 99Appendix C (Continued) C-11

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121500.03 121500.02c 121500.02b 121500.02a 121500.01b 121500.01a Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula onyx 100 0.00 0.00 0.00 0.00 0.00 1.89 Crepidula princeps 101 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula sp. 102 0.00 0.00 0.00 0.00 0.00 0.00 Fontellicella longinqua 103 0.00 0.00 0.00 0.00 0.00 0.00 Fluminicola spiralis 104 0.00 0.00 0.00 0.00 0.00 0.00 Fluminicola sp. 105 0.00 0.00 0.00 0.00 0.00 0.00 Forreria carisaensis 106 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria carisaensis mirandaensis 107 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria coalingensis 108 4.55 0.00 0.00 0.00 0.00 0.00 Forrerria magister 109 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria magister munda 110 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria sp. 111 0.00 0.00 0.00 0.00 0.00 0.00 Gonobasis kettelmanensis 112 0.00 0.00 0.00 0.00 0.00 0.00 Litorina mariana 113 0.00 0.00 0.00 0.00 0.00 0.00 Margarita johsoni 114 0.00 0.00 0.00 0.00 0.00 0.00 Mitrellarichthofeni(Gabb) 115 0.00 0.00 0.00 0.00 29.41 0.00 Nassarius (Demondia) californianus (Conrad) 116 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius cf. N.(Demondia) californianus (Conrad) 117 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius coalingensis 118 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius iniquos 119 4.55 0.00 0.00 4.69 0.00 0.00 Nassarius (Caesia)moranianus (Martin) 120 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius sp. 121 0.00 0.00 0.00 0.00 0.00 3.77 Neverita reclusiana 122 4.55 0.00 0.00 0.00 0.00 0.00 Nuccella etchegoinensis 123 0.00 0.00 0.00 0.00 0.00 0.00 Nuccella funkeana 124 4.55 0.00 0.00 0.00 0.00 1.89 Olivella baetica 125 0.00 0.00 0.00 0.00 0.00 0.00 Olivella biplicata 126 4.55 0.00 0.00 0.00 0.00 0.00 Polinices lewsii 127 0.00 0.00 0.00 0.00 0.00 0.00 Pleropurpura festiva(Hinds) 128 0.00 0.00 0.00 0.00 0.00 0.00 Searlesia?sp. 129 0.00 0.00 0.00 0.00 0.00 0.00 Sinumsculpulosum 130 0.00 0.00 0.00 0.00 0.00 0.00 Siphonalia kettelmanensis 131 0.00 0.00 0.00 0.00 0.00 0.00 Thais imperialis 132Appendix C (Continued) C-12

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101301.02a 101301.01c 061001.01 060701.01 021701.02 021701.01 Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Acila castrensis 1 0.00 0.00 0.00 0.00 0.00 0.00 Adula gruneri 2 0.00 0.00 0.00 0.00 0.00 0.00 Aloidis gibbiformis 3 0.00 0.00 0.00 0.00 0.00 0.00 Amiantis callosa 4 0.00 0.00 0.00 0.00 0.00 0.00 Amiantis communis 5 0.00 6.67 0.00 0.00 0.00 0.00 Anadara trilineata 6 0.00 0.00 0.00 87.18 0.00 0.00 Argopecten circularius eldridgii 7 0.00 0.00 0.00 5.13 0.00 0.00 Argopecten circularius impostor 8 0.00 0.00 0.00 0.00 0.00 0.00 Chacaia ovoidea 9 0.00 0.00 0.00 0.00 0.00 0.00 Chama arcana 10 0.00 0.00 0.00 0.00 0.00 0.00 Chione (Chionopsis) semiplicata 11 0.00 0.00 0.00 0.00 0.00 0.00 Chione coalingensis 12 0.00 0.00 0.00 0.00 0.00 0.00 Chione elsmerensis 13 0.00 0.00 0.00 0.00 0.00 0.00 Chione fernandoensis 14 0.00 0.00 0.00 0.00 0.00 0.00 Chione securis 15 0.00 0.00 0.00 0.00 0.00 0.00 Chlamys sp. 16 0.00 0.00 0.00 0.00 0.00 6.82 Clinocardium meekianum 17 0.00 0.00 0.00 0.00 0.00 0.00 Clinocardium sp. 18 0.00 0.00 0.00 0.00 0.00 0.00 Crassadoma gigantea 19 0.00 0.00 0.00 0.00 0.00 0.00 Crassostrea titan 20 0.00 0.00 0.00 0.00 0.00 0.00 Cuminga californica 21 0.00 0.00 0.00 0.00 0.00 0.00 Cyclocardia ventricosa 22 0.00 9.33 0.00 0.00 0.00 2.27 Dendostrea? vespertina 23 0.00 0.00 0.00 0.00 0.00 0.00 Dosiniaarnoldi 24 0.00 0.00 0.00 0.00 0.00 0.00 Dosiniajacalitosana 25 0.00 0.00 0.00 0.00 0.00 0.00 Dosniasp. 26 0.00 0.00 0.00 0.00 0.00 0.00 Felaninella harfordi 27 0.00 0.00 0.00 0.00 0.00 0.00 Florimetis dombeii 28 0.00 0.00 0.00 0.00 0.00 5.68 Glycymeris grewingki 29 0.00 1.33 0.00 0.00 0.00 0.00 Lucinomaannulatum 30 0.00 0.00 0.00 7.69 0.00 0.00 Lyropecten terminus 31 0.00 0.00 0.00 0.00 0.00 0.00 Macoma affinis plena 32 0.00 0.00 0.00 0.00 5.77 0.00 Macoma affinis plena 33Appendix C (Continued) C-13

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101301.02a 101301.01c 061001.01 060701.01 021701.02 021701.01 Species no. 0.00 0.00 0.00 0.00 0.00 2.27 Macoma indentataCarpenter 34 0.00 0.00 19.43 0.00 0.00 0.00 Macoma inquinata 35 0.00 5.33 0.00 0.00 0.00 0.00 Macoma (Heteromacoma) nasuta (Conrad) 36 0.00 0.00 0.00 0.00 0.00 0.00 Macoma cf.M. (Heteromacoma) nasuta (Conrad) 37 0.00 0.00 0.00 0.00 0.00 0.00 Macoma secta 38 0.00 0.00 0.00 0.00 0.00 0.00 Macoma sp. 39 0.00 0.00 0.00 0.00 0.00 0.00 Mactrid 40 0.00 0.00 0.00 0.00 0.00 0.00 Mactromeris hemphilli 41 0.00 0.00 0.00 0.00 0.00 0.00 Modiolus rectus 42 3.57 0.00 32.00 0.00 0.00 6.82 Mya arenaria 43 0.00 0.00 4.00 0.00 0.00 0.00 Mya truncata 44 0.00 0.00 0.00 0.00 0.00 0.00 Mya sp. 45 0.00 0.00 0.00 0.00 48.08 1.14 Mytilus coalingensis 46 0.00 0.00 5.71 0.00 0.00 0.00 Mytilus trossulus 47 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus cf.M.trossulus 48 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus sp. 49 0.00 0.00 0.00 0.00 0.00 0.00 Nuttallianuttalli 50 0.00 0.00 0.00 0.00 0.00 0.00 Oppenheimopectencoalingensis 51 0.00 0.00 0.00 0.00 0.00 0.00 Ostrea atwoodi 52 0.00 0.00 0.00 0.00 0.00 0.00 Ostrea cf.O.atwoodi 53 0.00 0.00 0.00 0.00 1.92 0.00 Pandora punctata 54 0.00 0.00 0.00 0.00 0.00 0.00 Panope estrellana 55 0.00 0.00 0.00 0.00 0.00 0.00 Panope generosa 56 0.00 0.00 0.00 0.00 0.00 0.00 Panope? sp. 57 0.00 0.00 0.00 0.00 0.00 0.00 Patinopecten lohri 58 0.00 0.00 0.00 0.00 0.00 0.00 Patinopecten sp. 59 0.00 0.00 0.00 0.00 0.00 0.00 Pectinid 60 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca cf.P.grata tarda 61 10.71 0.00 0.00 0.00 0.00 0.00 Protothaca staleyi 62 0.00 0.00 0.00 0.00 0.00 3.41 Protothaca staminae 63 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca tennerima 64 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca sp. 65 0.00 2.67 0.00 0.00 0.00 5.68 Psephidia lordi 66Appendix C (Continued) C-14

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101301.02a 101301.01c 061001.01 060701.01 021701.02 021701.01 Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Psephidia cf.P.lordi(Baird) 67 85.71 41.33 0.00 0.00 0.00 19.32 Pseudocardium densatum 68 0.00 0.00 0.00 0.00 0.00 0.00 Saxidomus nuttalli 69 0.00 0.00 0.00 0.00 0.00 0.00 Saxidomus nuttallilatus 70 0.00 0.00 0.00 0.00 0.00 0.00 Semelefausta 71 0.00 0.00 0.00 0.00 0.00 0.00 Semelerubripicta 72 0.00 0.00 0.00 0.00 0.00 0.00 Semelesp. 73 0.00 0.00 5.14 0.00 0.00 9.09 Solena perrini 74 0.00 0.00 0.00 0.00 0.00 0.00 Solen sicarius 75 0.00 0.00 0.00 0.00 0.00 0.00 Solen cf.S.sicarius 76 0.00 0.00 0.00 0.00 0.00 0.00 Solenid 77 0.00 0.00 0.00 0.00 0.00 0.00 Swiftopecten parmeleei etchegoini (Anderson) 78 0.00 0.00 0.00 0.00 0.00 0.00 ThraciajacalitosanaArnold 79 0.00 0.00 0.00 0.00 0.00 0.00 Tivela trigonalis 80 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardium(Dallocardium) quadrigenerium 81 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardiumcf.T. (Dallocardium) quadrigenerium 82 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardiumsp. 83 0.00 0.00 0.00 0.00 0.00 0.00 Tresus nuttalli 84 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea dentata Gabb 85 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea pilbryi 86 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea sp. 87 0.00 0.00 0.00 0.00 0.00 0.00 Amnicola linginqua 88 0.00 28.00 0.00 0.00 1.92 0.00 Bittiumaspersum 89 0.00 0.00 0.00 0.00 0.00 0.00 Calliostoma coalingensis 90 0.00 0.00 0.00 0.00 0.00 30.68 Calliostoma coalingensis privum 91 0.00 0.00 0.00 0.00 0.00 0.00 Calliostoma sp. 92 0.00 0.00 22.29 0.00 0.00 0.00 Calyptraeafilosa 93 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeainornata 94 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeasp. 95 0.00 0.00 0.00 0.00 0.00 0.00 Cancellaria trintoidea 96 0.00 0.00 0.00 0.00 0.00 0.00 Cancellaria sp. 97 0.00 0.00 0.00 0.00 0.00 0.00 Clavus(Clathrodrillia) coalingensis (Arnold) 98 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula adunca 99Appendix C (Continued) C-15

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101301.02a 101301.01c 061001.01 060701.01 021701.02 021701.01 Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula onyx 100 0.00 0.00 0.00 0.00 42.31 4.55 Crepidula princeps 101 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula sp. 102 0.00 0.00 0.00 0.00 0.00 0.00 Fontellicella longinqua 103 0.00 0.00 0.00 0.00 0.00 0.00 Fluminicola spiralis 104 0.00 1.33 0.00 0.00 0.00 0.00 Fluminicola sp. 105 0.00 0.00 0.00 0.00 0.00 0.00 Forreria carisaensis 106 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria carisaensis mirandaensis 107 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria coalingensis 108 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria magister 109 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria magister munda 110 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria sp. 111 0.00 1.33 0.00 0.00 0.00 0.00 Gonobasis kettelmanensis 112 0.00 0.00 11.43 0.00 0.00 0.00 Litorina mariana 113 0.00 0.00 0.00 0.00 0.00 0.00 Margarita johsoni 114 0.00 0.00 0.00 0.00 0.00 0.00 Mitrellarichthofeni(Gabb) 115 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius (Demondia) californianus (Conrad) 116 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius cf. N.(Demondia) californianus (Conrad) 117 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius coalingensis 118 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius iniquos 119 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius (Caesia)moranianus (Martin) 120 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius sp. 121 0.00 2.67 0.00 0.00 0.00 2.27 Neverita reclusiana 122 0.00 0.00 0.00 0.00 0.00 0.00 Nuccella etchegoinensis 123 0.00 0.00 0.00 0.00 0.00 0.00 Nuccella funkeana 124 0.00 0.00 0.00 0.00 0.00 0.00 Olivella baetica 125 0.00 0.00 0.00 0.00 0.00 0.00 Olivella biplicata 126 0.00 0.00 0.00 0.00 0.00 0.00 Polinices lewsii 127 0.00 0.00 0.00 0.00 0.00 0.00 Pleropurpura festiva(Hinds) 128 0.00 0.00 0.00 0.00 0.00 0.00 Searlesia?sp. 129 0.00 0.00 0.00 0.00 0.00 0.00 Sinumsculpulosum 130 0.00 0.00 0.00 0.00 0.00 0.00 Siphonalia kettelmanensis 131 0.00 0.00 0.00 0.00 0.00 0.00 Thais imperialis 132Appendix C (Continued) C-16

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101301.08d 101301.08c 101301.08b 101301.08a 101301.06 101301.05a Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Acila castrensis 1 0.00 0.00 0.00 0.00 0.00 0.00 Adula gruneri 2 0.00 0.00 0.00 0.00 0.00 0.00 Aloidis gibbiformis 3 0.00 0.00 0.00 0.00 0.00 0.00 Amiantis callosa 4 0.00 0.00 0.00 0.00 0.00 0.00 Amiantis communis 5 0.00 0.00 0.00 0.00 24.00 0.00 Anadara trilineata 6 0.00 0.00 0.00 0.00 0.00 0.00 Argopecten circularius eldridgii 7 0.00 0.00 0.00 0.00 0.00 0.00 Argopecten circularius impostor 8 0.00 0.00 0.00 0.00 0.00 0.00 Chacaia ovoidea 9 0.00 0.00 0.00 0.00 0.00 0.00 Chama arcana 10 0.00 0.00 0.00 0.00 0.00 0.00 Chione (Chionopsis) semiplicata 11 0.00 0.00 0.00 0.00 0.00 0.00 Chione coalingensis 12 0.00 0.00 0.00 0.00 0.00 0.00 Chione elsmerensis 13 0.00 0.00 0.00 0.00 0.00 0.00 Chione fernandoensis 14 0.00 0.00 0.00 2.00 0.00 0.00 Chione securis 15 0.00 0.00 0.00 0.00 0.00 0.00 Chlamys sp. 16 0.00 0.00 0.00 0.00 0.00 0.00 Clinocardium meekianum 17 0.00 0.00 0.00 0.00 0.00 0.00 Clinocardium sp. 18 0.00 0.00 0.00 0.00 0.00 0.00 Crassadoma gigantea 19 0.00 0.00 0.00 0.00 0.00 0.00 Crassostrea titan 20 0.00 0.00 0.00 0.00 0.00 0.00 Cuminga californica 21 0.00 0.00 0.00 0.00 0.00 0.00 Cyclocardia ventricosa 22 0.00 0.00 0.00 2.00 0.00 0.00 Dendostrea? vespertina 23 0.00 0.00 0.00 0.00 0.00 0.00 Dosiniaarnoldi 24 0.00 0.00 0.00 0.00 0.00 0.00 Dosiniajacalitosana 25 0.00 0.00 0.00 0.00 0.00 0.00 Dosniasp. 26 0.00 0.00 0.00 0.00 0.00 0.00 Felaninella harfordi 27 0.00 0.00 0.00 0.00 0.00 0.00 Florimetis dombeii 28 0.00 0.00 0.00 4.00 0.00 0.00 Glycymeris grewingki 29 0.00 0.00 0.00 0.00 0.00 0.00 Lucinomaannulatum 30 0.00 0.00 0.00 0.00 0.00 0.00 Lyropecten terminus 31 0.00 0.00 0.00 0.00 0.00 0.00 Macoma affinis plena 32 0.00 0.00 0.00 0.00 0.00 0.00 Macoma affinis plena 33Appendix C (Continued) C-17

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101301.08d 101301.08c 101301.08b 101301.08a 101301.06 101301.05a Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Macoma indentataCarpenter 34 0.00 0.00 0.00 0.00 0.00 0.00 Macoma inquinata 35 0.00 2.63 7.14 0.00 0.00 0.00 Macoma (Heteromacoma) nasuta (Conrad) 36 0.00 0.00 0.00 0.00 0.00 0.00 Macoma cf.M. (Heteromacoma) nasuta (Conrad) 37 0.00 0.00 0.00 0.00 0.00 0.00 Macoma secta 38 0.00 0.00 0.00 0.00 0.00 0.00 Macoma sp. 39 0.00 0.00 0.00 0.00 0.00 0.00 Mactrid 40 0.00 0.00 0.00 0.00 0.00 0.00 Mactromeris hemphilli 41 0.00 0.00 0.00 0.00 20.00 0.00 Modiolus rectus 42 0.00 2.63 17.86 4.00 8.00 0.00 Mya arenaria 43 0.00 0.00 0.00 0.00 0.00 0.00 Mya truncata 44 0.00 0.00 0.00 0.00 0.00 0.00 Mya sp. 45 0.00 0.00 0.00 2.00 0.00 0.00 Mytilus coalingensis 46 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus trossulus 47 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus cf.M.trossulus 48 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus sp. 49 0.00 0.00 0.00 0.00 0.00 0.00 Nuttallianuttalli 50 0.00 0.00 0.00 0.00 0.00 0.00 Oppenheimopectencoalingensis 51 0.00 0.00 0.00 0.00 0.00 0.00 Ostrea atwoodi 52 0.00 0.00 0.00 0.00 0.00 0.00 Ostrea cf.O.atwoodi 53 0.00 0.00 0.00 0.00 0.00 0.00 Pandora punctata 54 0.00 0.00 0.00 0.00 0.00 0.00 Panope estrellana 55 0.00 0.00 0.00 0.00 0.00 0.00 Panope generosa 56 0.00 0.00 0.00 0.00 0.00 0.00 Panope? sp. 57 0.00 0.00 0.00 0.00 0.00 0.00 Patinopecten lohri 58 0.00 0.00 0.00 0.00 0.00 0.00 Patinopecten sp. 59 0.00 0.00 0.00 0.00 0.00 0.00 Pectinid 60 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca cf.P.grata tarda 61 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca staleyi 62 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca staminae 63 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca tennerima 64 7.69 0.00 0.00 0.00 0.00 0.00 Protothaca sp. 65 0.00 0.00 0.00 0.00 0.00 0.00 Psephidia lordi 66Appendix C (Continued) C-18

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101301.08d 101301.08c 101301.08b 101301.08a 101301.06 101301.05a Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Psephidia cf.P.lordi(Baird) 67 30.77 94.74 57.14 58.00 0.00 80.00 Pseudocardium densatum 68 0.00 0.00 0.00 2.00 0.00 0.00 Saxidomus nuttalli 69 0.00 0.00 0.00 0.00 0.00 0.00 Saxidomus nuttallilatus 70 0.00 0.00 0.00 0.00 0.00 0.00 Semelefausta 71 0.00 0.00 0.00 0.00 0.00 0.00 Semelerubripicta 72 0.00 0.00 0.00 0.00 0.00 0.00 Semelesp. 73 0.00 0.00 0.00 0.00 0.00 0.00 Solena perrini 74 7.69 0.00 0.00 0.00 0.00 0.00 Solen sicarius 75 0.00 0.00 0.00 0.00 0.00 0.00 Solen cf.S.sicarius 76 0.00 0.00 0.00 0.00 0.00 0.00 Solenid 77 0.00 0.00 0.00 0.00 0.00 0.00 Swiftopecten parmeleei etchegoini (Anderson) 78 0.00 0.00 0.00 0.00 0.00 0.00 ThraciajacalitosanaArnold 79 0.00 0.00 0.00 0.00 0.00 0.00 Tivela trigonalis 80 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardium(Dallocardium) quadrigenerium 81 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardiumcf.T. (Dallocardium) quadrigenerium 82 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardiumsp. 83 0.00 0.00 0.00 0.00 0.00 0.00 Tresus nuttalli 84 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea dentata Gabb 85 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea pilbryi 86 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea sp. 87 0.00 0.00 0.00 0.00 0.00 0.00 Amnicola linginqua 88 23.08 0.00 0.00 0.00 0.00 0.00 Bittiumaspersum 89 0.00 0.00 0.00 0.00 0.00 0.00 Calliostoma coalingensis 90 0.00 0.00 0.00 0.00 0.00 0.00 Calliostoma coalingensis privum 91 0.00 0.00 0.00 0.00 0.00 0.00 Calliostoma sp. 92 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeafilosa 93 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeainornata 94 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeasp. 95 0.00 0.00 0.00 0.00 0.00 0.00 Cancellaria trintoidea 96 0.00 0.00 0.00 0.00 0.00 0.00 Cancellaria sp. 97 0.00 0.00 0.00 2.00 0.00 0.00 Clavus(Clathrodrillia) coalingensis (Arnold) 98 23.08 0.00 0.00 0.00 0.00 0.00 Crepidula adunca 99Appendix C (Continued) C-19

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101301.08d 101301.08c 101301.08b 101301.08a 101301.06 101301.05a Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula onyx 100 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula princeps 101 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula sp. 102 0.00 0.00 0.00 6.00 0.00 0.00 Fontellicella longinqua 103 0.00 0.00 0.00 0.00 0.00 0.00 Fluminicola spiralis 104 0.00 0.00 0.00 0.00 0.00 0.00 Fluminicola sp. 105 0.00 0.00 0.00 0.00 0.00 0.00 Forreria carisaensis 106 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria carisaensis mirandaensis 107 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria coalingensis 108 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria magister 109 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria magister munda 110 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria sp. 111 0.00 0.00 0.00 0.00 0.00 0.00 Gonobasis kettelmanensis 112 0.00 0.00 0.00 0.00 0.00 0.00 Litorina mariana 113 0.00 0.00 0.00 0.00 0.00 0.00 Margarita johsoni 114 7.69 0.00 7.14 0.00 0.00 0.00 Mitrellarichthofeni(Gabb) 115 0.00 0.00 0.00 16.00 0.00 0.00 Nassarius (Demondia) californianus (Conrad) 116 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius cf. N.(Demondia) californianus (Conrad) 117 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius coalingensis 118 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius iniquos 119 0.00 0.00 10.71 0.00 0.00 0.00 Nassarius (Caesia)moranianus (Martin) 120 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius sp. 121 0.00 0.00 0.00 0.00 44.00 20.00 Neverita reclusiana 122 0.00 0.00 0.00 0.00 0.00 0.00 Nuccella etchegoinensis 123 0.00 0.00 0.00 0.00 0.00 0.00 Nuccella funkeana 124 0.00 0.00 0.00 0.00 4.00 0.00 Olivella baetica 125 0.00 0.00 0.00 0.00 0.00 0.00 Olivella biplicata 126 0.00 0.00 0.00 2.00 0.00 0.00 Polinices lewsii 127 0.00 0.00 0.00 0.00 0.00 0.00 Pleropurpura festiva(Hinds) 128 0.00 0.00 0.00 0.00 0.00 0.00 Searlesia?sp. 129 0.00 0.00 0.00 0.00 0.00 0.00 Sinumsculpulosum 130 0.00 0.00 0.00 0.00 0.00 0.00 Siphonalia kettelmanensis 131 0.00 0.00 0.00 0.00 0.00 0.00 Thais imperialis 132Appendix C (Continued) C-20

PAGE 313

052802.06b 052802.05 052802.04 030202.06 121401.03 121401.01a Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Acila castrensis 1 0.00 0.00 0.00 0.00 0.00 0.00 Adula gruneri 2 0.00 0.00 0.00 0.00 0.00 0.00 Aloidis gibbiformis 3 0.00 0.00 0.00 0.00 0.00 0.00 Amiantis callosa 4 0.00 0.00 0.00 0.00 0.00 0.00 Amiantis communis 5 0.00 3.03 0.00 0.00 0.00 0.00 Anadara trilineata 6 0.00 0.00 0.00 0.00 0.00 0.00 Argopecten circularius eldridgii 7 0.00 0.00 0.00 0.00 0.00 0.00 Argopecten circularius impostor 8 0.00 0.00 0.00 0.00 0.00 0.00 Chacaia ovoidea 9 0.00 0.00 0.00 0.00 0.00 0.00 Chama arcana 10 0.00 0.00 0.00 0.00 0.00 0.00 Chione (Chionopsis) semiplicata 11 0.00 0.00 0.00 0.00 0.00 0.00 Chione coalingensis 12 0.00 0.00 0.00 0.00 0.00 0.00 Chione elsmerensis 13 0.00 0.00 0.00 0.00 0.00 0.00 Chione fernandoensis 14 0.00 0.00 0.00 0.00 0.00 0.00 Chione securis 15 0.00 0.00 0.00 0.00 0.00 0.00 Chlamys sp. 16 0.00 3.03 60.00 0.00 0.00 0.00 Clinocardium meekianum 17 0.00 0.00 0.00 0.00 0.00 0.00 Clinocardium sp. 18 0.00 0.00 0.00 0.00 0.00 0.00 Crassadoma gigantea 19 0.00 0.00 0.00 0.00 0.00 0.00 Crassostrea titan 20 0.00 0.00 0.00 0.00 0.00 0.00 Cuminga californica 21 0.00 0.00 0.00 0.00 0.00 0.00 Cyclocardia ventricosa 22 3.03 57.58 0.00 0.00 0.00 2.40 Dendostrea? vespertina 23 0.00 0.00 0.00 0.00 0.00 0.00 Dosiniaarnoldi 24 0.00 0.00 0.00 0.00 0.00 0.00 Dosiniajacalitosana 25 0.00 0.00 0.00 0.00 0.00 0.00 Dosniasp. 26 0.00 0.00 0.00 0.00 0.00 0.00 Felaninella harfordi 27 0.00 0.00 0.00 0.00 0.00 0.00 Florimetis dombeii 28 3.03 6.06 4.00 0.00 78.79 93.60 Glycymeris grewingki 29 0.00 0.00 0.00 0.00 0.00 0.00 Lucinomaannulatum 30 0.00 0.00 0.00 0.00 0.00 0.00 Lyropecten terminus 31 0.00 0.00 0.00 0.00 0.00 0.00 Macoma affinis plena 32 0.00 0.00 0.00 0.00 0.00 0.00 Macoma affinis plena 33Appendix C (Continued) C-21

PAGE 314

052802.06b 052802.05 052802.04 030202.06 121401.03 121401.01a Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Macoma indentataCarpenter 34 0.00 0.00 0.00 0.00 0.00 0.00 Macoma inquinata 35 0.00 0.00 0.00 0.00 3.03 1.60 Macoma (Heteromacoma) nasuta (Conrad) 36 0.00 0.00 0.00 0.00 0.00 0.00 Macoma cf.M. (Heteromacoma) nasuta (Conrad) 37 0.00 0.00 0.00 0.00 0.00 0.00 Macoma secta 38 0.00 0.00 0.00 0.00 0.00 0.00 Macoma sp. 39 0.00 0.00 0.00 0.00 0.00 0.00 Mactrid 40 0.00 0.00 0.00 0.00 0.00 0.00 Mactromeris hemphilli 41 0.00 0.00 0.00 0.00 0.00 0.00 Modiolus rectus 42 6.06 3.03 0.00 0.00 0.00 0.00 Mya arenaria 43 0.00 0.00 0.00 0.00 0.00 0.00 Mya truncata 44 0.00 0.00 0.00 0.00 0.00 0.00 Mya sp. 45 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus coalingensis 46 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus trossulus 47 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus cf.M.trossulus 48 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus sp. 49 0.00 0.00 0.00 0.00 0.00 0.00 Nuttallianuttalli 50 0.00 0.00 0.00 0.00 0.00 0.00 Oppenheimopectencoalingensis 51 0.00 0.00 0.00 0.00 0.00 0.00 Ostrea atwoodi 52 0.00 0.00 0.00 0.00 0.00 0.00 Ostrea cf.O.atwoodi 53 0.00 0.00 0.00 0.00 0.00 0.00 Pandora punctata 54 0.00 0.00 0.00 0.00 0.00 0.00 Panope estrellana 55 0.00 0.00 0.00 0.00 0.00 0.00 Panope generosa 56 0.00 0.00 0.00 0.00 0.00 0.00 Panope? sp. 57 0.00 6.06 0.00 0.00 3.03 0.00 Patinopecten lohri 58 0.00 0.00 0.00 0.00 0.00 0.00 Patinopecten sp. 59 0.00 0.00 0.00 0.00 0.00 0.00 Pectinid 60 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca cf.P.grata tarda 61 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca staleyi 62 3.03 0.00 2.00 0.00 0.00 0.00 Protothaca staminae 63 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca tennerima 64 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca sp. 65 0.00 0.00 0.00 0.00 0.00 0.00 Psephidia lordi 66Appendix C (Continued) C-22

PAGE 315

052802.06b 052802.05 052802.04 030202.06 121401.03 121401.01a Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Psephidia cf.P.lordi(Baird) 67 69.70 0.00 0.00 100.00 0.00 2.40 Pseudocardium densatum 68 0.00 0.00 0.00 0.00 3.03 0.00 Saxidomus nuttalli 69 0.00 0.00 0.00 0.00 0.00 0.00 Saxidomus nuttallilatus 70 0.00 0.00 2.00 0.00 0.00 0.00 Semelefausta 71 0.00 0.00 0.00 0.00 0.00 0.00 Semelerubripicta 72 0.00 0.00 0.00 0.00 0.00 0.00 Semelesp. 73 0.00 0.00 2.00 0.00 0.00 0.00 Solena perrini 74 3.03 0.00 0.00 0.00 0.00 0.00 Solen sicarius 75 0.00 0.00 0.00 0.00 0.00 0.00 Solen cf.S.sicarius 76 0.00 0.00 0.00 0.00 0.00 0.00 Solenid 77 0.00 0.00 0.00 0.00 3.03 0.00 Swiftopecten parmeleei etchegoini (Anderson) 78 0.00 0.00 0.00 0.00 0.00 0.00 ThraciajacalitosanaArnold 79 0.00 0.00 0.00 0.00 0.00 0.00 Tivela trigonalis 80 0.00 0.00 0.00 0.00 6.06 0.00 Trachycardium(Dallocardium) quadrigenerium 81 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardiumcf.T. (Dallocardium) quadrigenerium 82 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardiumsp. 83 0.00 0.00 12.00 0.00 0.00 0.00 Tresus nuttalli 84 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea dentata Gabb 85 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea pilbryi 86 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea sp. 87 0.00 0.00 0.00 0.00 0.00 0.00 Amnicola linginqua 88 3.03 0.00 0.00 0.00 0.00 0.00 Bittiumaspersum 89 6.06 21.21 0.00 0.00 0.00 0.00 Calliostoma coalingensis 90 0.00 0.00 0.00 0.00 0.00 0.00 Calliostoma coalingensis privum 91 0.00 0.00 0.00 0.00 0.00 0.00 Calliostoma sp. 92 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeafilosa 93 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeainornata 94 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeasp. 95 0.00 0.00 0.00 0.00 0.00 0.00 Cancellaria trintoidea 96 0.00 0.00 0.00 0.00 0.00 0.00 Cancellaria sp. 97 0.00 0.00 0.00 0.00 0.00 0.00 Clavus(Clathrodrillia) coalingensis (Arnold) 98 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula adunca 99Appendix C (Continued) C-23

PAGE 316

052802.06b 052802.05 052802.04 030202.06 121401.03 121401.01a Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula onyx 100 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula princeps 101 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula sp. 102 0.00 0.00 0.00 0.00 0.00 0.00 Fontellicella longinqua 103 0.00 0.00 0.00 0.00 0.00 0.00 Fluminicola spiralis 104 0.00 0.00 0.00 0.00 0.00 0.00 Fluminicola sp. 105 0.00 0.00 0.00 0.00 0.00 0.00 Forreria carisaensis 106 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria carisaensis mirandaensis 107 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria coalingensis 108 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria magister 109 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria magister munda 110 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria sp. 111 0.00 0.00 0.00 0.00 0.00 0.00 Gonobasis kettelmanensis 112 0.00 0.00 0.00 0.00 0.00 0.00 Litorina mariana 113 0.00 0.00 0.00 0.00 0.00 0.00 Margarita johsoni 114 0.00 0.00 0.00 0.00 0.00 0.00 Mitrellarichthofeni(Gabb) 115 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius (Demondia) californianus (Conrad) 116 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius cf. N.(Demondia) californianus (Conrad) 117 0.00 0.00 2.00 0.00 0.00 0.00 Nassarius coalingensis 118 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius iniquos 119 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius (Caesia)moranianus (Martin) 120 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius sp. 121 3.03 0.00 12.00 0.00 0.00 0.00 Neverita reclusiana 122 0.00 0.00 0.00 0.00 0.00 0.00 Nuccella etchegoinensis 123 0.00 0.00 0.00 0.00 0.00 0.00 Nuccella funkeana 124 0.00 0.00 0.00 0.00 0.00 0.00 Olivella baetica 125 0.00 0.00 0.00 0.00 0.00 0.00 Olivella biplicata 126 0.00 0.00 4.00 0.00 3.03 0.00 Polinices lewsii 127 0.00 0.00 0.00 0.00 0.00 0.00 Pleropurpura festiva(Hinds) 128 0.00 0.00 0.00 0.00 0.00 0.00 Searlesia?sp. 129 0.00 0.00 0.00 0.00 0.00 0.00 Sinumsculpulosum 130 0.00 0.00 0.00 0.00 0.00 0.00 Siphonalia kettelmanensis 131 0.00 0.00 0.00 0.00 0.00 0.00 Thais imperialis 132Appendix C (Continued) C-24

PAGE 317

0530.02.03 053002.02 053002.01a 052902.04 052802.09 052802.07 Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Acila castrensis 1 0.00 0.00 0.00 0.00 0.00 0.00 Adula gruneri 2 0.00 0.00 0.00 0.00 0.00 0.00 Aloidis gibbiformis 3 0.00 0.00 0.00 0.00 0.00 0.00 Amiantis callosa 4 0.00 0.00 0.00 0.00 0.00 0.00 Amiantis communis 5 0.00 0.00 0.00 0.00 0.00 0.00 Anadara trilineata 6 0.00 0.00 0.00 0.00 0.00 0.00 Argopecten circularius eldridgii 7 0.00 0.00 0.00 0.00 0.00 0.00 Argopecten circularius impostor 8 0.00 0.00 0.00 0.00 0.00 0.00 Chacaia ovoidea 9 0.00 0.00 0.00 0.00 0.00 0.00 Chama arcana 10 0.00 0.00 0.00 0.00 0.00 0.00 Chione (Chionopsis) semiplicata 11 0.00 0.00 0.00 0.00 0.00 0.00 Chione coalingensis 12 0.00 0.00 0.00 0.00 0.00 0.00 Chione elsmerensis 13 0.00 0.00 0.00 0.00 0.00 0.00 Chione fernandoensis 14 0.00 0.00 0.00 0.00 0.00 0.00 Chione securis 15 0.00 0.00 0.00 0.00 0.00 0.00 Chlamys sp. 16 0.00 0.00 0.00 0.00 0.00 0.00 Clinocardium meekianum 17 0.00 0.00 0.00 0.00 0.00 0.00 Clinocardium sp. 18 0.00 0.00 0.00 0.00 6.25 0.00 Crassadoma gigantea 19 0.00 0.00 0.00 0.00 0.00 0.00 Crassostrea titan 20 0.00 0.00 0.00 0.00 0.00 0.00 Cuminga californica 21 9.09 0.00 0.00 0.00 0.00 0.00 Cyclocardia ventricosa 22 0.00 0.00 0.00 14.17 56.25 0.00 Dendostrea? vespertina 23 0.00 0.00 0.00 0.00 0.00 0.00 Dosiniaarnoldi 24 0.00 0.00 0.00 0.00 0.00 0.00 Dosiniajacalitosana 25 0.00 0.00 0.00 0.00 0.00 0.00 Dosniasp. 26 0.00 0.00 0.00 0.00 0.00 0.00 Felaninella harfordi 27 0.00 0.00 0.00 0.00 0.00 0.00 Florimetis dombeii 28 0.00 31.51 0.00 0.00 0.00 3.45 Glycymeris grewingki 29 0.00 0.00 0.00 0.00 0.00 0.00 Lucinomaannulatum 30 0.00 0.00 0.00 0.00 0.00 0.00 Lyropecten terminus 31 0.00 0.00 0.00 0.00 0.00 0.00 Macoma affinis plena 32 0.00 0.00 0.00 0.00 0.00 0.00 Macoma affinis plena 33Appendix C (Continued) C-25

PAGE 318

0530.02.03 053002.02 053002.01a 052902.04 052802.09 052802.07 Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Macoma indentataCarpenter 34 0.00 0.00 0.00 0.00 0.00 0.00 Macoma inquinata 35 0.00 0.00 0.00 0.00 0.00 0.00 Macoma (Heteromacoma) nasuta (Conrad) 36 0.00 0.00 0.00 0.00 0.00 0.00 Macoma cf.M. (Heteromacoma) nasuta (Conrad) 37 0.00 0.00 0.00 0.00 0.00 0.00 Macoma secta 38 0.00 0.00 0.00 0.00 0.00 0.00 Macoma sp. 39 0.00 0.00 0.00 0.00 0.00 0.00 Mactrid 40 0.00 0.00 0.00 0.00 0.00 0.00 Mactromeris hemphilli 41 0.00 0.00 0.00 0.00 0.00 0.00 Modiolus rectus 42 90.91 8.22 65.52 0.00 6.25 3.45 Mya arenaria 43 0.00 0.00 0.00 0.00 0.00 0.00 Mya truncata 44 0.00 0.00 0.00 0.00 0.00 0.00 Mya sp. 45 0.00 1.37 10.34 0.00 0.00 0.00 Mytilus coalingensis 46 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus trossulus 47 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus cf.M.trossulus 48 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus sp. 49 0.00 0.00 0.00 0.00 0.00 0.00 Nuttallianuttalli 50 0.00 0.00 0.00 85.83 0.00 0.00 Oppenheimopectencoalingensis 51 0.00 0.00 0.00 0.00 0.00 0.00 Ostrea atwoodi 52 0.00 0.00 0.00 0.00 0.00 0.00 Ostrea cf.O.atwoodi 53 0.00 0.00 0.00 0.00 0.00 0.00 Pandora punctata 54 0.00 0.00 0.00 0.00 0.00 0.00 Panope estrellana 55 0.00 0.00 0.00 0.00 0.00 0.00 Panope generosa 56 0.00 0.00 0.00 0.00 0.00 0.00 Panope? sp. 57 0.00 0.00 0.00 0.00 0.00 0.00 Patinopecten lohri 58 0.00 0.00 0.00 0.00 0.00 0.00 Patinopecten sp. 59 0.00 0.00 0.00 0.00 0.00 0.00 Pectinid 60 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca cf.P.grata tarda 61 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca staleyi 62 0.00 2.74 3.45 0.00 0.00 0.00 Protothaca staminae 63 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca tennerima 64 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca sp. 65 0.00 0.00 0.00 0.00 0.00 0.00 Psephidia lordi 66Appendix C (Continued) C-26

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0530.02.03 053002.02 053002.01a 052902.04 052802.09 052802.07 Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Psephidia cf.P.lordi(Baird) 67 0.00 23.29 0.00 0.00 31.25 82.76 Pseudocardium densatum 68 0.00 2.74 0.00 0.00 0.00 0.00 Saxidomus nuttalli 69 0.00 0.00 0.00 0.00 0.00 0.00 Saxidomus nuttallilatus 70 0.00 0.00 0.00 0.00 0.00 0.00 Semelefausta 71 0.00 0.00 3.45 0.00 0.00 0.00 Semelerubripicta 72 0.00 0.00 0.00 0.00 0.00 0.00 Semelesp. 73 0.00 0.00 0.00 0.00 0.00 0.00 Solena perrini 74 0.00 1.37 17.24 0.00 0.00 0.00 Solen sicarius 75 0.00 0.00 0.00 0.00 0.00 0.00 Solen cf.S.sicarius 76 0.00 0.00 0.00 0.00 0.00 0.00 Solenid 77 0.00 0.00 0.00 0.00 0.00 0.00 Swiftopecten parmeleei etchegoini (Anderson) 78 0.00 0.00 0.00 0.00 0.00 0.00 ThraciajacalitosanaArnold 79 0.00 0.00 0.00 0.00 0.00 0.00 Tivela trigonalis 80 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardium(Dallocardium) quadrigenerium 81 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardiumcf.T. (Dallocardium) quadrigenerium 82 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardiumsp. 83 0.00 0.00 0.00 0.00 0.00 0.00 Tresus nuttalli 84 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea dentata Gabb 85 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea pilbryi 86 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea sp. 87 0.00 0.00 0.00 0.00 0.00 0.00 Amnicola linginqua 88 0.00 6.85 0.00 0.00 0.00 10.34 Bittiumaspersum 89 0.00 1.37 0.00 0.00 0.00 0.00 Calliostoma coalingensis 90 0.00 0.00 0.00 0.00 0.00 0.00 Calliostoma coalingensis privum 91 0.00 0.00 0.00 0.00 0.00 0.00 Calliostoma sp. 92 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeafilosa 93 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeainornata 94 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeasp. 95 0.00 0.00 0.00 0.00 0.00 0.00 Cancellaria trintoidea 96 0.00 0.00 0.00 0.00 0.00 0.00 Cancellaria sp. 97 0.00 0.00 0.00 0.00 0.00 0.00 Clavus(Clathrodrillia) coalingensis (Arnold) 98 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula adunca 99Appendix C (Continued) C-27

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0530.02.03 053002.02 053002.01a 052902.04 052802.09 052802.07 Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula onyx 100 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula princeps 101 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula sp. 102 0.00 0.00 0.00 0.00 0.00 0.00 Fontellicella longinqua 103 0.00 0.00 0.00 0.00 0.00 0.00 Fluminicola spiralis 104 0.00 0.00 0.00 0.00 0.00 0.00 Fluminicola sp. 105 0.00 0.00 0.00 0.00 0.00 0.00 Forreria carisaensis 106 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria carisaensis mirandaensis 107 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria coalingensis 108 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria magister 109 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria magister munda 110 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria sp. 111 0.00 0.00 0.00 0.00 0.00 0.00 Gonobasis kettelmanensis 112 0.00 0.00 0.00 0.00 0.00 0.00 Litorina mariana 113 0.00 0.00 0.00 0.00 0.00 0.00 Margarita johsoni 114 0.00 0.00 0.00 0.00 0.00 0.00 Mitrellarichthofeni(Gabb) 115 0.00 5.48 0.00 0.00 0.00 0.00 Nassarius (Demondia) californianus (Conrad) 116 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius cf. N.(Demondia) californianus (Conrad) 117 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius coalingensis 118 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius iniquos 119 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius (Caesia)moranianus (Martin) 120 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius sp. 121 0.00 0.00 0.00 0.00 0.00 0.00 Neverita reclusiana 122 0.00 0.00 0.00 0.00 0.00 0.00 Nuccella etchegoinensis 123 0.00 0.00 0.00 0.00 0.00 0.00 Nuccella funkeana 124 0.00 0.00 0.00 0.00 0.00 0.00 Olivella baetica 125 0.00 15.07 0.00 0.00 0.00 0.00 Olivella biplicata 126 0.00 0.00 0.00 0.00 0.00 0.00 Polinices lewsii 127 0.00 0.00 0.00 0.00 0.00 0.00 Pleropurpura festiva(Hinds) 128 0.00 0.00 0.00 0.00 0.00 0.00 Searlesia?sp. 129 0.00 0.00 0.00 0.00 0.00 0.00 Sinumsculpulosum 130 0.00 0.00 0.00 0.00 0.00 0.00 Siphonalia kettelmanensis 131 0.00 0.00 0.00 0.00 0.00 0.00 Thais imperialis 132Appendix C (Continued) C-28

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110702.08 110702.07 110702.06 110702.03 110702.01 053102.01 Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Acila castrensis 1 0.00 0.00 0.00 0.00 0.00 0.48 Adula gruneri 2 0.00 0.00 0.00 0.00 0.93 0.00 Aloidis gibbiformis 3 0.00 0.00 0.00 4.19 0.00 0.00 Amiantis callosa 4 0.00 0.00 0.00 0.00 7.48 0.00 Amiantis communis 5 0.83 0.00 6.52 0.00 0.00 0.00 Anadara trilineata 6 0.00 0.00 0.00 0.00 0.00 0.00 Argopecten circularius eldridgii 7 0.00 0.00 0.00 0.00 0.00 0.00 Argopecten circularius impostor 8 0.00 0.00 0.00 0.00 0.00 0.00 Chacaia ovoidea 9 0.00 0.00 0.00 0.00 0.00 0.00 Chama arcana 10 0.00 0.00 0.00 1.20 0.00 1.44 Chione (Chionopsis) semiplicata 11 0.00 0.00 0.00 0.60 0.00 0.00 Chione coalingensis 12 0.00 0.00 0.00 0.00 0.00 0.00 Chione elsmerensis 13 0.00 0.00 0.00 1.20 2.80 0.00 Chione fernandoensis 14 0.00 0.00 0.00 0.00 3.74 0.00 Chione securis 15 0.00 0.00 0.00 0.00 0.00 0.00 Chlamys sp. 16 0.00 8.00 0.00 0.00 0.00 0.00 Clinocardium meekianum 17 0.00 0.00 0.00 0.00 0.00 0.00 Clinocardium sp. 18 0.00 0.00 0.00 0.00 0.00 0.00 Crassadoma gigantea 19 0.00 0.00 0.00 0.00 0.00 0.00 Crassostrea titan 20 0.00 0.00 0.00 0.00 0.00 0.48 Cuminga californica 21 0.00 0.00 0.00 0.00 0.00 0.00 Cyclocardia ventricosa 22 0.00 0.00 0.00 0.00 0.00 0.00 Dendostrea? vespertina 23 0.00 0.00 0.00 0.00 11.21 0.00 Dosiniaarnoldi 24 0.00 0.00 0.00 5.99 0.00 0.00 Dosiniajacalitosana 25 0.00 0.00 0.00 0.00 0.00 0.00 Dosniasp. 26 0.00 0.00 0.00 0.00 0.00 0.00 Felaninella harfordi 27 0.00 4.00 0.00 0.00 0.00 0.00 Florimetis dombeii 28 34.17 16.00 2.17 1.80 0.00 0.00 Glycymeris grewingki 29 0.00 0.00 0.00 0.00 0.00 0.00 Lucinomaannulatum 30 0.00 0.00 0.00 0.00 0.00 0.00 Lyropecten terminus 31 0.00 0.00 0.00 0.00 0.00 0.00 Macoma affinis plena 32 0.00 0.00 0.00 0.00 0.00 0.00 Macoma affinis plena 33Appendix C (Continued) C-29

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110702.08 110702.07 110702.06 110702.03 110702.01 053102.01 Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Macoma indentataCarpenter 34 0.00 0.00 0.00 0.00 0.00 0.00 Macoma inquinata 35 0.00 0.00 0.00 17.96 21.50 0.00 Macoma (Heteromacoma) nasuta (Conrad) 36 0.00 0.00 0.00 0.00 0.00 9.09 Macoma cf.M. (Heteromacoma) nasuta (Conrad) 37 0.00 0.00 0.00 0.00 0.00 0.00 Macoma secta 38 0.00 0.00 0.00 0.00 0.00 0.00 Macoma sp. 39 0.00 0.00 0.00 0.00 0.00 0.00 Mactrid 40 0.00 0.00 0.00 0.00 0.00 0.00 Mactromeris hemphilli 41 0.00 0.00 0.00 0.00 0.00 0.00 Modiolus rectus 42 3.33 24.00 10.87 8.38 0.00 0.00 Mya arenaria 43 0.00 0.00 0.00 0.00 0.00 0.00 Mya truncata 44 0.00 0.00 0.00 0.00 0.00 0.00 Mya sp. 45 1.67 20.00 0.00 0.60 0.00 0.00 Mytilus coalingensis 46 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus trossulus 47 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus cf.M.trossulus 48 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus sp. 49 0.00 4.00 0.00 0.00 0.00 0.00 Nuttallianuttalli 50 0.00 0.00 0.00 0.00 0.00 0.00 Oppenheimopectencoalingensis 51 0.00 0.00 0.00 0.00 0.00 0.00 Ostrea atwoodi 52 0.00 0.00 0.00 0.00 0.00 0.00 Ostrea cf.O.atwoodi 53 0.00 0.00 0.00 0.00 0.00 0.00 Pandora punctata 54 0.00 0.00 0.00 0.00 0.93 0.00 Panope estrellana 55 0.00 0.00 0.00 0.00 0.00 0.00 Panope generosa 56 0.00 0.00 0.00 0.00 0.00 0.00 Panope? sp. 57 0.00 0.00 0.00 0.00 0.00 0.00 Patinopecten lohri 58 0.00 0.00 0.00 0.00 0.00 0.00 Patinopecten sp. 59 0.00 0.00 0.00 0.00 0.00 0.00 Pectinid 60 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca cf.P.grata tarda 61 27.50 0.00 0.00 0.00 0.00 0.00 Protothaca staleyi 62 0.00 4.00 15.22 0.00 0.00 0.48 Protothaca staminae 63 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca tennerima 64 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca sp. 65 0.00 0.00 0.00 0.00 0.00 0.00 Psephidia lordi 66Appendix C (Continued) C-30

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110702.08 110702.07 110702.06 110702.03 110702.01 053102.01 Species no. 0.00 0.00 0.00 0.00 0.00 2.87 Psephidia cf.P.lordi(Baird) 67 8.33 0.00 50.00 1.20 0.00 24.88 Pseudocardium densatum 68 0.00 0.00 0.00 0.00 0.00 0.00 Saxidomus nuttalli 69 0.00 0.00 0.00 0.00 0.00 0.00 Saxidomus nuttallilatus 70 0.00 0.00 0.00 0.00 0.00 0.00 Semelefausta 71 0.00 4.00 0.00 0.00 0.00 0.00 Semelerubripicta 72 0.00 0.00 0.00 0.00 0.00 0.00 Semelesp. 73 0.00 0.00 0.00 0.60 0.00 0.00 Solena perrini 74 0.00 0.00 0.00 0.00 0.00 0.48 Solen sicarius 75 0.00 0.00 0.00 0.00 0.00 0.00 Solen cf.S.sicarius 76 0.00 0.00 0.00 0.00 0.00 0.00 Solenid 77 0.00 0.00 0.00 0.00 0.00 0.00 Swiftopecten parmeleei etchegoini (Anderson) 78 0.00 0.00 0.00 0.00 0.00 2.39 ThraciajacalitosanaArnold 79 0.00 0.00 0.00 2.40 0.00 0.00 Tivela trigonalis 80 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardium(Dallocardium) quadrigenerium 81 0.00 0.00 0.00 0.00 0.00 0.48 Trachycardiumcf.T. (Dallocardium) quadrigenerium 82 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardiumsp. 83 0.00 0.00 0.00 4.79 0.00 0.00 Tresus nuttalli 84 0.00 0.00 0.00 0.00 0.00 0.48 Zirfaea dentata Gabb 85 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea pilbryi 86 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea sp. 87 0.00 0.00 0.00 0.00 0.00 0.00 Amnicola linginqua 88 1.67 0.00 0.00 0.00 0.00 0.00 Bittiumaspersum 89 0.00 0.00 0.00 5.39 0.00 0.00 Calliostoma coalingensis 90 5.00 0.00 0.00 0.00 0.00 0.00 Calliostoma coalingensis privum 91 0.00 0.00 0.00 0.00 0.00 0.00 Calliostoma sp. 92 0.00 0.00 4.35 0.00 0.00 0.00 Calyptraeafilosa 93 0.83 4.00 0.00 0.00 0.00 0.00 Calyptraeainornata 94 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeasp. 95 5.00 0.00 0.00 0.00 4.67 0.00 Cancellaria trintoidea 96 0.00 0.00 0.00 0.00 0.00 0.00 Cancellaria sp. 97 0.00 0.00 0.00 0.00 0.00 0.00 Clavus(Clathrodrillia) coalingensis (Arnold) 98 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula adunca 99Appendix C (Continued) C-31

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110702.08 110702.07 110702.06 110702.03 110702.01 053102.01 Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula onyx 100 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula princeps 101 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula sp. 102 0.00 0.00 8.70 0.00 0.00 0.00 Fontellicella longinqua 103 1.67 0.00 0.00 0.00 0.00 0.00 Fluminicola spiralis 104 0.00 0.00 0.00 0.00 0.00 0.00 Fluminicola sp. 105 0.00 0.00 0.00 0.00 0.00 0.00 Forreria carisaensis 106 0.00 0.00 0.00 0.00 2.80 0.00 Forrerria carisaensis mirandaensis 107 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria coalingensis 108 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria magister 109 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria magister munda 110 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria sp. 111 0.00 0.00 0.00 0.00 0.00 0.00 Gonobasis kettelmanensis 112 0.00 0.00 0.00 0.00 0.00 0.48 Litorina mariana 113 0.00 0.00 0.00 0.00 0.00 0.00 Margarita johsoni 114 0.00 0.00 0.00 0.00 0.00 0.00 Mitrellarichthofeni(Gabb) 115 1.67 0.00 2.17 0.00 0.00 0.00 Nassarius (Demondia) californianus (Conrad) 116 0.00 0.00 0.00 0.00 0.00 2.87 Nassarius cf. N.(Demondia) californianus (Conrad) 117 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius coalingensis 118 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius iniquos 119 0.00 4.00 0.00 0.00 0.00 0.00 Nassarius (Caesia)moranianus (Martin) 120 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius sp. 121 3.33 8.00 0.00 2.99 1.87 0.00 Neverita reclusiana 122 0.00 0.00 0.00 0.00 0.00 0.00 Nuccella etchegoinensis 123 0.00 0.00 0.00 0.00 0.00 0.00 Nuccella funkeana 124 0.00 0.00 0.00 0.00 0.00 0.00 Olivella baetica 125 0.00 0.00 0.00 0.00 0.00 0.00 Olivella biplicata 126 0.00 0.00 0.00 7.19 0.00 0.00 Polinices lewsii 127 0.00 0.00 0.00 0.00 0.00 0.00 Pleropurpura festiva(Hinds) 128 0.00 0.00 0.00 0.00 0.00 0.00 Searlesia?sp. 129 0.00 0.00 0.00 0.00 10.28 0.00 Sinumsculpulosum 130 0.00 0.00 0.00 0.60 0.00 0.00 Siphonalia kettelmanensis 131 0.00 0.00 0.00 1.20 0.00 0.00 Thais imperialis 132Appendix C (Continued) C-32

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052704.04 052704.02 110802.05 110802.04 110702.10 110702.09 Species no. 0.00 0.00 0.00 0.00 12.22 0.00 Acila castrensis 1 0.00 0.00 0.00 0.00 0.00 0.00 Adula gruneri 2 0.00 0.00 0.00 0.00 0.00 0.00 Aloidis gibbiformis 3 0.00 0.00 0.00 0.00 0.00 0.00 Amiantis callosa 4 0.00 0.00 0.00 0.00 0.00 0.00 Amiantis communis 5 0.00 0.00 0.00 0.00 28.89 5.77 Anadara trilineata 6 0.00 0.00 0.00 0.00 0.00 0.00 Argopecten circularius eldridgii 7 0.00 0.00 0.00 0.00 0.00 0.00 Argopecten circularius impostor 8 0.00 0.00 0.00 0.00 0.00 1.92 Chacaia ovoidea 9 0.00 0.00 0.00 0.00 0.00 15.38 Chama arcana 10 0.00 0.00 0.00 0.00 0.00 0.00 Chione (Chionopsis) semiplicata 11 0.00 0.00 0.00 0.00 0.00 0.00 Chione coalingensis 12 0.00 0.00 92.59 14.29 0.00 0.00 Chione elsmerensis 13 0.00 0.00 0.00 0.00 0.00 0.00 Chione fernandoensis 14 0.00 0.00 0.00 0.00 0.00 0.00 Chione securis 15 0.00 0.00 0.00 0.00 0.00 0.00 Chlamys sp. 16 6.67 0.00 0.00 17.14 0.00 0.00 Clinocardium meekianum 17 0.00 0.00 0.00 0.00 0.00 0.00 Clinocardium sp. 18 0.00 0.00 0.00 0.00 0.00 0.00 Crassadoma gigantea 19 0.00 0.00 0.00 0.00 0.00 0.00 Crassostrea titan 20 0.00 0.00 0.00 0.00 0.00 0.00 Cuminga californica 21 0.00 0.00 0.00 0.00 0.00 0.00 Cyclocardia ventricosa 22 0.00 0.00 0.00 0.00 0.00 1.92 Dendostrea? vespertina 23 0.00 0.00 0.00 0.00 0.00 0.00 Dosiniaarnoldi 24 0.00 0.00 0.00 0.00 0.00 0.00 Dosiniajacalitosana 25 0.00 0.00 0.00 0.00 0.00 0.00 Dosniasp. 26 0.00 0.00 0.00 0.00 0.00 0.00 Felaninella harfordi 27 0.00 0.00 0.00 0.00 0.00 0.00 Florimetis dombeii 28 26.67 0.00 0.00 0.00 0.00 0.00 Glycymeris grewingki 29 0.00 0.00 0.00 0.00 0.00 0.00 Lucinomaannulatum 30 0.00 100.00 0.00 0.00 0.00 0.00 Lyropecten terminus 31 0.00 0.00 0.00 0.00 0.00 1.92 Macoma affinis plena 32 0.00 0.00 0.00 0.00 0.00 0.00 Macoma affinis plena 33Appendix C (Continued) C-33

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052704.04 052704.02 110802.05 110802.04 110702.10 110702.09 Species no. 0.00 0.00 0.00 2.86 0.00 0.00 Macoma indentataCarpenter 34 0.00 0.00 0.00 0.00 0.00 0.00 Macoma inquinata 35 0.00 0.00 0.00 0.00 0.00 0.00 Macoma (Heteromacoma) nasuta (Conrad) 36 0.00 0.00 0.00 0.00 0.00 0.00 Macoma cf.M. (Heteromacoma) nasuta (Conrad) 37 0.00 0.00 0.00 0.00 0.00 0.00 Macoma secta 38 0.00 0.00 0.00 0.00 0.00 0.00 Macoma sp. 39 0.00 0.00 0.00 0.00 0.00 0.00 Mactrid 40 0.00 0.00 0.00 0.00 0.00 0.00 Mactromeris hemphilli 41 0.00 0.00 0.00 0.00 0.00 0.00 Modiolus rectus 42 0.00 0.00 0.00 0.00 0.00 0.00 Mya arenaria 43 0.00 0.00 0.00 0.00 0.00 0.00 Mya truncata 44 0.00 0.00 0.00 0.00 0.00 0.00 Mya sp. 45 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus coalingensis 46 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus trossulus 47 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus cf.M.trossulus 48 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus sp. 49 0.00 0.00 0.00 0.00 0.00 0.00 Nuttallianuttalli 50 0.00 0.00 0.00 0.00 0.00 30.77 Oppenheimopectencoalingensis 51 46.67 0.00 0.00 0.00 0.00 0.00 Ostrea atwoodi 52 0.00 0.00 0.00 0.00 0.00 0.00 Ostrea cf.O.atwoodi 53 0.00 0.00 0.00 0.00 0.00 0.00 Pandora punctata 54 0.00 0.00 0.00 0.00 0.00 0.00 Panope estrellana 55 0.00 0.00 0.00 0.00 0.00 3.85 Panope generosa 56 0.00 0.00 0.00 0.00 0.00 0.00 Panope? sp. 57 0.00 0.00 0.00 0.00 0.00 0.00 Patinopecten lohri 58 0.00 0.00 7.41 0.00 0.00 0.00 Patinopecten sp. 59 0.00 0.00 0.00 0.00 0.00 0.00 Pectinid 60 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca cf.P.grata tarda 61 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca staleyi 62 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca staminae 63 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca tennerima 64 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca sp. 65 0.00 0.00 0.00 0.00 0.00 0.00 Psephidia lordi 66Appendix C (Continued) C-34

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052704.04 052704.02 110802.05 110802.04 110702.10 110702.09 Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Psephidia cf.P.lordi(Baird) 67 0.00 0.00 0.00 0.00 0.00 0.00 Pseudocardium densatum 68 0.00 0.00 0.00 0.00 0.00 3.85 Saxidomus nuttalli 69 0.00 0.00 0.00 20.00 0.00 0.00 Saxidomus nuttallilatus 70 0.00 0.00 0.00 0.00 0.00 0.00 Semelefausta 71 0.00 0.00 0.00 0.00 0.00 0.00 Semelerubripicta 72 0.00 0.00 0.00 0.00 0.00 0.00 Semelesp. 73 0.00 0.00 0.00 0.00 0.00 0.00 Solena perrini 74 0.00 0.00 0.00 0.00 0.00 0.00 Solen sicarius 75 0.00 0.00 0.00 0.00 1.11 0.00 Solen cf.S.sicarius 76 0.00 0.00 0.00 0.00 0.00 0.00 Solenid 77 0.00 0.00 0.00 0.00 0.00 0.00 Swiftopecten parmeleei etchegoini (Anderson) 78 0.00 0.00 0.00 0.00 0.00 0.00 ThraciajacalitosanaArnold 79 0.00 0.00 0.00 0.00 0.00 0.00 Tivela trigonalis 80 0.00 0.00 0.00 0.00 0.00 1.92 Trachycardium(Dallocardium) quadrigenerium 81 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardiumcf.T. (Dallocardium) quadrigenerium 82 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardiumsp. 83 0.00 0.00 0.00 0.00 0.00 0.00 Tresus nuttalli 84 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea dentata Gabb 85 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea pilbryi 86 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea sp. 87 0.00 0.00 0.00 0.00 0.00 0.00 Amnicola linginqua 88 0.00 0.00 0.00 0.00 0.00 0.00 Bittiumaspersum 89 0.00 0.00 0.00 0.00 0.00 0.00 Calliostoma coalingensis 90 0.00 0.00 0.00 0.00 0.00 0.00 Calliostoma coalingensis privum 91 0.00 0.00 0.00 0.00 0.00 0.00 Calliostoma sp. 92 0.00 0.00 0.00 0.00 56.67 0.00 Calyptraeafilosa 93 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeainornata 94 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeasp. 95 0.00 0.00 0.00 0.00 0.00 0.00 Cancellaria trintoidea 96 0.00 0.00 0.00 0.00 0.00 0.00 Cancellaria sp. 97 0.00 0.00 0.00 0.00 0.00 0.00 Clavus(Clathrodrillia) coalingensis (Arnold) 98 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula adunca 99Appendix C (Continued) C-35

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052704.04 052704.02 110802.05 110802.04 110702.10 110702.09 Species no. 0.00 0.00 0.00 0.00 1.11 0.00 Crepidula onyx 100 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula princeps 101 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula sp. 102 0.00 0.00 0.00 0.00 0.00 0.00 Fontellicella longinqua 103 0.00 0.00 0.00 0.00 0.00 0.00 Fluminicola spiralis 104 0.00 0.00 0.00 0.00 0.00 0.00 Fluminicola sp. 105 0.00 0.00 0.00 28.57 0.00 0.00 Forreria carisaensis 106 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria carisaensis mirandaensis 107 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria coalingensis 108 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria magister 109 0.00 0.00 0.00 5.71 0.00 0.00 Forrerria magister munda 110 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria sp. 111 0.00 0.00 0.00 0.00 0.00 1.92 Gonobasis kettelmanensis 112 0.00 0.00 0.00 0.00 0.00 0.00 Litorina mariana 113 0.00 0.00 0.00 0.00 0.00 0.00 Margarita johsoni 114 0.00 0.00 0.00 0.00 0.00 0.00 Mitrellarichthofeni(Gabb) 115 6.67 0.00 0.00 0.00 0.00 0.00 Nassarius (Demondia) californianus (Conrad) 116 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius cf. N.(Demondia) californianus (Conrad) 117 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius coalingensis 118 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius iniquos 119 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius (Caesia)moranianus (Martin) 120 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius sp. 121 0.00 0.00 0.00 11.43 0.00 28.85 Neverita reclusiana 122 13.33 0.00 0.00 0.00 0.00 0.00 Nuccella etchegoinensis 123 0.00 0.00 0.00 0.00 0.00 0.00 Nuccella funkeana 124 0.00 0.00 0.00 0.00 0.00 0.00 Olivella baetica 125 0.00 0.00 0.00 0.00 0.00 0.00 Olivella biplicata 126 0.00 0.00 0.00 0.00 0.00 0.00 Polinices lewsii 127 0.00 0.00 0.00 0.00 0.00 1.92 Pleropurpura festiva(Hinds) 128 0.00 0.00 0.00 0.00 0.00 0.00 Searlesia?sp. 129 0.00 0.00 0.00 0.00 0.00 0.00 Sinumsculpulosum 130 0.00 0.00 0.00 0.00 0.00 0.00 Siphonalia kettelmanensis 131 0.00 0.00 0.00 0.00 0.00 0.00 Thais imperialis 132Appendix C (Continued) C-36

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052704.08 052704.07c 052704.07b 052704.07a 052704.06 052704.05 Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Acila castrensis 1 0.00 0.00 0.00 10.00 0.00 0.00 Adula gruneri 2 0.00 0.00 0.00 0.00 0.00 0.00 Aloidis gibbiformis 3 0.00 0.00 0.00 0.00 0.00 0.00 Amiantis callosa 4 0.00 0.00 0.00 0.00 0.00 0.00 Amiantis communis 5 0.00 3.57 11.76 0.00 20.00 0.00 Anadara trilineata 6 0.00 0.00 0.00 0.00 0.00 0.00 Argopecten circularius eldridgii 7 0.00 0.00 0.00 0.00 0.00 0.00 Argopecten circularius impostor 8 0.00 0.00 0.00 0.00 0.00 0.00 Chacaia ovoidea 9 0.00 0.00 0.00 0.00 0.00 0.00 Chama arcana 10 0.00 0.00 0.00 0.00 0.00 0.00 Chione (Chionopsis) semiplicata 11 0.00 0.00 0.00 0.00 0.00 0.00 Chione coalingensis 12 0.00 0.00 0.00 0.00 0.00 0.00 Chione elsmerensis 13 0.00 0.00 0.00 0.00 0.00 0.00 Chione fernandoensis 14 0.00 0.00 0.00 0.00 0.00 0.00 Chione securis 15 0.00 0.00 0.00 0.00 0.00 0.00 Chlamys sp. 16 5.13 17.86 0.00 40.00 0.00 0.00 Clinocardium meekianum 17 0.00 0.00 0.00 0.00 0.00 0.00 Clinocardium sp. 18 0.00 0.00 0.00 0.00 0.00 0.00 Crassadoma gigantea 19 0.00 0.00 0.00 0.00 0.00 0.00 Crassostrea titan 20 0.00 0.00 0.00 0.00 0.00 0.00 Cuminga californica 21 0.00 0.00 0.00 0.00 0.00 0.00 Cyclocardia ventricosa 22 0.00 0.00 0.00 0.00 0.00 0.00 Dendostrea? vespertina 23 0.00 0.00 0.00 0.00 0.00 0.00 Dosiniaarnoldi 24 0.00 0.00 0.00 0.00 0.00 0.00 Dosiniajacalitosana 25 0.00 0.00 0.00 0.00 0.00 0.00 Dosniasp. 26 44.87 0.00 0.00 0.00 0.00 0.00 Felaninella harfordi 27 0.00 0.00 0.00 0.00 0.00 0.00 Florimetis dombeii 28 0.00 17.86 0.00 0.00 20.00 76.19 Glycymeris grewingki 29 0.00 0.00 0.00 0.00 0.00 0.00 Lucinomaannulatum 30 0.00 0.00 0.00 0.00 0.00 0.00 Lyropecten terminus 31 0.00 0.00 0.00 0.00 0.00 0.00 Macoma affinis plena 32 0.00 0.00 0.00 0.00 0.00 0.00 Macoma affinis plena 33Appendix C (Continued) C-37

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052704.08 052704.07c 052704.07b 052704.07a 052704.06 052704.05 Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Macoma indentataCarpenter 34 0.00 0.00 0.00 0.00 0.00 0.00 Macoma inquinata 35 0.00 0.00 0.00 0.00 0.00 0.00 Macoma (Heteromacoma) nasuta (Conrad) 36 0.00 0.00 0.00 0.00 0.00 0.00 Macoma cf.M. (Heteromacoma) nasuta (Conrad) 37 0.00 0.00 0.00 0.00 0.00 0.00 Macoma secta 38 0.00 0.00 0.00 0.00 0.00 0.00 Macoma sp. 39 0.00 0.00 0.00 0.00 0.00 0.00 Mactrid 40 0.00 0.00 0.00 0.00 0.00 0.00 Mactromeris hemphilli 41 0.00 0.00 0.00 0.00 0.00 0.00 Modiolus rectus 42 0.00 0.00 23.53 10.00 10.00 0.00 Mya arenaria 43 0.00 0.00 0.00 0.00 0.00 0.00 Mya truncata 44 0.00 0.00 0.00 0.00 0.00 0.00 Mya sp. 45 0.00 3.57 0.00 0.00 0.00 0.00 Mytilus coalingensis 46 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus trossulus 47 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus cf.M.trossulus 48 0.00 0.00 0.00 0.00 0.00 0.00 Mytilus sp. 49 0.00 0.00 0.00 0.00 0.00 0.00 Nuttallianuttalli 50 0.00 0.00 0.00 0.00 0.00 0.00 Oppenheimopectencoalingensis 51 0.00 0.00 0.00 0.00 0.00 23.81 Ostrea atwoodi 52 0.00 0.00 0.00 0.00 10.00 0.00 Ostrea cf.O.atwoodi 53 0.00 0.00 0.00 0.00 0.00 0.00 Pandora punctata 54 0.00 0.00 0.00 0.00 0.00 0.00 Panope estrellana 55 0.00 0.00 0.00 0.00 0.00 0.00 Panope generosa 56 0.00 0.00 0.00 0.00 0.00 0.00 Panope? sp. 57 0.00 0.00 0.00 0.00 0.00 0.00 Patinopecten lohri 58 0.00 0.00 0.00 0.00 0.00 0.00 Patinopecten sp. 59 0.00 0.00 0.00 0.00 0.00 0.00 Pectinid 60 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca cf.P.grata tarda 61 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca staleyi 62 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca staminae 63 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca tennerima 64 0.00 0.00 0.00 0.00 0.00 0.00 Protothaca sp. 65 0.00 0.00 0.00 0.00 0.00 0.00 Psephidia lordi 66Appendix C (Continued) C-38

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052704.08 052704.07c 052704.07b 052704.07a 052704.06 052704.05 Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Psephidia cf.P.lordi(Baird) 67 0.00 3.57 41.18 10.00 20.00 0.00 Pseudocardium densatum 68 6.41 0.00 0.00 20.00 0.00 0.00 Saxidomus nuttalli 69 0.00 0.00 0.00 0.00 0.00 0.00 Saxidomus nuttallilatus 70 0.00 0.00 0.00 0.00 0.00 0.00 Semelefausta 71 0.00 0.00 0.00 0.00 0.00 0.00 Semelerubripicta 72 0.00 0.00 0.00 0.00 0.00 0.00 Semelesp. 73 0.00 0.00 0.00 0.00 0.00 0.00 Solena perrini 74 3.85 25.00 5.88 0.00 0.00 0.00 Solen sicarius 75 0.00 0.00 0.00 0.00 0.00 0.00 Solen cf.S.sicarius 76 0.00 0.00 0.00 0.00 0.00 0.00 Solenid 77 0.00 0.00 0.00 0.00 0.00 0.00 Swiftopecten parmeleei etchegoini (Anderson) 78 0.00 0.00 0.00 0.00 0.00 0.00 ThraciajacalitosanaArnold 79 0.00 0.00 0.00 0.00 0.00 0.00 Tivela trigonalis 80 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardium(Dallocardium) quadrigenerium 81 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardiumcf.T. (Dallocardium) quadrigenerium 82 0.00 0.00 0.00 0.00 0.00 0.00 Trachycardiumsp. 83 0.00 0.00 0.00 0.00 0.00 0.00 Tresus nuttalli 84 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea dentata Gabb 85 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea pilbryi 86 0.00 0.00 0.00 0.00 0.00 0.00 Zirfaea sp. 87 0.00 0.00 0.00 0.00 0.00 0.00 Amnicola linginqua 88 0.00 0.00 0.00 0.00 0.00 0.00 Bittiumaspersum 89 0.00 14.29 5.88 0.00 0.00 0.00 Calliostoma coalingensis 90 0.00 0.00 0.00 0.00 0.00 0.00 Calliostoma coalingensis privum 91 0.00 0.00 0.00 0.00 0.00 0.00 Calliostoma sp. 92 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeafilosa 93 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeainornata 94 0.00 0.00 0.00 0.00 0.00 0.00 Calyptraeasp. 95 0.00 0.00 0.00 0.00 0.00 0.00 Cancellaria trintoidea 96 0.00 0.00 0.00 0.00 0.00 0.00 Cancellaria sp. 97 0.00 0.00 0.00 0.00 0.00 0.00 Clavus(Clathrodrillia) coalingensis (Arnold) 98 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula adunca 99Appendix C (Continued) C-39

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052704.08 052704.07c 052704.07b 052704.07a 052704.06 052704.05 Species no. 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula onyx 100 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula princeps 101 0.00 0.00 0.00 0.00 0.00 0.00 Crepidula sp. 102 0.00 0.00 0.00 0.00 0.00 0.00 Fontellicella longinqua 103 0.00 0.00 0.00 0.00 0.00 0.00 Fluminicola spiralis 104 0.00 0.00 0.00 0.00 0.00 0.00 Fluminicola sp. 105 0.00 0.00 0.00 0.00 0.00 0.00 Forreria carisaensis 106 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria carisaensis mirandaensis 107 0.00 0.00 0.00 0.00 10.00 0.00 Forrerria coalingensis 108 2.56 0.00 0.00 0.00 0.00 0.00 Forrerria magister 109 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria magister munda 110 0.00 0.00 0.00 0.00 0.00 0.00 Forrerria sp. 111 0.00 0.00 0.00 0.00 0.00 0.00 Gonobasis kettelmanensis 112 0.00 10.71 0.00 0.00 0.00 0.00 Litorina mariana 113 30.77 0.00 0.00 0.00 0.00 0.00 Margarita johsoni 114 0.00 0.00 0.00 0.00 0.00 0.00 Mitrellarichthofeni(Gabb) 115 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius (Demondia) californianus (Conrad) 116 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius cf. N.(Demondia) californianus (Conrad) 117 2.56 0.00 5.88 0.00 0.00 0.00 Nassarius coalingensis 118 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius iniquos 119 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius (Caesia)moranianus (Martin) 120 0.00 0.00 0.00 0.00 0.00 0.00 Nassarius sp. 121 0.00 0.00 5.88 10.00 10.00 0.00 Neverita reclusiana 122 1.28 0.00 0.00 0.00 0.00 0.00 Nuccella etchegoinensis 123 0.00 3.57 0.00 0.00 0.00 0.00 Nuccella funkeana 124 1.28 0.00 0.00 0.00 0.00 0.00 Olivella baetica 125 0.00 0.00 0.00 0.00 0.00 0.00 Olivella biplicata 126 0.00 0.00 0.00 0.00 0.00 0.00 Polinices lewsii 127 0.00 0.00 0.00 0.00 0.00 0.00 Pleropurpura festiva(Hinds) 128 0.00 0.00 0.00 0.00 0.00 0.00 Searlesia?sp. 129 1.28 0.00 0.00 0.00 0.00 0.00 Sinumsculpulosum 130 0.00 0.00 0.00 0.00 0.00 0.00 Siphonalia kettelmanensis 131 0.00 0.00 0.00 0.00 0.00 0.00 Thais imperialis 132Appendix C (Continued) C-40

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Appendix D

PAGE 334

D1104 110702.03 D6530 D6531 4663 110702.01 D6532 D6533 D6534 053102.01 Hoots_(1930) D6535 D6529 D1156 D1170 D6528 D1171 0 1 2 Axis 1 0 1 2 3 4 5Axis2D-1. Lower Jacalitos DCA.1 2 3 4 5 6 7

PAGE 335

D-2. Lower Jacalitosclustering of DCAaxes 1-2 scores. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 -1.9 -1.8 -1.7 -1.6 -1.5 -1.4 -1.3 -1.2 -1.1 -1 -0.9 -0.8 -0.7 -0.6 -0.5 -0.4 -0.3 -0.2 -0.1 0SimilarityD6529 4663 D6531 D6535 D6532 D1104 D1170 D6534 D6533 D1156 D6528 D6530 110702.01 053102.01 Hoots_(1930) D1171 110702.031 2 3 4 5 6 7

PAGE 336

D1104 110702.03 D6530 D6531 4663 110702.01 D6532 D6533 D6534 053102.01 Hoots_(1930) D6535 D6529 D1156 D1170 D6528 D1171 -0.2 -0.1 0 0.1 0.2 0.3 Coordinate 1 -0.4 -0.3 -0.2 -0.1 0 0.1 0.2 0.3Coordinate2D-3. Lower Jacalitos NMDS of DCAaxes 1-2 scores. Shepard Plot stress: 0.00266. 1 3 4 5 6 7 2

PAGE 337

D1105 D1106 053002.01a 4662 053002.02 D1126 110802.04 12-30-88-5 D1109 110802.05 2-21-87-2 D1107 0 1 2 3 4 5 6 7 8 9 Axis 1 0 1 2 3 4 5Axis2D-4. Upper Jacalitos DCA. 1 2 3 4 5 6 7 8

PAGE 338

D-5. Upper Jacalitosclustering of DCAaxes 1-2 scores. 1 2 3 4 5 6 7 8 9 10 11 12 13 -2 -1 0SimilarityD1109 053002.01a 53002.02 D1106 110802.04 12-30-88-5 110802.05 D1107 D1105 4662 D1126 2-21-87-22 3 4 8 5 6 7 1

PAGE 339

D1105 D1106 053002.01a 4662 53002.02 D1126 110802.04 12-30-88-5 D1109 110802.05 2-21-87-2 D1107 -0.4 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 Coordinate 1 -0.2 -0.1 0 0.1 0.2 0.3Coordinate2D-6. Upper Jacalitos NMDS of DCAaxes 1-2 scores. Shepard Plot stress: 0.00. 1 8 7 6 5 4 3 2

PAGE 340

D-7. Lower Etchegoin DCA. 2-21-87-3 D1127 D1147 052704.02 3-19-87-1 D1149 1-19-88-1 D1148 052704.04 052704.05 D1114 052704.06 052704.07a 052704.07b 052704.07c 052704.08 3-22-87-1 3-20-87-3 3-20-87-5 D1128 D1115 3-22-87-2 3-22-87-3 D1116 3-22-87-4 D1110 3-22-87-5 D1205 D1117 D1113 D1118 D1111 D1119 1-16-88-11-19-88-3 D1133 D1134 12-30-88-7 D1131 D1120 11-15-86-1 11-15-86-2 11-15-86-4 11-15-86-3 D1121 3-23-87-1 D11222-6-88-112-30-88-8 D1112 D1135 D1132 D1130 D1150 D1129 D1151 6-30-87-4 3-23-87-33-23-87-4 0 1 2 Axis 1 0 1 2 3 4 5 6 7Axis21 2 3 4 5 6

PAGE 341

D-8. Lower Etchegoinclustering of DCAaxes 1-2 scores. 10 20 30 40 50 60 -3 -2 -1 0Similarity 3-20-87-3 3-22-87-3 1-19-88-1 D1114 D1134 3-22-87-1 D1147 2-21-87-3 D1148 3-22-87-4 1-16-88-1 1-19-88-3 D1133 D1205 D1129 D1113 D1135 D1130 052704.04 D1115 D1118 D1131 11-15-86-2 3-20-87-5 D1128 D1127 3-19-87-1 052704.08 D1150 D1120 D1132 D1116 D1110 D1119 D1112 D1122 2-6-88-1 12-30-88-8 3-22-87-2 D1121 D1111 12-30-88-7 11-15-86-3 D1117 3-23-87-1 052704.02 11-15-86-1 D1149 052704.06 052704.07a D1151 052704.07b 052704.05 052704.07c 11-15-86-4 6-30-87-4 3-23-87-3 3-23-87-4 3-22-87-51 2 3 4 5 6

PAGE 342

D-9. Lower Etchegoin NMDS of DCAaxes 1-2 scores. Shepard Plot stress: 0.023. 1 2 3 4 5 6 2-21-87-3 D1127 D1147 052704.02 3-19-87-1 D1149 1-19-88-1 D1148 052704.04 052704.05 D1114 052704.06 052704.07a 052704.07b 052704.07c 052704.08 3-22-87-1 3-20-87-3 3-20-87-5 D1128 D1115 3-22-87-2 3-22-87-3 D1116 3-22-87-4 D1110 3-22-87-5 D1205 D1117 D1113 D1118 D1111 D1119 1-16-88-1 1-19-88-3 D1133 D1134 12-30-88-7 D1131 D1120 11-15-86-1 11-15-86-2 11-15-86-4 11-15-86-3 D1121 3-23-87-1 D11222-6-88-112-30-88-8 D1112 D1135 D1132 D1130 D1150 D1129 D1151 6-30-87-4 3-23-87-3 3-23-87-4 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 0.5 Coordinate 1 -0.3 -0.2 -0.1 0 0.1 0.2 0.3Coordinate2

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D-10. Upper Etchegoin (lower interval) DCA. 7 1 2 3 5 6 6-30-87-3 D1123 9-21-87-1 1-23-87-3 9-19-87-4 9-19-87-2 2-6-87-3 7-2-87-3 9-19-87-3 9-19-87-1 D1136 8-30-87-2 2-6-87-4 2-7-87-1 -0.9 -0.8 -0.7 -0.6 -0.5 -0.4 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Axis 1 1 2 3 4 5 6 7 8 9 10Axis24

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D-11. Upper Etchegoin (lower interval)clustering of DCAaxes 1-2 scores. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 -3 -2 -1 0Similarity 9-21-87-1 D1136 9-19-87-4 2-7-87-1 8-30-87-2 9-19-87-3 9-19-87-1 2-6-87-3 2-6-87-4 6-30-87-3 1-23-87-3 7-2-87-3 D1123 9-19-87-21 2 3 4 5 6 7

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1 2 3 4 5 6 7 D-12. Upper Etchegoin NMDS of DCAaxes 1-2 scores. Shepard Plot stress: 0.00. 6-30-87-3 D1123 9-21-87-1 1-23-87-3 9-19-87-4 9-19-87-2 2-6-87-3 7-2-87-3 9-19-87-3 9-19-87-1 D1136 8-30-87-2 2-6-87-4 2-7-87-1 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 Coordinate 1 -0.5 -0.4 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4Coordinate2

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D-13.zone DCA. Patinopecten D1157 021701.02 121500.02a 121500.02b 121500.02c 121500.03 309 121500.01a 121500.01b D1158 323 2-7-87-4 2-7-87-3 310 328 312 322 337 336 D1181 317a 317 B6541 330 343 320a 329 D1159 307 308 313 101301.05a D1182 B6542 314 315 342 300a 0 1 2 3 4 5 6 Axis 1 0 1 2 3 4 5Axis21 2 3 4 5 6 7 8

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D-14.zone clustering of DCAaxes 1-2 scores. Patinopecten 10 20 30 -2 -1 0Similarity B6541 D1159 -95 D1182 121500.02a D1158 121500.02b 121500.02c 328 D1157 309 B6542 121500.01a -96 101301.05a 315 121500.01b 21701.02 D1181 323 330 337 343 336 329 121500.03 310 307 308 312 317a 320a 313 314 342 300a 317 3221 2 3 4 5 6 7 8

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1 2 3 4 5 6 8 D-15.zone NMDS of DCAaxes 1-2 scores. Shepard Plot stress: 0.006. Patinopecten D1157 21701.02 121500.02a 121500.02b 121500.02c 121500.03 309 121500.01a 121500.01b D1158 323 -96 -95 310 328 312 322 337 336 D1181 317a 317 B6541 330 343 320a 329 D1159 307 308 313 101301.05a D1182 B6542 314 315 342 300a -0.2 -0.1 0 0.1 0.2 0.3 Coordinate 1 -0.2 -0.1 0 0.1 0.2 0.3 0.4Coordinate27

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D-16.zone DCA. Macoma 335 333 2-7-87-5 300a 302 305 306a 321 261 302b 300 306 D1161 D1160 2091 B6543 121401.03 D1164 D1172 D1165 D1166 D1173 D1183 0 1 2 Axis 1 0 1 2 3 4 5 6 7Axis21 2 3 4 5

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D-17.zone clustering of DCAaxes 1-2 scores. Macoma 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 -1.9 -1.8 -1.7 -1.6 -1.5 -1.4 -1.3 -1.2 -1.1 -1 -0.9 -0.8 -0.7 -0.6 -0.5 -0.4 -0.3 -0.2 -0.1 0Similarity121401.03 2-7-87-5 D1160 D1166 D1183 D1161 D1164 B6543 2091 D1165 300a D1173 302b D1172 306 305 300 333 335 306a 302 261 3211 2 3 4 5

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D-18.zone NMDS of DCAaxes 1-2 scores. Shepard Plot stress: 0.006. Macoma 335 333 2-7-87-5 300a 302 305 306a 321 261 302b 300 306 D1161 D1160 2091 B6543 121401.03 D1164 D1172 D1165 D1166 D1173 D1183 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 0.5 Coordinate 1 -0.1 0 0.1 0.2 0.3Coordinate21 2 3 4 5

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D-19.zone DCA. Siphonalia 279 7-3-87-4 7-3-87-1 7-3-87-2 D1162 264 265 268 D1174 8-29-87-1 8-29-87-2a 8-29-87-2b 8-29-87-3 111800.03 288 D1175 B6544 110702.06 D1152 267 292 282 D1180 286 287 284 B6545 052802.04 266 270 257 278a 111800.02 258 D1176 274 D1168 D1167 D1137 110702.07 121401.01a 238b 264a 290 280 269 274a 101301.02a B6546 256 255 294 272 237 283 259 D1169 299 D1138 281271 278 030202.06 052802.05 275a B6547 2093 D1177 100700.01 100700.02100700.03 100700.04 052802.06b D1178 B6548 110702.08 100299.01 D1153 D1139 052802.07 101301.08a 0 1 2 3 4 5 6 7 Axis 1 0 1 2 3 4 5Axis26 1 2 3 4 5

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D-20.zone clustering of DCAaxes 1-2 scores. Siphonalia 10 20 30 40 50 60 70 80 -2 -1 0Similarity7-3-87-1 8-29-87-2a D1168 D1153 111800.02 7-3-87-2 D1162 8-29-87-2b 290 B6545 278 258 275a B6546 264 270 256 294 266 288 259 268 267 282 292 284 D1176 283 269 274 D1180 287 264a 238b 272 299 D1177 D1178 B6547 8-29-87-1 8-29-87-3 D1139 255 265 278a 274a 280 279 D1174 110702.08 111800.03 D1152 052802.05 052802.04 110702.06 101301.08a 286 257 281 271 030202.06 100700.04 100700.01 121401.01a 100299.01 D1175 237 D1137 100700.02 100700.03 052802.06b 101301.02a 052802.07 B6544 D1167 110702.07 2093 D1169 B6548 D1138 7-3-87-46 1 2 3 4 5

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D-21.zone NMDS of DCAaxes 1-2 scores. Shepard Plot stress: 0.031. Siphonalia 279 7-3-87-4 7-3-87-1 7-3-87-2 D1162 264 265 268 D1174 8-29-87-1 8-29-87-2a 8-29-87-2b 8-29-87-3 111800.03 288 D1175 B6544 110702.06 D1152 267 292 282 D1180 286 287 284 B6545 052802.04 266 270 257 278a 111800.02 258 D1176 274 D1168 D1167 D1137 110702.07 121401.01a 238b 264a 290 280 269 274a 101301.02a B6546 256 255 294 272 237 283 259 D1169 299 D1138 281271 278 030202.06 052802.05 275a B6547 2093 D1177 100700.01 100700.02100700.03 100700.04 052802.06b D1178 B6548 110702.08 100299.01 D1153 D1139 052802.07 101301.08a -0.1 0 0.1 0.2 Coordinate 1 -0.2 -0.1 0 0.1 0.2Coordinate26 1 2 3 4 5

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D-22.zone DCA. Pseudocardium D1140 252 101301.01c 101301.08b 101301.08c 101301.08d D1141 248 243a 247 250 251 239b 244 239 252a 242243 249 245 238 241 D1142 253 9-20-87-1 8-11-87-19-20-87-2 021701.01 111800.01a 111800.01b 111800.01c 0 1 2 Axis 1 0 1 2 3 4 5 6 7Axis26 1 2 3 4 5

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D-23.zone clustering of DCAaxes 1-2 scores. Pseudocardium 10 20 30 -1.9 -1.8 -1.7 -1.6 -1.5 -1.4 -1.3 -1.2 -1.1 -1 -0.9 -0.8 -0.7 -0.6 -0.5 -0.4 -0.3 -0.2 -0.1 0Similarity238 253 021701.01 D1140 D1141 D1142 247 111800.01b 101301.08b 251 101301.08d 248 252 101301.01c 252a 245 250 243a 244 242 243 249 241 101301.08c 9-20-87-1 111800.01a 239b 111800.01c 239 8-11-87-1 9-20-87-26 1 2 3 4 5

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D-24.zone NMDS of DCAaxes 1-2 scores. Shepard Plot stress: 0.007. Pseudocardium D1140 252101301.01c 101301.08b 101301.08c 101301.08d D1141 248 243a 247 250 251 239b 244 239 252a 242 243 249 245 238 241 D1142 253 9-20-87-1 8-11-87-1 9-20-87-2 021701.01 111800.01a 111800.01b 111800.01c -0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 0.5 0.6 Coordinate 1 -0.2 -0.1 0 0.1 0.2 0.3Coordinate21 2 3 4 5 6

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D-25.zone DCA. Littorina D1143 240 239a D1154 B6527 D1144 223 238a 218 D1124 D1155 229 226 D1145 225 D1146 D1125 227219 221 0 1 2 3 4 5 6 7 Axis 1 0 1 2 3 4Axis21 2 3 4 5 6 7

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D-26.zone clustering of DCAaxes 1-2 scores. Littorina 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 -2 -1 0SimilarityD1145 B6527 223 229 221 239a 238a 226 240 218 225 227 219 D1144 D1155 D1124 D1146 D1125 D1143 D11541 2 3 4 5 6 7

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D-27.zone NMDS of DCAaxes 1-2 scores. Shepard Plot Stress: 0.005. Littorina D1143 240 239a D1154 B6527 D1144 223 238a 218 D1124 D1155 229 226 D1145 225 D1146 D1125 227219 221 -0.1 0 0.1 0.2 0.3 0.4 Coordinate 1 -0.5 -0.4 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4Coordinate27 6 5 4 3 2 1

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1 2 3 4 5 6 7 D-28. Cascajo Conglomerate DCA. 206 208209210211 212 213 214 215 216 1-20-89-3 053002.03 203 060701.01 185 183 204 194 197 202 201 198 111700.01 D1193 177 051599.01 D1087 175 178 D1187 D1194 2092 171 162 157 146 146a 192 0 1 2 Axis 1 0 1 2 3 4 5 6 7 8 9 10Axis2

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D-29. Cascajo Conglomerateclustering of DCAaxes 1-2 scores. 10 20 30 -2 -1 0Similarity177 178 1-20-89-3 2092 194 146 053002.03 202 192 060701.01 157 171 185 201 211 208 209 210 212 216 183 111700.01 204 D1193 175 051599.01 D1187 D1194 214 198 203 197 213 215 D1087 206 162 146a4 7 6 5 3 2 1

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D-30. Cascajo Conglomerate NMDS of DCAaxes 1-2 scores. Shepard Plot stress: 0.005. 206 208209210211 212 213 214 215 216 1-20-89-3 053002.03 203 060701.01 185 183 204 194 197 202 201 198 111700.01 D1193 177 051599.01 D1087 175 178 D1187 D1194 2092 171 162 157 146 146a 192 -0.2 -0.1 0 0.1 0.2 0.3 0.4 0.5 0.6 Coordinate 1 0 0.1 0.2Coordinate21 2 3 4 5 6 7

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D-31.zone DCA. Neverita 1 2 3 4 5 6 7 163 170 172 155 101301.06 D1188 156 149150 161 158 148 148a 153 154 152 151 145 165 7-21-87-1 D1189 D1190 D1184 0 1 2 Axis 1 0 1 2 3 4 5 6 7Axis2

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D-32.zone clustering of DCAaxes 1-2 scores. Neverita 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 -2 -1 0Similarity 151 101301.06 158 D1189 161 152 149 150 148a 154 148 153 163 145 165 D1188 D1190 170 156 172 7-21-87-1 155 D11841 2 3 4 5 6 7

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1 2 3 4 5 6 D-33.zone NMDS of DCAaxes 1-2 scores. Shepard Plot stress: 0.008. Neverita 163 170 172 155 101301.06 D1188 156 149150 161 158 148 148a 153 154 152 151 145 165 7-21-87-1 D1189 D1190 D1184 -0.2 -0.1 0 0.1 0.2 0.3 0.4 0.5 0.6 Coordinate 1 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4Coordinate27

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1 2 3 4 5 D-34.zone DCA. Pecten 052902.04 110702.09 112 D1203 D1191 103a 119a 106 105a 77 79 74 81 80 71 103 107 86 108 93a 124 92 110 115 119 118 91 76114 73 83 B6539 102 109 117 130 104 101 87 113 D1196 85 84 102b94 98 97 82 B6538 116 93 102a B6537 105 140a 140b 99 89 114a 140 78 111 139 75 120 138 0 1 2 Axis 1 0 1 2 3 4 5 6 7 8 9 10Axis2

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D-35.zone clustering of DCAaxes 1-2 scores. Pecten 10 20 30 40 50 60 -4 -3 -2 -1 0Similarity103a 113 87 110702.09 117 114a 85 99 97 74 118 89 91 98 119a 124 76 82 114 86 052902.04 83 109 130 116 73 84 93 105a 92 107 102 102a 102b 94 119 106 140 75 77 104 103 120 108 105 111 93a 110 101 79 D1196 140a 115 80 71 81 B6539 140b 138 D1203 B6538 B6537 112 78 D1191 1391 2 3 4 5

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D-36.zone NMDS of DCAaxes 1-2 scores. Shepard Plot stress: 0.085. Pecten 1 2 3 4 5 052902.04 110702.09 112 D1203 D1191 103a 119a 106 105a 77 79 74 81 80 71 103 107 86 108 93a 124 92 110 115 119 118 91 76 114 73 83 B6539 102 109 117 130 104 101 87 113 D1196 85 84 102b 94 98 97 82 B6538 116 93 102a B6537 105 140a 140b 99 89 114a 140 78 111 139 75 120 138 -0.4 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 0.5 Coordinate 1 -0.4 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 0.5Coordinate2

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D-37.zone DCA. Trachycardium 130b 132 72 130a 102c 123 127 121 130c 135 D1197 100 128 D1198 D1201 0 1 2 3 4 5 6 7 8 9 10 Axis 1 0 1 2 3 4 5Axis21 2 3 4 5 6

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D-38.zone clustering of DCAaxes 1-2 scores. Trachycardium 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 -5 -4 -3 -2 -1 0SimilarityD1201 D1197 D1198 102c 100 121 132 128 135 130a 130b 130c 123 127 726 1 2 3 4 5

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130b 132 72 130a 102c 123 127 121 130c 135 D1197 100 128 D1198 D1201 -0.2 -0.1 0 0.1 0.2 0.3 0.4 0.5 0.6 Coordinate 1 -0.9 -0.8 -0.7 -0.6 -0.5 -0.4 -0.3 -0.2 -0.1 0 0.1 0.2 0.3Coordinate2D-39.zone NMDS of DCAaxes 1-2 scores. Shepard Plot stress: 0.010. Trachycardium 6 1 2 3 4 5

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6 1 2 3 4 5 D-40.zone DCA. Acila 57 57a 58 59 60 61 62 63 64 64a 65 66 67 68 D1200 B6540 D1185 D1192 110702.10 0 1 2 3 4 5 6 7 8 Axis 1 0 1 2 3 4Axis2

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D-41.zone clustering of DCAaxes 1-2 scores. Acila 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 -3 -2 -1 0SimilarityD1192 57a 67 57 63 62 66 68 60 64 64a 65 58 110702.10 61 D1200 B6540 D1185 596 1 2 3 4 5

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6 1 2 3 4 5 D-42.zone NMDS of DCAaxes 1-2 scores. Shepard Plot stress: 0.0034. Acila 60 59 57a D1200 67 64 58 66 B6540 63 110702.10 62 64a 65 57 D1185 68 D1192 61 -0.3 -0.2 -0.1 0 0.1 0.2 Coordinate 1 -0.5 -0.4 -0.3 -0.2 -0.1 0 0.1 0.2 0.3Coordinate2

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7 6 1 2 3 4 5 8 D-43. Upperzone DCA. Mya 48 55 5054535251 47 3729 2376 32 41 38 31 33 D2089 30 40 36 39 061001.01 35 42 43 4445 46 0 1 2 3 4 5 6 7 8 Axis 1 0 1 2 3 4 5Axis2

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D-44. Upperclustering of DCAaxes 1-2 scores. Mya 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 -4 -3 -2 -1 0Similarity D2089 41 42 40 35 55 43 36 061001.01 44 45 47 32 31 30 2376 37 51 52 53 50 48 54 29 38 33 46 397 6 1 2 3 4 5 8

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7 6 1 2 3 4 5 8 D-45. Upperzone NMDS of DCAaxes 1-2 scores. Shepard Plot stress: 0.059. Mya 48 55 5054 5352 51 47 3729 2376 32 41 38 31 33 D2089 30 40 36 39 061001.01 35 42 43 4445 46 -0.1 0 0.1 0.2 0.3 0.4 Coordinate 1 -0.1 0 0.1 0.2 0.3 0.4 0.5 0.6Coordinate2

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Appendix E

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DC2 DC1 ET HT SE ST Temp(C) Depth (m) Community Level (m) Locality No. 1.281 -0.005 0.863 2.686 6 17 13.9 9.7 1 5 D1104 1 3.337 -0.005 0.827 2.755 6 19 13.6 4.3 3 8 110702.03 2 1.844 -0.005 0.862 2.490 5 14 13.8 8.2 3 8 D6530 3 1.028 -0.005 0.845 2.776 5 19 12.9 10.3 1 12 D6531 4 1.618 1.000 0.000 0.000 0 1 10.6 8.8 3 15 4663 5 1.569 -0.005 0.790 2.249 2 12 13.8 8.9 3 17 110702.01 6 1.280 -0.005 0.876 2.353 1 12 13.0 9.7 1 17 D6532 7 1.145 -0.005 0.895 2.454 4 13 12.9 10.0 1 20 D6533 8 1.218 -0.005 0.949 2.145 3 9 13.7 9.8 1 25 D6534 9 4.045 -0.005 0.750 2.351 5 14 11.8 2.5 3 25 053102.01 10 3.858 -0.005 0.883 1.667 2 6 11.0 3.0 3 25 Hoots_(1930) 11 0.918 -0.005 0.959 2.038 2 8 12.2 10.6 1 26 D6535 12 -0.000 -0.005 0.762 2.562 5 17 12.7 13.0 2 43 D6529 13 0.695 -0.005 0.987 1.373 1 4 12.6 11.2 2 47 D1156 14 1.276 -0.005 0.959 2.356 4 11 12.6 9.7 1 47 D1170 15 0.621 -0.005 0.806 2.423 5 14 13.5 11.4 2 49 D6528 16 3.776 -0.005 0.928 0.618 0 2 11.2 3.2 3 49 D1171 17 1.172 2.457 0.939 1.729 1 6 12.9 13.3 2 219 D1105 18 -0.000 1.666 0.939 1.036 1 3 13.9 18.0 3 225 D1106 19 0.747 4.091 0.878 1.479 0 5 11.8 15.0 3 230 053002.01a 20 0.251 7.868 0.772 1.533 0 6 13.3 17.0 3 270 4662 21 0.753 4.262 0.863 2.251 3 11 12.1 15.0 3 320 053002.02 22 3.862 7.374 0.756 1.106 1 4 11.5 2.5 3 399 D1126 23 2.194 -0.000 0.792 1.713 3 7 13.6 9.2 2 436 110802.04 24 2.300 0.935 0.938 1.322 1 4 13.9 8.8 2 436 12-30-88-5 25 4.394 2.182 0.878 0.563 1 2 13.1 0.4 7 546 D1109 26 3.562 0.977 0.000 0.000 0 1 15.5 3.7 2 546 110802.05 27 4.498 4.384 0.826 0.908 3 3 12.2 0.0 7 616 2-21-87-2 28 2.126 0.984 0.987 1.086 0 3 13.2 9.5 2 617 D1107 29 0.483 -0.003 0.000 0.000 0 1 13.9 11.5 1 659 2-21-87-3 30 1.578 -0.003 0.715 1.610 4 7 12.6 9.4 1 695 D1127 31 0.475 -0.003 0.797 1.970 2 9 11.4 11.6 1 725 D1147 32 0.000 -0.003 0.000 0.000 0 1 13.9 12.5 4 796 052704.02 33 1.564 -0.003 0.622 0.219 1 2 12.6 9.4 1 842 3-19-87-1 34 2.358 -0.003 0.690 1.015 1 4 14.9 7.8 1 915 D1149 35Appendix E E-1

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DC2 DC1 ET HT SE ST Temp(C) Depth (m) Community Level (m) Locality No. 0.578 -0.003 0.939 1.036 2 3 11.8 11.3 1 927 1-19-88-1 36 0.404 -0.003 0.979 1.588 1 5 14.0 11.7 1 931 D1148 37 1.315 -0.003 0.886 1.488 1 5 11.0 9.9 1 932 052704.04 38 1.801 -0.003 0.878 0.563 0 2 11.1 8.9 2 932 052704.05 39 0.658 -0.003 0.839 1.434 1 5 13.1 11.2 1 933 D1114 40 2.429 -0.003 0.773 1.688 2 7 12.8 7.7 1 934.3 052704.06 41 2.905 -0.003 0.661 1.378 1 6 11.5 6.7 1 934.5 052704.07a 42 2.682 -0.003 0.703 1.593 3 7 12.2 7.2 1 934.7 052704.07b 43 1.798 -0.003 0.686 1.820 4 9 12.0 8.9 2 935.0 052704.07c 44 1.237 -0.003 0.789 2.066 4 10 12.2 10.0 1 935.6 052704.08 45 0.695 -0.003 1.001 0.694 1 2 14.7 11.1 1 957 3-22-87-1 46 5.628 -0.003 0.909 0.598 1 2 9.9 1.3 6 970 3-20-87-3 47 1.505 -0.003 0.755 0.817 2 3 14.8 9.5 1 991 3-20-87-5 48 1.447 -0.003 0.829 1.199 1 4 11.9 9.6 1 1004 D1128 49 1.339 -0.003 0.757 1.331 2 5 13.1 9.8 1 1004 D1115 50 1.038 -0.003 0.662 1.985 3 11 12.4 10.4 1 1009 3-22-87-2 51 6.279 -0.003 0.000 0.000 1 1 10.3 0.0 6 1009 3-22-87-3 52 1.122 -0.003 0.730 2.393 6 15 12.2 10.3 1 1014 D1116 53 0.857 -0.003 0.808 1.866 1 8 12.7 10.8 1 1027 3-22-87-4 54 1.150 -0.003 0.808 1.396 2 5 12.0 10.2 1 1044 D1110 55 2.117 1.000 0.000 0.000 0 1 11.5 8.3 2 1046 3-22-87-5 56 0.803 -0.003 0.754 2.426 5 15 12.3 10.9 1 1049 D1205 57 1.079 -0.003 0.858 1.793 2 7 14.3 10.4 1 1065 D1117 58 0.819 -0.003 0.851 1.225 0 4 10.6 10.9 1 1093 D1113 59 1.344 -0.003 0.723 2.240 6 13 11.9 9.8 1 1096 D1118 60 0.985 -0.003 0.777 2.232 2 12 12.0 10.5 1 1100 D1111 61 1.147 -0.003 0.712 1.858 3 9 12.1 10.2 1 1107 D1119 62 0.891 -0.003 0.000 0.000 1 1 10.7 10.7 1 1107 1-16-88-1 63 0.891 -0.003 0.000 0.000 1 1 10.7 10.7 1 1107 1-19-88-3 64 0.909 -0.003 0.766 2.131 2 11 13.0 10.7 1 1120 D1133 65 0.628 -0.003 0.753 2.355 4 14 12.0 11.2 1 1126 D1134 66 1.015 -0.003 0.938 1.035 3 3 12.2 10.5 1 1128 12-30-88-7 67 1.385 -0.003 0.768 0.429 1 2 14.2 9.7 1 1131 D1131 68 1.199 -0.003 0.694 1.714 3 8 11.6 10.1 1 1165 D1120 69 0.157 -0.003 0.000 0.000 0 1 15.5 12.2 4 1171 11-15-86-1 70Appendix E (Continued) E-2

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DC2 DC1 ET HT SE ST Temp(C) Depth (m) Community Level (m) Locality No. 1.383 -0.003 0.795 0.464 2 2 11.5 9.7 1 1171 11-15-86-2 71 1.004 -0.003 0.705 1.442 2 6 12.1 10.5 1 1171 11-15-86-3 72 1.774 -0.003 0.975 1.073 2 3 11.5 9.0 2 1171 11-15-86-4 73 1.037 -0.003 0.716 1.969 4 10 12.7 10.4 1 1177 D1121 74 1.083 -0.003 0.779 1.360 3 5 13.0 10.3 1 1180 3-23-87-1 75 1.173 -0.003 0.867 1.803 2 7 11.8 10.2 1 1184 D1122 76 1.167 -0.003 0.727 0.780 1 3 10.5 10.2 1 1186 2-6-88-1 77 1.167 -0.003 0.727 0.780 1 3 10.5 10.2 1 1186 12-30-88-8 78 1.153 -0.003 0.785 2.466 4 15 12.4 10.2 1 1189 D1112 79 0.760 -0.003 0.592 1.778 3 10 12.3 11.0 1 1189 D1135 80 1.214 -0.003 0.736 1.773 1 8 10.8 10.1 1 1205 D1132 81 0.754 -0.003 0.629 1.146 1 5 11.9 11.0 1 1210 D1130 82 1.249 -0.003 0.752 1.507 1 6 11.8 10.0 1 1211 D1150 83 0.797 -0.003 0.662 1.890 4 10 12.2 10.9 1 1216 D1129 84 2.894 -0.003 0.793 0.867 1 3 10.6 6.7 1 1234 D1151 85 1.984 -0.003 0.571 0.133 1 2 14.5 8.5 2 1234 6-30-87-4 86 2.017 -0.003 0.000 0.000 1 1 12.1 8.5 2 1234 3-23-87-3 87 2.017 -0.003 0.000 0.000 1 1 12.1 8.5 2 1234 3-23-87-4 88 4.894 1.000 0.000 0.000 1 1 11.5 11.5 1 1274 6-30-87-3 89 9.422 -0.024 0.944 0.636 0 2 10.6 4.6 5 1329 D1123 90 2.243 -0.024 0.944 0.636 0 2 11.4 15.6 3 1390 9-21-87-1 91 -0.000 -0.024 0.794 0.868 0 3 13.4 19.0 2 1399 1-23-87-3 92 3.714 -0.024 0.929 1.718 1 6 11.9 13.3 1 1437 9-19-87-4 93 7.866 -0.024 0.867 0.956 1 3 10.9 7.0 1 1437 9-19-87-2 94 5.307 -0.024 0.885 1.264 0 4 13.2 10.9 3 1439 2-6-87-3 95 0.659 -0.024 0.825 0.501 1 2 13.0 18.0 2 1439 7-2-87-3 96 4.511 -0.024 0.825 0.501 0 2 11.1 12.1 1 1439 9-19-87-3 97 4.458 -0.024 0.937 1.544 1 5 12.1 12.2 1 1439 9-19-87-1 98 2.639 -0.024 0.739 0.796 1 3 13.1 15.0 3 1443 D1136 99 3.257 -0.024 0.821 0.901 2 3 11.4 14.0 1 1451 8-30-87-2 100 5.870 -0.024 0.867 0.956 0 3 10.8 10.0 3 1454 2-6-87-4 101 3.774 -0.024 0.821 0.901 2 3 12.8 13.2 1 1454 2-7-87-1 102 2.035 3.048 0.880 1.259 0 4 11.3 14.3 1 1472 D1157 103 0.231 3.521 0.639 1.161 2 5 11.6 23.8 1 1475 021701.02 104 1.920 2.261 0.927 1.023 1 3 11.8 14.9 1 1482 121500.02a 105Appendix E (Continued) E-3

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DC2 DC1 ET HT SE ST Temp(C) Depth (m) Community Level (m) Locality No. 2.047 2.042 0.000 0.000 1 1 12.1 14.2 1 1482 121500.02b 106 2.047 2.042 0.000 0.000 1 1 12.1 14.2 1 1482 121500.02c 107 2.509 1.949 0.771 1.820 4 8 11.9 11.8 1 1497 121500.03 108 1.865 1.379 0.729 0.377 1 2 11.2 15.2 2 1506 309 109 0.872 2.002 0.714 2.061 3 11 12.0 20.4 2 1508 121500.01a 110 0.000 2.479 0.671 1.798 2 9 11.9 25.0 1 1509 121500.01b 111 1.835 2.465 0.940 1.548 2 5 11.9 15.3 1 1513 D1158 112 2.839 3.653 1.000 0.693 1 2 11.5 10.0 4 1517 323 113 0.730 2.019 0.000 0.000 0 1 11.4 21.1 2 1518 2-7-87-4 114 1.211 2.575 0.963 1.349 1 4 13.1 18.6 1 1518 2-7-87-3 115 2.872 2.017 0.881 0.972 1 3 13.2 9.8 1 1518 310 116 2.167 2.663 0.788 1.553 3 6 12.1 13.6 1 1518 328 117 3.499 2.429 0.858 1.233 3 4 11.9 6.5 1 1518 312 118 1.896 5.738 0.520 0.444 0 3 11.8 15.0 2 1519 322 119 3.154 3.148 0.800 1.386 4 5 11.9 8.4 4 1524 337 120 2.910 2.916 0.890 1.270 3 4 13.5 9.6 4 1524 336 121 0.576 3.231 0.710 1.044 0 4 12.5 22.0 1 1524 D1181 122 3.520 2.021 0.000 0.000 0 1 10.7 6.4 1 1536 317a 123 4.737 2.736 0.639 0.245 1 2 11.1 0.0 6 1536 317 124 2.015 0.462 0.641 2.813 8 26 11.9 14.4 1 1536 B6541 125 3.026 3.457 0.770 1.348 2 5 11.9 9.0 4 1537 330 126 3.347 3.047 0.852 1.226 1 4 11.0 7.3 4 1537 343 127 3.520 2.021 0.000 0.000 0 1 10.7 6.4 1 1537 320a 128 2.823 2.735 0.846 1.624 3 6 12.1 10.1 4 1537 329 129 1.545 0.000 0.690 1.708 2 8 12.0 16.8 1 1539 D1159 130 2.874 2.036 0.856 1.231 1 4 11.2 9.8 1 1540 307 131 2.682 1.344 0.714 1.272 1 5 13.5 10.8 1 1540 308 132 3.520 2.021 0.724 1.757 2 8 12.3 6.4 1 1541 D1182 133 1.030 1.768 0.000 0.000 0 1 10.7 19.6 1 1541 313 134 1.233 2.959 0.729 0.377 1 2 11.3 18.5 2 1541 101301.05a 135 1.755 1.375 0.726 2.513 5 17 11.4 15.7 2 1542 B6542 136 3.520 2.021 0.000 0.000 0 1 10.7 6.4 1 1544 314 137 1.219 1.656 0.000 0.000 1 1 13.3 18.6 2 1544 315 138 3.520 2.021 0.000 0.000 0 1 10.7 6.4 1 1545 342 139 3.274 2.150 0.768 2.038 4 10 12.8 7.7 1 1545 300a 140Appendix E (Continued) E-4

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DC2 DC1 E T H T S E S T Temp(C) Depth (m) Community Level (m) Locality No. 3.307 -0.009 0.750 1.098 2 4 13.1 5.3 5 1546 335 141 2.972 -0.009 0.000 0.000 1 1 15.5 5.9 5 1546 333 142 1.283 -0.009 0.000 0.000 0 1 11.4 9.2 1 1546 2-7-87-5 143 4.238 -0.009 0.926 1.022 1 3 11.1 3.5 5 1546 300a 144 5.409 -0.009 0.974 0.667 2 2 11.2 1.3 7 1546 302 145 3.610 -0.009 1.001 0.694 1 2 15.5 4.7 5 1546 305 146 3.011 1.000 0.000 0.000 0 1 10.1 5.9 2 1546 306a 147 6.087 -0.009 0.000 0.000 1 1 10.3 0.0 7 1546 321 148 5.409 -0.009 0.974 0.667 2 2 11.2 1.3 7 1547 261 149 4.419 -0.009 0.825 0.501 1 2 13.8 3.2 5 1548 302b 150 3.786 -0.009 0.960 1.058 1 3 11.7 4.4 5 1548 300 151 4.566 -0.009 0.888 1.268 3 4 12.5 2.9 5 1550 306 152 2.317 -0.009 0.905 1.286 0 4 11.1 7.2 1 1550 D1161 153 1.689 -0.009 0.759 1.804 3 8 12.6 8.4 1 1550 D1160 154 2.430 -0.009 0.679 2.748 7 23 11.6 7.0 1 1551 2091 155 2.185 -0.009 0.800 2.080 1 10 11.7 7.4 1 1553 B6543 156 -0.000 -0.009 0.783 1.701 0 7 11.9 11.6 4 1553 121401.03 157 2.257 -0.009 0.918 1.524 0 5 12.4 7.3 1 1560 D1164 158 4.423 -0.009 0.825 0.501 1 2 13.0 3.2 5 1563 D1172 159 2.459 -0.009 0.786 1.957 1 9 12.1 6.9 1 1565 D1165 160 1.562 -0.009 0.753 1.796 2 8 11.9 8.6 1 1565 D1166 161 4.093 -0.009 0.898 0.586 1 2 11.1 3.8 5 1566 D1173 162 1.816 -0.009 0.767 1.121 0 4 11.1 8.1 1 1568 D1183 163 1.270 0.770 0.777 1.134 0 4 12.0 8.3 1 1569 279 164 4.118 3.951 0.568 0.127 0 2 10.8 0.0 7 1570 7-3-87-4 165 1.474 3.110 0.644 1.862 5 10 11.8 7.7 1 1570 7-3-87-1 166 1.493 2.628 0.789 1.373 2 5 12.2 7.6 1 1570 7-3-87-2 167 1.608 2.819 0.831 0.914 0 3 11.5 7.3 1 1569 D1162 168 1.439 1.611 0.778 1.828 1 8 12.6 7.8 1 1570 264 169 0.203 1.140 0.000 0.000 0 1 17.0 11.4 1 1570 265 170 0.669 1.531 0.801 1.164 0 4 12.5 10.0 1 1571 268 171 0.752 4.380 0.766 0.427 1 2 11.1 9.8 1 1571 D1174 172 2.034 3.530 0.787 0.859 1 3 12.5 6.1 2 1571 8-29-87-1 173 1.442 2.937 0.721 1.619 1 7 11.9 7.8 1 1571 8-29-87-2a 174 1.021 2.960 0.778 1.541 0 6 12.1 9.0 1 1571 8-29-87-2b 175Appendix E (Continued) E-5

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DC2 DC1 ET HT SE ST Temp(C) Depth (m) Community Level (m) Locality No. 2.241 3.057 0.692 1.018 2 4 12.5 5.5 2 1571 8-29-87-3 176 1.026 4.059 0.619 2.086 4 13 12.7 9.0 1 1572 111800.03 177 1.213 1.221 0.000 0.000 1 1 13.9 8.5 1 1575 288 178 1.212 5.138 0.608 0.195 1 2 11.2 8.5 1 1574 D1175 179 0.357 3.815 0.613 2.218 7 15 11.8 11.0 1 1574 B6544 180 1.143 3.952 0.778 1.828 1 8 11.9 8.7 1 1574 110702.06 181 0.907 4.039 0.751 2.111 3 11 11.8 9.4 1 1576 D1152 182 0.825 1.662 0.877 0.967 0 3 11.0 9.6 1 1576 267 183 1.304 2.426 0.783 1.701 5 7 13.3 8.2 1 1576 292 184 0.796 1.165 0.774 0.842 0 3 13.1 9.7 1 1578 282 185 1.195 2.191 0.778 2.234 3 12 12.5 8.5 1 1577 D1180 186 1.178 4.126 0.000 0.000 1 1 12.1 8.6 1 1579 286 187 1.287 2.085 0.739 2.336 6 14 12.1 8.2 1 1579 287 188 1.378 2.203 0.788 1.708 2 7 12.5 8.0 1 1579 284 189 0.835 2.942 0.664 2.481 4 18 12.2 9.6 1 1582 B6545 190 0.868 4.125 0.685 1.819 1 9 11.3 9.5 1 1582 052802.04 191 1.684 1.597 0.706 1.731 3 8 12.2 7.1 1 1583 266 192 1.401 1.812 0.837 1.901 3 8 12.1 7.9 1 1583 270 193 1.178 4.126 0.000 0.000 1 1 12.1 8.6 1 1586 257 194 1.481 0.000 0.000 0.000 0 1 14.6 7.7 1 1586 278a 195 1.549 3.425 0.616 1.125 2 5 11.6 7.5 1 1586 111800.02 196 0.291 2.632 0.000 0.000 0 1 10.6 11.2 1 1587 258 197 1.525 2.182 0.851 1.631 3 6 11.9 7.6 1 1586 D1176 198 1.712 2.242 0.859 1.234 1 4 12.8 7.0 1 1588 274 199 1.326 3.166 0.765 1.678 1 7 11.7 8.1 1 1588 D1168 200 0.411 3.675 0.978 1.364 2 4 12.1 10.8 1 1588 D1167 201 1.037 4.732 0.629 1.934 3 11 11.6 9.0 1 1588 D1137 202 0.610 3.849 0.744 2.090 0 11 11.5 10.2 1 1588 110702.07 203 1.760 4.051 0.764 1.110 1 4 12.7 6.9 1 1588 121401.01a 204 0.883 2.157 0.670 0.986 1 4 11.9 9.4 1 1589 238b 205 1.195 1.916 0.740 2.471 4 16 12.4 8.5 1 1589 264a 206 0.496 2.909 0.576 2.706 4 26 12.3 9.0 1 1589 B6546 207 1.031 3.025 0.791 1.375 1 5 13.1 8.3 1 1590 290 208 1.262 0.934 0.810 1.399 1 5 11.8 7.7 1 1590 280 209 1.471 2.340 0.887 1.672 0 6 11.6 8.5 1 1590 269 210Appendix E (Continued) E-6

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DC2 DC1 ET HT SE ST Temp(C) Depth (m) Community Level (m) Locality No. 1.198 0.299 0.000 0.000 1 1 10.3 9.4 1 1590 274a 211 0.905 4.939 0.651 0.670 5 3 11.8 10.6 1 1590 101301.02a 212 1.232 1.665 0.859 2.246 4 11 12.7 8.4 1 1591 256 213 2.324 2.333 0.849 0.529 0 2 14.1 5.2 2 1591 255 214 1.232 1.591 0.000 0.000 1 1 11.0 8.4 1 1591 294 215 0.986 2.054 0.000 0.000 0 1 12.1 9.1 1 1591 272 216 1.144 5.124 0.591 0.860 2 4 11.8 8.7 1 1592 237 217 1.511 2.176 0.772 1.533 2 6 11.9 7.6 1 1592 283 218 1.246 1.386 0.826 1.888 2 8 11.1 8.4 1 1592 259 219 0.000 4.234 0.597 1.682 6 9 12.9 12.0 1 1592 D1169 220 0.986 2.054 0.000 0.000 0 1 12.1 9.1 1 1594 299 221 1.318 5.853 0.439 1.257 2 8 12.0 8.2 2 1594 D1138 222 1.178 4.126 0.000 0.000 1 1 12.1 8.6 1 1595 281 223 1.178 4.126 0.000 0.000 1 1 12.1 8.6 1 1595 271 224 0.929 2.945 0.906 1.000 2 3 13.2 9.3 1 1595 278 225 1.178 4.126 0.000 0.000 1 1 12.1 8.6 1 1595 030202.06 226 0.917 4.013 0.801 1.724 1 7 12.4 9.3 1 1595 052802.05 227 0.186 2.764 0.000 0.000 0 1 13.5 11.5 1 1596 275a 228 1.046 2.326 0.742 2.100 2 11 12.4 9.0 1 1597 B6547 229 0.688 3.684 0.622 2.165 3 14 12.2 10.0 1 1598 2093 230 0.986 2.054 0.000 0.000 0 1 12.1 9.1 1 1600 D1177 231 1.190 4.246 0.681 0.715 2 3 10.8 8.5 1 1601 100700.01 232 1.033 4.755 0.847 0.527 1 2 10.8 9.0 1 1601 100700.02 233 1.033 4.755 0.847 0.527 1 2 10.8 9.0 1 1601 100700.03 234 1.178 4.126 0.000 0.000 1 1 12.1 8.6 1 1601 100700.04 235 1.118 4.651 0.673 1.801 3 9 12.4 8.7 1 1601 052802.06b 236 0.986 2.054 0.000 0.000 0 1 12.1 9.1 1 1601 D1178 237 0.107 4.079 0.575 2.012 2 13 11.9 11.7 1 1601 B6548 238 1.028 4.366 0.739 2.336 3 14 12.3 9.0 1 1604 110702.08 239 1.421 3.824 0.785 1.703 1 7 12.1 7.9 1 1605 100299.01 240 1.328 3.251 0.686 1.703 1 8 12.1 8.1 1 1607 D1153 241 2.477 2.769 0.489 0.670 2 4 13.4 4.8 2 1608 D1139 242 1.604 4.526 0.787 1.147 2 4 12.1 7.3 1 1608 052802.07 243 0.973 3.862 0.642 1.860 2 10 12.2 9.2 1 1612 101301.08a 244 5.271 -0.018 0.779 0.849 1 3 13.1 3.0 5 1616 D1140 245Appendix E (Continued) E-7

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DC2 DC1 ET HT SE ST Temp(C) Depth (m) Community Level (m) Locality No. 3.724 -0.018 0.000 0.000 0 1 16.8 6.0 2 1616 252 246 3.708 -0.018 0.688 1.706 1 8 12.6 6.0 2 1617 101301.01c 247 1.413 -0.018 0.653 1.183 1 5 10.8 10.3 2 1618 101301.08b 248 2.942 -0.018 0.800 0.876 1 3 10.6 7.4 2 1619 101301.08c 249 0.000 -0.018 0.601 1.100 1 5 11.3 13.0 2 1620 101301.08d 250 6.241 -0.018 0.580 0.841 2 4 11.2 1.2 5 1620 D1141 251 3.790 -0.018 0.732 1.480 1 6 11.8 5.8 2 1620 248 252 3.276 -0.018 0.884 0.570 1 2 10.8 6.8 2 1620 243a 253 2.079 -0.018 0.607 1.293 3 6 11.3 9.1 2 1620 247 254 4.000 -0.018 0.672 2.001 2 11 11.8 5.4 2 1620 250 255 0.986 -0.018 0.646 0.662 2 3 10.9 11.1 2 1621 251 256 2.646 -0.018 0.647 0.258 2 2 13.0 8.0 2 1621 239b 257 3.276 -0.018 0.884 0.570 1 2 10.8 6.8 2 1621 244 258 2.595 -0.018 0.639 0.939 2 4 12.7 8.1 2 1621 239 259 3.701 -0.018 0.000 0.000 1 1 12.1 6.0 2 1621 252a 260 3.344 -0.018 0.646 0.662 2 3 11.0 6.7 2 1622 242 261 3.344 -0.018 0.709 1.266 1 5 10.8 6.7 2 1622 243 262 3.423 -0.018 0.906 1.000 1 3 12.8 6.5 2 1622 249 263 3.608 -0.018 0.741 0.393 1 2 11.1 6.2 2 1622 245 264 4.624 -0.018 0.778 1.358 1 5 12.3 4.3 5 1623 238 265 3.416 -0.018 0.854 1.228 1 4 12.4 6.6 2 1624 241 266 6.886 -0.018 0.498 1.095 1 6 11.2 0.0 5 1626 D1142 267 5.196 -0.018 0.933 0.624 0 2 14.1 3.2 5 1630 253 268 2.826 -0.018 0.000 0.000 0 1 9.5 7.7 2 1631 9-20-87-1 269 3.965 0.725 1.001 0.694 0 2 13.5 5.5 3 1631 8-11-87-1 270 3.965 1.000 0.000 0.000 0 1 10.7 5.5 3 1631 9-20-87-2 271 5.164 -0.018 0.552 1.971 2 13 11.7 3.3 5 1635 021701.01 272 3.065 -0.018 0.619 1.718 1 9 12.7 7.2 2 1637 111800.01a 273 1.826 -0.018 0.642 1.955 2 11 12.2 9.6 2 1637 111800.01b 274 2.668 -0.018 0.749 1.097 1 4 12.7 8.0 2 1638 111800.01c 275 1.678 2.904 0.643 1.755 2 9 11.6 4.9 2 1644 D1143 276 0.469 2.552 0.766 1.343 1 5 11.6 8.2 3 1647 240 277 0.931 0.692 0.738 1.488 1 6 10.8 6.9 2 1648 239a 278 3.455 2.319 0.678 0.305 1 2 12.5 0.0 7 1648 D1154 279 1.578 1.396 0.727 1.290 2 5 12.8 5.2 5 1649 B6527 280Appendix E (Continued) E-8

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DC2 DC1 ET HT SE ST Temp(C) Depth (m) Community Level (m) Locality No. 1.613 4.417 0.688 2.191 2 13 12.1 5.1 2 1649 D1144 281 1.737 1.514 0.882 0.973 2 3 11.3 4.7 5 1649 223 282 0.719 0.968 0.877 0.967 2 3 10.2 7.5 2 1649 238a 283 0.095 2.262 0.961 1.346 1 4 10.4 9.2 3 1655 218 284 1.651 3.284 0.686 1.233 2 5 11.1 5.0 2 1655 D1124 285 1.157 4.126 0.685 1.568 1 7 10.5 6.3 2 1674 D1155 286 1.716 2.271 0.996 0.689 1 2 11.7 4.8 5 1674 229 287 0.666 1.974 0.000 0.000 0 1 9.5 7.7 3 1675 226 288 1.428 5.727 0.740 1.490 2 6 10.8 5.6 3 1676 D1145 289 0.253 2.332 0.965 1.063 1 3 10.2 8.8 3 1677 225 290 1.572 3.329 0.984 0.677 1 2 12.2 5.2 2 1679 D1146 291 1.270 2.878 0.977 1.075 1 3 11.3 6.0 2 1689 D1125 292 0.000 1.653 0.954 1.051 1 3 10.4 9.5 3 1689 227 293 0.000 1.653 0.954 1.051 1 3 10.4 9.5 3 1690 219 294 1.778 0.000 0.000 0.000 1 1 10.3 4.6 4 1693 221 295 2.738 -0.050 0.926 1.309 1 4 12.0 9.0 1 1696 206 296 1.975 -0.050 0.000 0.000 1 1 10.7 10.1 4 1696 208 297 1.975 -0.050 0.000 0.000 1 1 10.7 10.1 4 1696 209 298 1.975 -0.050 0.000 0.000 1 1 10.7 10.1 4 1696 210 299 1.975 -0.050 0.000 0.000 1 1 10.7 10.1 4 1696 211 300 2.068 -0.050 0.902 0.995 1 3 14.1 10.0 4 1696 212 301 2.612 -0.050 0.901 1.687 1 6 12.4 9.2 1 1696 213 302 2.457 -0.050 0.916 1.992 2 8 12.6 9.4 1 1696 214 303 2.689 -0.050 0.827 1.602 1 6 13.3 9.1 1 1696 215 304 2.863 -0.050 0.927 1.310 1 4 13.5 8.8 1 1696 216 305 5.382 1.000 1.001 0.694 1 2 16.3 5.2 5 1696 1-20-89-3 306 4.010 -0.050 0.626 0.224 0 2 9.8 7.2 2 1697 053002.03 307 2.308 -0.050 0.772 1.687 2 7 11.8 9.6 1 1703 203 308 1.625 -0.050 0.829 0.911 1 3 16.3 10.6 4 1705 060701.01 309 2.004 -0.050 0.000 0.000 0 1 15.5 10.1 4 1707 185 310 3.085 -0.050 0.921 1.710 0 6 12.9 8.5 1 1708 183 311 3.055 -0.050 0.962 0.654 1 2 10.1 8.6 1 1712 204 312 5.831 -0.050 0.677 0.709 0 3 12.7 4.5 2 1721 194 313 2.231 -0.050 0.954 1.051 0 3 14.3 9.8 1 1722 197 314 3.960 -0.050 0.864 1.240 0 4 12.5 7.2 2 1722 202 315Appendix E (Continued) E-9

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DC2 DC1 ET HT SE ST Temp(C) Depth (m) Community Level (m) Locality No. 1.974 -0.050 0.753 0.410 1 2 15.4 10.1 4 1725 201 316 2.445 -0.050 0.996 1.095 0 3 12.7 9.4 1 1726 198 317 3.077 -0.050 0.588 0.856 1 4 13.4 8.5 1 1745 111700.01 318 3.007 -0.050 0.613 1.303 2 6 10.7 8.6 1 1771 D1193 319 8.949 -0.050 0.000 0.000 0 1 10.5 0.0 7 1780 177 320 2.936 -0.050 0.651 1.363 3 6 11.9 8.7 1 1785 051599.01 321 2.672 -0.050 0.000 0.000 0 1 11.5 9.1 1 1786 D1087 322 2.988 -0.050 0.723 1.285 1 5 11.2 8.7 1 1789 175 323 8.162 -0.050 0.958 1.056 1 3 12.5 1.1 7 1804 178 324 3.306 -0.050 0.866 0.549 0 2 10.2 8.2 1 1809 D1187 325 3.232 -0.050 0.713 0.760 0 3 10.4 8.3 1 1813 D1194 326 5.382 0.949 1.002 1.388 0 4 13.3 5.2 5 1830 2092 27 1.367 -0.050 0.798 1.161 0 4 12.9 11.0 4 1830 171 328 0.000 -0.050 0.000 0.000 0 1 13.5 13.0 2 1835 162 329 1.613 -0.050 0.873 0.963 0 3 13.8 10.7 4 1838 157 330 5.509 -0.050 0.969 0.662 0 2 11.7 5.0 2 1844 146 331 0.000 -0.050 0.000 0.000 0 1 3.5 13.0 2 1845 146a 332 3.539 -0.050 0.825 0.501 1 2 9.9 7.9 2 1845 192 333 3.184 -0.042 0.734 0.790 0 3 12.7 4.6 2 1848 163 334 1.836 -0.042 0.841 0.925 0 3 13.9 6.8 3 1858 170 335 0.201 -0.042 0.688 1.012 0 4 11.7 9.5 2 1863 172 336 1.011 -0.042 0.665 0.979 0 4 11.1 8.2 2 1866 155 337 2.580 -0.042 0.886 1.488 0 5 12.6 5.6 2 1869 101301.06 338 2.547 1.000 1.001 0.694 0 2 11.1 5.7 3 1869 D1188 339 2.020 -0.042 0.765 1.119 0 4 12.5 6.5 3 1869 156 340 2.935 -0.042 0.978 1.076 0 3 14.0 5.0 2 1873 149 341 2.935 -0.042 0.978 1.076 0 3 14.0 5.0 2 1875 150 342 2.333 -0.042 0.718 0.362 0 2 13.5 6.0 2 1876 161 343 2.780 -0.042 0.632 0.234 0 2 14.1 5.3 2 1878 158 344 3.216 -0.042 0.000 0.000 0 1 11.5 4.6 2 1881 148 345 2.935 -0.042 0.978 1.076 0 3 14.0 5.0 2 1882 148a 346 3.216 -0.042 0.000 0.000 0 1 11.5 4.6 2 1884 153 347 3.004 -0.042 0.934 1.318 0 4 13.4 4.9 2 1887 154 348 2.344 -0.042 0.998 0.691 0 2 15.2 6.0 2 1894 152 349 6.037 -0.042 0.587 0.566 1 3 11.2 0.0 7 1900 151 350Appendix E (Continued) E-10

PAGE 390

DC2 DC1 ET HT SE ST Temp(C) Depth (m) Community Level (m) Locality No. 3.128 -0.042 0.865 1.464 0 5 12.8 4.7 2 1902 145 351 3.497 -0.042 0.854 0.941 0 3 13.0 4.1 2 1923 165 352 -0.000 -0.042 0.560 0.518 0 3 11.7 9.8 2 1924 7-21-87-1 353 2.689 -0.042 0.000 0.000 0 1 16.8 5.4 2 1933 D1189 354 2.547 0.573 0.000 0.000 0 1 14.6 5.7 3 1943 D1190 355 0.928 -0.042 0.990 0.683 0 2 10.5 8.3 2 2055 D1184 356 2.362 -0.003 0.979 0.672 1 2 15.2 7.6 1 2098 052902.04 357 2.463 -0.003 0.717 2.065 2 11 13.6 7.5 1 2105 110702.09 358 4.195 1.000 0.000 0.000 0 1 11.5 5.8 3 2114 112 359 4.503 -0.003 0.568 1.226 1 6 11.1 5.5 3 2120 D1203 360 9.023 -0.003 0.980 0.673 0 2 10.5 1.0 7 2129 D1191 361 2.484 -0.003 0.999 0.692 0 2 15.2 7.5 1 2132 103a 362 2.386 -0.003 0.000 0.000 1 1 13.2 7.6 1 2136 119a 363 2.695 -0.003 0.690 1.708 1 8 13.5 7.3 1 2137 106 364 2.401 -0.003 0.782 0.853 1 3 13.9 7.6 1 2137 105a 365 2.658 -0.003 0.914 0.603 0 2 14.4 7.3 1 2138 77 366 3.072 -0.003 0.774 1.536 3 6 12.8 6.9 1 2138 79 367 2.598 -0.003 0.865 1.241 2 4 13.7 7.4 1 2138 74 368 3.297 -0.003 0.789 2.161 4 11 13.0 6.7 1 2138 81 369 3.201 -0.003 0.758 1.109 2 4 12.0 6.8 1 2138 80 370 3.156 -0.003 0.682 2.182 4 13 13.2 6.8 1 2138 71 371 2.924 -0.003 0.798 0.873 0 3 13.8 7.1 1 2138 103 372 2.256 -0.003 0.820 1.747 1 7 14.2 7.7 1 2138 107 373 2.362 -0.003 0.979 0.672 1 2 15.2 7.6 1 2138 86 374 1.948 -0.003 0.691 1.240 0 5 15.2 8.1 1 2138 108 375 1.871 -0.003 0.814 0.487 0 2 16.1 8.1 1 2138 93a 376 2.386 -0.003 0.000 0.000 1 1 13.2 7.6 1 2138 124 377 2.413 -0.003 0.912 1.006 2 3 13.8 7.6 1 2138 92 378 1.871 -0.003 0.814 0.487 0 2 16.1 8.1 1 2138 110 379 3.103 -0.003 0.836 1.430 1 5 13.5 6.9 1 2138 115 380 2.297 -0.003 0.707 0.752 1 3 13.7 7.7 1 2138 119 381 2.539 -0.003 0.894 0.581 1 2 13.5 7.5 1 2138 118 382 2.510 -0.003 0.878 1.949 3 8 14.0 7.5 1 2139 91 383 2.386 -0.003 0.000 0.000 1 1 13.2 7.6 1 2139 76 384 2.384 -0.003 0.923 1.712 1 6 15.0 7.6 1 2139 114 385Appendix E (Continued) E-11

PAGE 391

DC2 DC1 ET HT SE ST Temp(C) Depth (m) Community Level (m) Locality No. 2.347 -0.003 0.869 1.805 1 7 14.6 7.7 1 2139 73 386 2.362 -0.003 0.979 0.672 1 2 15.2 7.6 1 2139 83 387 3.525 -0.003 0.513 1.279 3 7 13.4 6.5 1 2140 B6539 388 2.227 -0.003 0.693 2.629 6 20 13.5 7.8 1 2142 102 389 2.362 -0.003 0.979 0.672 1 2 15.2 7.6 1 2142 109 390 2.463 -0.003 0.844 1.440 1 5 13.1 7.5 1 2144 117 391 2.371 -0.003 0.719 1.462 2 6 14.6 7.6 1 2144 130 392 2.735 -0.003 0.711 1.605 2 7 13.0 7.3 1 2144 104 393 2.083 -0.003 0.675 1.804 3 9 13.4 7.9 1 2145 101 394 2.464 -0.003 0.763 2.295 4 13 13.1 7.5 1 2145 87 395 2.484 -0.003 0.999 0.692 0 2 15.2 7.5 1 2145 113 396 3.061 -0.003 0.604 1.105 2 5 13.9 6.9 1 2144 D1196 397 2.454 -0.003 0.926 1.309 1 4 14.6 7.5 1 2147 85 398 2.342 -0.003 0.000 0.000 0 1 16.8 7.7 1 2147 84 399 2.231 -0.003 0.891 1.494 1 5 14.6 7.8 1 2147 102b 400 2.231 -0.003 0.841 1.213 2 4 13.4 7.8 1 2147 94 401 2.561 -0.003 0.845 1.777 2 7 14.1 7.4 1 2148 98 402 2.451 -0.003 0.993 1.092 1 3 14.5 7.5 1 2148 97 403 2.386 -0.003 0.000 0.000 1 1 13.2 7.6 1 2149 82 404 5.470 -0.003 0.000 0.000 0 1 10.1 4.5 3 2149 B6538 405 2.369 -0.003 0.980 0.673 0 2 15.6 7.6 1 2150 116 406 2.339 -0.003 0.798 1.566 2 6 13.4 7.7 1 2152 93 407 2.225 -0.003 0.708 2.053 4 11 14.2 7.8 1 2152 102a 408 5.327 -0.003 0.540 1.687 1 10 12.9 4.7 1 2152 B6537 409 1.944 -0.003 0.769 1.683 1 7 13.5 8.1 1 2154 105 410 3.061 -0.003 0.836 0.919 1 3 15.3 6.9 1 2154 140a 411 3.423 -0.003 0.758 0.416 1 2 14.3 6.6 1 2154 140b 412 2.454 -0.003 0.926 1.533 2 5 13.8 7.5 1 2155 99 413 2.530 -0.003 0.866 0.955 2 3 12.8 7.5 1 2156 89 414 2.471 -0.003 0.950 1.047 1 3 13.5 7.5 1 2162 114a 415 2.695 -0.003 0.691 1.576 3 7 12.3 7.3 1 2163 140 416 0.000 -0.003 0.000 0.000 1 1 11.0 10.0 2 2164 78 417 2.002 -0.003 0.631 1.149 2 5 14.4 8.0 1 2166 111 418 9.692 -0.003 0.000 0.000 0 1 9.5 0.3 7 2174 139 419 2.693 -0.003 0.674 2.170 3 13 12.6 7.3 1 2174 75 420Appendix E (Continued) E-12

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DC2 DC1 ET HT SE ST Temp(C) Depth (m) Community Level (m) Locality No. 2.820 -0.003 0.759 1.804 2 8 12.9 7.2 1 2175 120 421 3.717 -0.003 0.944 0.636 0 2 13.8 6.3 1 2180 138 422 1.172 1.154 0.960 1.345 1 4 14.8 7.1 2 2186 130b 423 3.784 1.288 0.851 0.937 0 3 13.2 1.0 4 2188 132 424 0.000 0.204 0.000 0.000 1 1 13.2 9.8 1 2190 72 425 1.172 1.154 0.960 1.345 1 4 14.8 7.1 2 2191 130a 426 2.648 1.758 0.947 1.737 1 6 13.7 3.6 2 2194 102c 427 1.182 1.711 0.848 1.221 0 4 14.6 7.0 2 2194 123 428 1.498 1.823 0.991 1.090 0 3 14.3 6.3 2 2194 127 429 2.664 1.925 0.933 1.029 0 3 14.8 3.6 4 2197 121 430 1.172 1.154 0.960 1.345 1 4 14.8 7.1 4 2200 130c 431 4.195 -0.000 0.825 0.501 2 2 11.4 0.0 5 2212 135 432 2.718 4.280 0.816 1.876 2 8 13.9 3.4 3 2237 D1197 433 2.555 1.816 0.947 1.737 1 6 14.2 3.8 4 2239 100 434 3.390 1.422 0.857 1.638 2 6 13.5 1.9 4 2240 128 435 2.651 4.004 0.831 2.012 2 9 13.4 3.6 3 2243 D1198 436 2.694 9.236 0.914 2.308 2 11 11.7 3.5 5 2249 D1201 437 0.209 0.979 0.781 1.544 1 6 12.2 10.9 1 2250 60 438 3.803 1.138 0.502 0.41 2 3 12.9 0.0 7 2251 59 439 0.965 0.786 0.808 0.885 3 3 11.2 8.6 1 2255 57a 440 1.561 3.736 0.604 0.882 0 4 14.3 6.8 1 2255 D1200 441 0.462 0.886 0.887 1.266 2 4 12.1 10.1 1 2258 67 442 0.403 1.356 0.755 1.105 0 4 13.5 10.3 1 2262 64 443 0.767 0.000 0.631 1.938 2 11 11.9 9.2 2 2269 58 444 0.000 1.106 0.798 1.972 2 9 13.9 11.5 1 2275 66 445 1.265 4.512 0.944 0.636 0 2 13.3 7.7 1 2277 B6540 446 0.637 0.988 0.808 0.885 0 3 12.9 9.6 1 2281 63 447 1.697 0.478 0.623 1.136 0 5 13.1 6.4 2 2283 110702.10 448 0.569 1.114 0.819 1.592 2 6 12.0 9.8 1 2286 62 449 0.523 1.496 0.860 1.236 0 4 11.9 9.9 1 2286 64a 450 0.741 1.486 0.912 1.007 3 3 11.6 9.3 1 2295 65 451 0.577 0.855 0.935 1.319 1 4 12.3 9.8 1 2302 57 452 0.822 3.212 0.608 1.582 1 8 10.9 9.0 1 2304 D1185 453 0.293 0.805 0.811 1.736 2 7 13.7 10.6 1 2305 68 454 1.186 6.842 0.793 1.154 1 4 11.4 7.9 1 2305 D1192 455Appendix E (Continued) E-13

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DC2 DC1 ET HT SE ST Temp(C) Depth (m) Community Level (m) Locality No. 1.967 1.690 0.620 0.215 0 2 13.0 5.6 3 2306 61 456 1.121 0.000 0.000 0.000 0 1 10.0 1.5 6 2308 48 457 1.709 2.131 0.869 0.958 0 3 14.1 1.3 5 2308 55 458 1.121 0.000 0.000 0.000 0 1 10.0 1.5 6 2339 50 459 1.121 0.000 0.000 0.000 0 1 10.0 1.5 6 2346 54 460 1.121 0.000 0.000 0.000 0 1 10.0 1.5 6 2351 53 461 1.121 0.000 0.000 0.000 0 1 10.0 1.5 6 2360 52 462 1.121 0.000 0.000 0.000 0 1 10.0 1.5 6 2374 51 463 3.919 1.513 0.000 0.000 0 1 10.0 0.3 7 2394 47 464 1.121 0.000 0.000 0.000 0 1 10.0 1.5 6 2395 37 465 1.121 0.000 0.000 0.000 0 1 10.0 1.5 6 2420 29 466 4.625 1.120 0.729 0.377 0 2 16.8 0.0 7 2420 2376 467 2.892 1.707 0.957 1.055 2 3 10.5 0.7 7 2420 32 468 1.194 1.886 0.857 1.637 4 6 11.6 1.5 5 2422 41 469 1.121 0.000 0.000 0.000 0 1 17.2 1.5 6 2423 38 470 3.333 1.622 0.962 1.060 2 3 10.0 0.6 7 2423 31 471 1.121 0.000 0.000 0.000 0 1 10.0 1.5 6 2424 33 472 2.000 6.861 0.944 1.041 0 3 10.8 1.1 7 2425 D2089 473 3.281 1.673 0.913 1.518 2 5 11.7 0.6 7 2426 30 474 2.084 2.361 0.901 2.198 5 10 11.6 1.1 5 2427 40 475 1.847 2.945 0.000 0.000 0 1 10.0 1.2 5 2428 36 476 0.560 1.338 0.969 0.662 1 2 13.9 1.8 6 2428 39 477 1.746 3.919 0.745 1.652 1 7 11.2 1.2 6 2428 061001.01 478 2.206 2.217 0.922 1.998 3 8 11.7 1.0 5 2429 35 479 1.087 2.201 0.999 0.692 2 2 10.1 1.5 5 2429 42 480 1.829 1.794 0.920 1.863 3 7 12.4 1.2 5 2429 43 481 0.000 2.677 0.000 0.000 1 1 10.0 2.0 6 2429 44 482 0.000 2.677 0.000 0.000 1 1 10.0 2.0 6 2429 45 483 1.121 0.000 0.000 0.000 0 1 10.0 1.5 6 2429 46 484 DC1: DCAaxis 1score. Level :Correlatedstratigraphic levelabovethe baseoftheEtchegoinGroup. Notes: DC2: DCAaxis 2score. ST:Species richness ofthetotalfaunainthestratigraphic sampleinterval. SE:Species richness ofendemic species in thestratigraphic sampleinterval. HT:Totalfaunadiversity of thestratigraphicsample interval. ET:Totalfaunaeveness inthestratigraphic sampleinterval. Appendix E (Continued) E-14

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Appendix F

PAGE 395

ET HGp HFm H3O H4O HE HT nE NOE SE nT NOT ST Level (m) No. 0.91 4.23 4.21 4.27 4.21 2.18 3.47 3 15 10 3 50 35 10 1 0.90 4.23 4.21 4.27 4.21 1.98 3.48 4 12 8 5 57 36 20 2 0.94 4.23 4.21 4.27 4.21 2.02 3.20 4 12 8 4 37 26 30 3 0.90 4.23 4.21 4.27 4.21 2.18 3.50 4 15 10 5 48 37 50 4 4.23 4.21 4.27 4.21 0.00 70 5 4.23 4.21 4.27 4.21 0.00 200 6 1.00 4.23 4.21 4.27 4.21 0.00 1.79 1 1 1 1 6 6 220 7 1.00 4.23 4.21 4.27 4.21 0.00 2.08 1 1 1 2 8 8 230 8 1.00 4.23 4.21 4.27 4.21 0.00 1.79 0 0 0 1 6 6 270 9 1.00 4.23 4.21 4.27 4.21 1.10 2.40 1 3 3 1 11 11 320 10 4.23 4.21 4.27 4.21 0.00 340 11 4.23 4.21 4.27 4.21 0.00 380 12 1.00 4.23 4.21 4.27 4.21 0.00 1.39 1 1 1 1 4 4 400 13 0.94 4.23 4.21 4.27 4.21 1.04 2.02 2 4 3 2 11 8 440 14 4.23 4.21 4.27 4.21 0.00 460 15 4.23 4.21 4.27 4.21 0.00 530 16 0.94 4.23 4.21 4.27 4.21 0.00 0.64 1 1 1 2 3 2 550 17 1.00 4.23 4.21 4.27 4.21 1.10 1.79 1 3 3 2 6 6 620 18 1.00 4.23 4.12 4.27 4.07 0.00 0.00 0 0 0 1 1 1 660 19 1.00 4.23 4.12 4.27 4.07 1.39 1.95 1 4 4 1 7 7 700 20 1.00 4.23 4.12 4.27 4.07 0.69 2.20 1 2 2 1 9 9 730 21 4.23 4.12 4.27 4.07 0.00 750 22 4.23 4.12 4.27 4.07 0.00 780 23 1.00 4.23 4.12 4.27 4.07 0.00 0.00 0 0 0 1 1 1 800 24 1.00 4.23 4.12 4.27 4.07 0.00 0.69 1 1 1 1 2 2 850 25 1.00 4.23 4.12 4.27 4.07 0.00 1.39 1 1 1 1 4 4 920 26 1.00 4.23 4.12 4.27 4.07 0.69 1.10 1 2 2 1 3 3 930 27 0.85 4.23 4.12 4.27 4.07 2.17 3.24 8 16 10 9 56 30 940 28 1.00 4.23 4.12 4.27 4.07 0.00 0.69 1 1 1 1 2 2 960 29 1.00 4.23 4.12 4.27 4.07 0.00 0.69 1 1 1 1 2 2 970 30 1.00 4.23 4.12 4.27 4.07 0.69 1.10 1 2 2 1 3 3 1000 31 0.97 4.23 4.12 4.27 4.07 1.75 2.91 1 7 6 4 21 19 1010 32 1.00 4.23 4.12 4.27 4.07 1.61 2.71 1 5 5 1 15 15 1020 33 1.00 4.23 4.12 4.27 4.07 0.00 2.08 0 0 0 1 8 8 1030 34 1.00 4.23 4.12 4.27 4.07 1.79 3.05 2 6 6 3 21 21 1050 35 1.00 4.23 4.12 4.27 4.07 0.69 1.95 1 2 2 1 7 7 1070 36 0.91 4.23 4.12 4.27 4.07 1.91 3.00 2 8 7 3 29 22 1100 37 0.97 4.23 4.12 4.27 4.07 1.33 2.27 3 5 4 3 11 10 1110 38 1.00 4.23 4.12 4.27 4.07 0.69 2.40 1 2 2 1 11 11 1120 39 1.00 4.23 4.12 4.27 4.07 1.95 2.83 2 7 7 2 17 17 1130 40 1.00 4.23 4.12 4.27 4.07 0.00 0.69 1 1 1 1 2 2 1140 41Appendix F F-1

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E T H Gp H Fm H 3O H 4O H E H T n E N OE S E n T N OT S T Level (m) No. 1.00 4.23 4.12 4.27 4.07 1.10 2.08 1 3 3 1 8 8 1170 42 0.88 4.23 4.12 4.27 4.07 1.89 2.81 5 13 8 6 27 19 1180 43 0.90 4.23 4.12 4.27 4.07 2.03 3.23 5 10 8 5 38 28 1190 44 0.97 4.23 4.12 4.27 4.07 0.00 2.46 2 2 1 2 13 12 1210 45 0.98 4.23 4.12 4.27 4.07 1.33 2.69 2 5 4 2 16 15 1220 46 0.79 4.23 4.12 4.27 4.07 0.00 1.15 4 4 1 4 7 4 1240 47 1.00 4.23 4.12 4.12 2.95 0.00 0.00 1 1 1 1 1 1 1280 48 1.00 4.23 4.12 4.12 2.95 0.00 0.00 0 0 0 1 2 2 1330 49 1.00 4.23 4.12 4.12 2.95 0.00 0.69 0 0 0 1 2 2 1390 50 1.00 4.23 4.12 4.12 2.95 0.00 1.10 0 0 0 1 3 3 1400 51 0.87 4.23 4.12 4.12 2.95 1.04 2.50 4 4 3 6 22 14 1440 52 1.00 4.23 4.12 4.12 2.95 0.00 1.10 1 1 1 1 3 3 1450 53 0.96 4.23 4.12 4.12 2.95 1.04 2.04 2 4 3 3 9 8 1460 54 0.96 4.23 4.12 4.12 3.61 0.00 2.04 1 1 1 2 9 8 1480 55 0.86 4.23 4.12 4.12 3.61 0.00 0.95 3 3 1 3 5 3 1490 56 1.00 4.23 4.12 4.12 3.61 1.39 2.08 1 4 4 1 8 8 1500 57 0.95 4.23 4.12 4.12 3.61 1.33 2.84 3 5 4 3 22 18 1510 58 0.84 4.23 4.12 4.12 3.61 1.85 2.59 6 11 7 8 28 16 1520 59 0.91 4.23 4.12 4.12 3.61 1.75 2.21 2 7 6 3 13 10 1530 60 0.82 4.23 4.12 4.12 3.61 2.18 3.54 8 20 11 10 70 42 1540 61 0.81 4.23 4.12 4.12 3.35 1.98 3.20 16 24 9 22 68 30 1550 62 0.87 4.23 4.12 4.12 3.35 1.91 3.32 2 8 7 4 45 32 1560 63 0.69 4.23 4.12 4.12 3.94 2.44 3.53 7 30 15 12 117 50 1570 64 0.73 4.23 4.12 4.12 3.94 2.28 3.56 15 36 15 19 121 48 1580 65 0.70 4.23 4.12 4.12 3.94 2.04 3.80 19 38 10 23 164 64 1590 66 0.75 4.23 4.12 4.12 3.94 2.09 3.56 14 27 11 19 91 47 1600 67 0.71 4.23 4.12 4.12 3.94 1.04 3.18 11 16 5 12 67 34 1610 68 0.74 4.23 4.12 4.12 3.94 0.76 3.13 11 14 4 12 64 31 1620 69 0.66 4.23 4.12 4.12 3.17 0.82 2.54 12 16 4 13 42 19 1630 70 0.88 4.23 4.12 4.12 3.17 0.87 3.17 4 6 3 7 41 27 1640 71 0.83 4.23 4.12 4.12 3.19 0.99 3.18 8 11 3 8 46 29 1650 72 0.96 4.23 4.12 4.12 3.19 1.10 2.04 2 3 3 2 9 8 1660 73 0.87 4.23 4.12 4.12 3.19 1.33 2.43 5 6 4 6 21 13 1680 74 0.91 4.23 4.12 4.12 3.19 1.04 1.70 3 4 3 3 10 6 1690 75 0.78 4.23 3.56 3.10 3.13 0.92 2.32 11 12 3 12 39 13 1700 76 0.92 4.23 3.56 3.10 3.13 1.10 2.48 2 3 3 4 17 13 1710 77 1.00 4.23 3.56 3.10 3.13 0.00 0.69 1 1 1 1 2 2 1720 78 0.93 4.23 3.56 3.10 3.13 0.69 2.12 1 2 2 6 17 9 1730 79 1.00 4.23 3.56 3.10 3.13 0.00 1.39 1 1 1 1 8 4 1750 80 1.00 4.23 3.56 3.10 3.13 0.69 1.95 1 2 2 2 7 7 1780 81 0.95 4.23 3.56 3.10 3.13 1.04 2.25 2 4 3 3 12 10 1790 82Appendix F (Continued) F-2

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ET HGp HFm H3O H4O HE HT nE NOE SE nT NOT ST Level (m) No. 1.00 4.23 3.56 3.10 3.13 0.00 1.61 1 1 1 2 5 5 1810 83 1.00 4.23 3.56 3.10 3.13 0.00 1.10 0 0 0 1 6 3 1820 84 1.00 4.23 3.56 3.10 3.13 0.00 2.08 0 0 0 2 8 8 1830 85 0.94 4.23 3.56 3.10 3.13 0.00 1.04 0 0 0 2 4 4 1840 86 0.94 4.23 3.56 3.10 2.48 0.00 1.73 1 1 1 4 8 6 1850 87 1.00 4.23 3.56 3.10 2.48 0.00 1.10 0 0 0 1 3 3 1860 88 0.86 4.23 3.56 3.10 2.48 0.00 2.33 1 1 1 5 19 12 1870 89 0.87 4.23 3.56 3.10 2.48 0.00 1.47 0 0 0 4 10 5 1880 90 0.98 4.23 3.56 3.10 2.48 0.00 1.37 0 0 0 4 9 4 1890 91 1.00 4.23 3.56 3.10 2.48 0.00 1.61 1 1 1 2 5 5 1900 92 1.00 4.23 3.56 3.10 2.48 0.00 1.61 0 0 0 1 5 5 1910 93 1.00 4.23 3.56 3.10 2.48 0.00 1.79 0 0 0 2 6 6 1930 94 1.00 4.23 3.56 3.10 2.48 0.00 0.00 0 0 0 1 1 1 1940 95 1.00 4.23 3.56 3.10 2.48 0.00 0.00 0 0 0 1 1 1 1950 96 4.23 3.56 3.10 2.48 0.00 0.00 1970 97 4.23 3.56 3.10 2.48 0.00 0.00 2040 98 1.00 4.23 3.56 3.10 2.48 0.00 0.69 0 0 1 1 2 2 2060 99 1.00 4.23 3.56 3.54 3.31 0.00 0.69 1 1 1 1 2 2 2100 100 1.00 4.23 3.56 3.54 3.31 0.69 2.40 1 2 2 1 11 11 2110 101 1.00 4.23 3.56 3.54 3.31 0.00 1.95 1 1 1 1 7 7 2120 102 1.00 4.23 3.56 3.54 3.31 0.00 0.69 0 0 0 1 2 2 2130 103 0.57 4.23 3.56 3.54 3.31 1.43 2.93 21 33 8 27 120 32 2140 104 0.71 4.23 3.56 3.54 3.31 1.59 3.02 14 26 7 18 97 29 2150 105 0.80 4.23 3.56 3.54 3.31 1.48 3.08 8 13 6 8 47 27 2160 106 0.94 4.23 3.56 3.54 3.31 1.55 2.43 4 7 5 4 16 12 2170 107 0.92 4.23 3.56 3.54 3.31 1.39 2.81 2 4 4 4 24 18 2180 108 0.94 4.23 3.56 3.54 3.06 0.00 1.73 2 2 1 3 8 6 2190 109 0.80 4.23 3.56 3.54 3.06 0.00 2.08 3 2 0 6 24 10 2200 110 1.00 4.23 3.56 3.54 3.06 0.00 0.69 1 0 1 1 2 2 2220 111 0.91 4.23 3.56 3.54 3.06 0.00 2.54 1 1 3 3 22 14 2240 112 0.98 4.23 3.56 3.54 3.06 1.04 2.93 3 4 0 3 20 19 2250 113 0.83 4.23 3.56 3.54 3.07 1.49 2.65 3 8 5 4 27 17 2260 114 0.96 4.23 3.56 3.54 3.07 0.00 1.91 1 1 1 2 8 7 2270 115 0.96 4.23 3.56 3.54 3.07 0.69 1.75 1 2 2 2 7 6 2280 116 0.88 4.23 3.56 3.54 3.07 0.69 2.07 1 2 2 4 20 9 2290 117 1.00 4.23 3.56 3.54 3.07 1.10 1.95 1 3 3 1 7 7 2300 118 0.83 4.23 3.56 3.54 3.07 1.04 2.70 4 4 3 7 27 18 2310 119 1.00 4.23 3.56 3.54 2.58 0.00 0.00 0 0 0 1 1 1 2340 120 1.00 4.23 3.56 3.54 2.58 0.00 0.00 0 0 0 1 1 1 2350 121 1.00 4.23 3.56 3.54 2.58 0.00 0.00 0 0 0 2 2 1 2360 122 1.00 4.23 3.56 3.54 2.58 0.00 0.00 0 0 0 1 1 1 2380 123Appendix F (Continued) F-3

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ET HGp HFm H3O H4O HE HT nE NOE SE nT NOT ST Level (m) No. 1.00 4.23 3.56 3.54 2.58 0.00 0.69 0 0 0 2 2 2 2400 124 1.00 4.23 3.56 3.54 2.58 0.69 1.79 1 2 2 3 6 6 2420 125 0.81 4.23 3.56 3.54 2.58 1.47 2.62 11 25 5 16 59 17 2430 126 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0 0 0 0 0 2440 127 0.93 4.23 3.91 3.86 3.47 0.74 1.79 3 6 3 4 21 13 Average Level :Assigned stratigraphic level above the base of the Etchegoin Gro up. Notes: ST: Species richness of the total fauna in the stratigraphic sample interva l. NT: Occurrences of all species in the stratigraphic sample interval. nT: Number of locality collections in the total fauna sample interval. SE: Species richness of endemic species in the stratigraphic sample inter val. NE: Occurrences of endemic species in the stratigraphic sample interval nE: Number of locality collections in th eendemic fauna sample interval. HT:Total fauna diversity of the stratigraphic sample interval. HE: Endemic species diversity of the stratigraphic sample interval.. H4O:Total fauna diversity in 4th-order eucstaic cycles. H3O:Total fauna diversity in 3rd-order eucstaic cycles. HFm:Total fauna diversity of each Etchegoin Group formation. HGp:Total fauna diversity of the Etchegoin Group. ET:Total fauna eveness in the stratigraphic sample interval. Appendix F (Continued) F-4

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384 Appendix G

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Appendix G 385 Nevada Isotope Geochronology Laboratory Descripti on and Procedures Samples analyzed by the 40Ar/39Ar method at the University of Nevada Las Vegas were wrapped in Al foil and stacked in 6 mm inside diameter Pyrex tubes. Individual packets averaged 3 mm thick and neutron fluence mon itors (FC-2, Fish Canyon Tuff sanidine) were placed every 5-10 mm along the tube. Synthetic K-glass and optical grade CaF2 were included in the irradiation packages to monit or neutron induced argon interferences from K and Ca. Loaded tubes were pac ked in an Al container for irradiation. Samples irradiated at the Nuclear Sci ence Center at Texas A&M University were in-core for 14 hours in the D3 position on the core edge (fuel rods on three sides, moderator on the fourth side) of the 1MW TRIGA type reactor. Irradiations are performed in a dry tube device, shielded against th ermal neutrons by a 5 mm thick jacket of B4C powder, which rotates about its axis at a rate of 0.7 revolutions per minute to mitigate horizontal flux gradients. Correction fac tors for interfering neutron reactions on K and Ca were determined by repeated analysis of Kglass and CaF2 fragments. Measured (40Ar/39Ar)K values were 0.00 ( 0.0002). Ca correction factors were (36Ar/37Ar)Ca = 2.82 ( 1.51) x 10-4 and (39Ar/37Ar)Ca = 6.77 ( 0.81) x 10-4. J factors were determined by fusion of 3-5 individual crystal s of neutron fluence monitors which gave reproducibilitys of 0.07% to 0.40% at each st andard position. Variation in neutron flux along the 100 mm length of the irradiation tub es was <4%. An error in J of 0.5% was used in age calculations. No significant neutr on flux gradients were present within individual packets of crystals as indicated by the excellent reproducibility of the single crystal flux monitor fusions. Irradiated crystals together with CaF2 and K-glass fragments were placed in a Cu sample tray in an high vacuum extraction line and w ere fused using a 20 W CO2 laser. Sample viewing during laser fusion was by a video camera system and positioning was via a motorized sample stage. Samples analyzed by the furnace step heating method utilized a double vacuum resistance furnace similar to the Staudacher et al. (1978) design. Reactive gases were removed by a single MA P and two GP-50 SAES getters prior to being admitted to a MAP 215-50 mass spectr ometer by expansion. The relative volumes of the extraction line and mass spectromete r allow 80% of the gas to be admitted to the mass spectrometer for laser fusion analyses and 76% for furnace heating analyses. Peak intensities were measured using a B alzers electron multiplier by peak hopping through 7 cycles; initial peak heights were determined by linear regression to the time of gas admission. Mass spectrometer discrimin ation and sensitivity was monitored by repeated analysis of atmospheric argon aliquots from an on-line pipette system. Measured 40Ar/36Ar ratios were 290.98 0.15 % during this work, thus a discrimination correction of 1.01553 (4 AMU) was applied to measur ed isotope ratios. The sensitivity of the mass spectrometer was ~6 x 10-17 mol mV-1 with the multiplier operated at a gain of 52 over the Faraday. Line blanks averaged 2.09 mV for mass 40 and 0.01 mV for mass 36 for laser fusion analyses and 10.34 mV for mass 40 and 0.04 mV for mass 36 for furnace heating analyses. Discrimination, sensitiv ity, and blanks were relatively constant over the period of data collection. Computer autom ated operation of the sample stage,

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Appendix G (Continued) 386 laser, extraction line and mass spectrometer as wel l as final data reduction and age calculations were done using LabSPEC software writt en by B. Idleman (Lehigh University). An age of 27.9 Ma (Steven et al., 196 7; Cebula et al., 1986) was used for the Fish Canyon Tuff sanidine flux monitor in calcu lating ages for samples. For 40Ar/39Ar analyses a plateau segment consists of 3 or more contiguous gas fractions having analytically indistinguishable age s (i.e. all plateau steps overlap in age at 2 s analytical error) and comprising a significant por tion of the total gas released (typically >50%). Total gas (integrated) ages are calculated by weighting by the amount of 39Ar released, whereas plateau ages are weighted by t he inverse of the variance. For each sample inverse isochron diagrams are examined to check for the effects of excess argon. Reliable isochrons are based on the MSWD cr iteria of Wendt and Carl (1991) and, as for plateaus, must comprise contiguous step s and a significant fraction of the total gas released. All analytical data are reported at the confidence level of 1 s (standard deviation).Cebula, G.T., M.J. Kunk, H.H. Mehnert, C.W. Naeser, J.D. Obradovich, and J.F. Sutter, The Fish Canyon Tuff, a potential standard for the 40Ar-39Ar and fission-track dating methods (abstract), Terra Cognita (6th Int. Conf. on Geochronology, Cosmochro nology and Isotope Geology), 6 139, 1986. Staudacher, T.H., Jessberger, E.K., Dorflinger, D., and Kiko, J., A refined ultrahigh-vacuum furnace f or rare gas analysis, J. Phys. E: Sci. Instrum ., 11 781-784, 1978. Steven, T.A., H.H. Mehnert, and J.D. Obradovich, Ag e of volcanic activity in the San Juan Mountains, Colorado, U.S. Geol. Surv. Prof. Pap., 575-D 47-55, 1967. Wendt, I., and Carl, C., 1991, The statistical dist ribution of the mean squared weighted deviation, Chemical Geology v. 86, p. 275-285.

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Appendix G (Continued) 387Nevada Isotope Geochronology Laboratory Sample Descriptions General Comments Isochrons are the most desirable treatment of 40 Ar/ 39 Ar data. This is because the isochron actually defines the isotopic composition of the initial argon in the sample (non-radiogenic argon). Ages calcula ted for an age spectrum are referred to as "apparent ages" because they are cal culated assuming the initial argon is atmospheric in composition thus, if ther e is excess argon ( 40 Ar/ 36 Ar > 295.5) the age will be overestimated. Isochrons have their measure of reliability, known as the mean square of weighted deviates (MSWD ) which is a statistical goodness of fit parameter. If it is greater than a certain value (which changes depending on the number of points, see Wendt and Carl, 1991, the sta tistical distribution of the mean squared weighted deviation, Chem. Geol., v. 86, p. 275-285) then there is more scatter than can be explained by analytical errors and it i s not a statistically valid isochron. If we provide an isochron it means that the statistical t est is valid, if not then no valid isochron was obtained. Also, there are issues of number of data points defining the isochron the more the better. Four points should be considered a bare minimum for statistical reasons, three points is getting to be a real concern. This can be understood simply by considering two points a perfectly fit straight line can be p ut through any two points, so completely accidental data can have a perfect line fit. It fo llows that with three points there is less of a chance of an accidental line fit, but it is still a very real possibility (especially if analytical errors are fairly large), this possibili ty gets exponentially smaller as the number of points defining the line (isochron) goes up, thus more points = a more reliable isochron. If there is no isochron, then a plateau age is next in preference. This is because a sample that gives ages which are analytically indis tinguishable from step to step is exhibiting what is known as "ideal" behavior, which suggests it has a simple geologic history, e.g., rapid cooling as a basalt lava, foll owed by no reheating or alteration, both of which may produce disturbed (discordant) age spectr a. A reliable plateau is 3 or more consecutive steps which are indistinguishable in ag e at the 2 sigma level and comprise >50% of the total 39Ar released. The lack of an isochron or a plateau does not mean the sample provides no useful information, but their pr esence gives greater confidence in the ages obtained and requires less subjective interpre tation. Of course, you must consider that we run samples su ch as this "blind" in that we do not know the geologic relations of the samples, either when we analyze them, or when we provide these general interpretations. The geol ogic constraints must always be considered when interpreting isotopic ages; if any discrepancies arise feel free to discuss them with us, as it can in some cases make a differ ence in how age data are interpreted. All analytical errors are 1 s .

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Appendix G (Continued) Appendix G (Continued) 388 Nevada Isotope Geochronology Laboratory Sample Descriptions Bowersox USF General Comments Your samples were run as conventional furnace step heating analyses. This type of sample run produces what is referred to as an ap parent age spectrum. The "apparent" derives from the fact that ages on an age spectrum plot are calculated assuming that the non-radiogenic argon (often referred to as trapped, or initial argon) is atmospheric in isotopic composition (40Ar/36Ar = 295.5). If there is excess argon in the sampl e (40Ar/36Ar > 295.5) then these ages will be older than the actual age of the sample. Ushaped age spectra are commonly associated with exc ess argon (the first few and final few steps often have lower radiogenic yields, thus apparent ages calculated for these steps are effected more by any excess argon present ), and this is often verified by isochron analysis, which utilizes the analytical da ta generated during the step heating run, but makes no assumption regarding the composition o f the non-radiogenic argon. Thus, isochrons can verify (or rule out) excess argon, an d isochron ages are usually preferred if a statistically valid regression is obtained (as ev idenced by the MSWD value). If such a sample yields no reliable isochron, the best estima te of the age is that the minimum on the age spectrum is a maximum age for the sample (i t could be affected by excess argon, the extent depending on the radiogenic yield). 40Ar/39Ar total gas ages are equivalent to K/Ar ages. Plateau ages are sometimes found, these are simply a segment of the age spectrum which consists of 3 or more steps, compris ing >50% of the total gas released, which overlap in age at the 2 s analytical error level (not including the 0.5% J-factor error, which is common to all steps). Such ages ar e preferred to total gas or maximum ages if obtained. However, in general an isochron a ge is the best estimate of the age of a sample, even if a plateau age is obtained. Your samples were ideally run as single crysta l laser fusion runs, however, due to crystal size and lack of abundant sanidine this app roach did not work. This type of analysis gives an apparent age for each individual crystal. Such data obviously allow us to directly verify if xenocrystic (or less commonly altered) crystals are present. If xenocrysts (or altered) crystals are present they a re discarded and an eruptive age calculated from the concordant group of juvenile ph enocrysts. These data can also be utilized to generate an isochron, in the same manne r as analyses from step heating runs. In general your samples appeared to be possibl y reworked. This is just from looking at the hand samples we received, clearly field obse rvations are critical here. Thus, the possibility that xenocrystic material was mixed in is a concern (see below). Because of the nature of the samples the data are rather compl ex and difficult to derive confident age control from. If you have questions after reading this feel free to contact me. 030202-05 Biotite This sample was run by the furnace step heating met hod. The age spectrum is very discordant, with ages ranging from initial hig h values over 200 Ma to lower values with progressive gas release. There is no plateau and the total gas age is 68.9 0.3 Ma. No valid isochrons were obtained. Statistically in valid isochrons (very high MSWDs)

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Appendix G (Continued) Appendix G (Continued) 389 indicate excess argon is present with 40Ar/36Ar values of ~320-330, and suggest ages of 23-33 Ma. Such data may be taken to suggest that the discordant age spectrum is a result of excess argon, but because of the high MSWD it ca nnot be used to define an age. You should be aware that two other possibilities exist for explaining this age spectrum; recoil loss of 39Ar from the biotite during irradiation (the crystal s were very thin) and the presence of xenocrystic biotite (since we could not run single crystals this could not be tested). Any of these processes will produce anoma lously old ages. In the absence of other information the best that can be done with th is sample is to state that the minimum age (21.7 Ma) is a maximum age for the sample. I b elieve this is substantially older than the expected stratigraphic age as you indicated. 030202.1 Plagioclase This sample was run by the furnace step heating met hod. The age spectrum is discordant, with high initial ages decreasing to ag es of ~5-6 Ma for the final ~80% gas released. There is no plateau and the total gas ag e is 11.6 0.2 Ma. The attempted isochron regressions failed to yield a statisticall y valid age, however, numerous isochrons with MSWDs slightly too high suggest ages of 5.5 Ma and all suggest excess argon with40Ar/36Ar values of ~340. Comments for the sample discusse d above apply here with the exception of recoiled 39Ar which should not be a concern for this sample. The best interpretation of this sample (most confident) is t hat the minimum age of 4.99 Ma is a maximum age for the sample.

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Appendix G (Continued) Appendix G (Continued) 390

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About the Author J. R ichard Bowers ox re ceived a Bachel or’s D egree in Geolo gy from San Diego State University in 1973 and Master’ s Degree in 1974. He worked a s a petroleum geologist in Bakersfield, California, f or 24 year s with Getty Oil Company and Texaco Inc (now Che vron Corp .), Mission Resourc es, I nc., and Baker sfield En ergy Resourc es, Inc. While with Bakersfield Ene rgy Resources he held positions of Geological Manag er, Corpora te Secre tary Direct or, and Pa rtner. F ollowing the succ essful sa le of Ba kersfie ld Energy in 1998, he entered the Ph.D. program at the Univer sity of South Florida in 1999. Mr. Bowersox has authored and co-authored numer ous publications in petroleum geology and paleontology While in the Ph.D. program at the University of South Florida he authored an article in Palaeogeography, Palaeoclimatology, and Palaeoecology and presented several papers at re gional and national meetings of the Geolog ical Society of America, American Association of Petroleum Geolog ists, and American Geophy sical Union.


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2006.
3 520
ABSTRACT: This study focuses on reconstructing the dynamics within the Pliocene San Joaquin Basin (SJB) molluscan fauna. This was accomplished by 'binning' the data within a constrained chronostratigraphic framework into: 1) 484 individual stratigraphically-ordered locality collections; 2.) 116 stratigraphically-sequential compiled ten-meter sample intervals; 3.) 15 intervals compiled by 4th-order eustatic cycles; 4.) three formation-level compiled samples; and 5.) the Etchegoin group fauna (informal San Joaquin Basin nomenclature) overall. These datasets were analyzed by inferential, multivariate, and descriptive statistics to examine local and regional environmental controls on faunal composition, community associations and distributions; cross-scale faunal structure; and large-scale environmental controls on immigration, diversity, and extinction. Primary environmental controls on community composition and spatial distribution were substrate type and water paleo-depth.^ ^Consequently, the Pliocene SJB record is one of a temporal succession of complexly distributed habitats and species. Regional habitat patchiness controlled individual locality-level (a1) diversity and contributed 62% of regional sample-level (a2) diversity. Endemic species comprise 30% of the fauna but account for 42% of a2 diversity, indicative of their environmental sensitivity. Partitioning a2 diversity between non-endemic and endemic species reveals habitats segmented as shared or available solely to endemic species. At the level of 4th-order eustatic variations, diversity between temporal samples (b1) accounts for ~80% of total (y) diversity consistent with eustatic control of faunal structure. During eustatic fluctuations, endemic habitats expanded and contracted at rates greater than shared habitats. Invading species quickly filled shared habitat during transgression and displaced endemic species during regression.^ ^Therefore, climatic- and regression-driven hydrologic change and productivity collapse in the Pliocene SJB led to seven extinctions of >40% species. Peak faunal diversity corresponded to periods of highest sea-levels whereas low-diversity faunas characterized low to rising sea levels. Thus, speciation events following extinctions suggest diversification of surviving faunas into habitats newly-created by changed environmental conditions.The broader implication of this study is that during current global sea level rise depleted endemic faunas of shallow-coastal and ocean-marginal environments will be displaced into the shared-habitat with consequent extinction likely if adaptation does not keep pace with environmental change.
502
Dissertation (Ph.D.)--University of South Florida, 2006.
504
Includes bibliographical references.
516
Text (Electronic dissertation) in PDF format.
538
System requirements: World Wide Web browser and PDF reader.
Mode of access: World Wide Web.
500
Title from PDF of title page.
Document formatted into pages; contains 390 pages.
Includes vita.
590
Adviser: Peter J. Harries, Ph.D.
653
Neogene
Chronostratigraphy.
Paleoecology.
Multivariate statistics.
Diversity.
690
Dissertations, Academic
z USF
x Geology
Doctoral.
773
t USF Electronic Theses and Dissertations.
4 856
u http://digital.lib.usf.edu/?e14.1805