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Photographic And Sediment Monitoring Procedures And Initial Results For A Brazilian Iron Ore Cave

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Photographic And Sediment Monitoring Procedures And Initial Results For A Brazilian Iron Ore Cave
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Vitor Moura Instituto do Carste (Brazilian Karst Institute) Rua Brasópolis, 139 Belo Horizonte, Minas Gerais, 30.150-170, Brazil vmamoura@gmail.comet al. AbstractThe definition, development and application of monitoring procedures for caves are currently in demand in Brazil. The need for environmental licensing processes and effective environmental control actions has been increasing since the beginning of this century due to the intensification of economic activities. This work discusses the development of a method of photographic and sediment monitoring and the application of this method in an iron ore cave. This cave is located inside an industrial area currently under development by a mining company. This situation demands effective and specific environmental control measures. The method's simplicity, effectiveness and multidisciplinary approach indicate that it has potential for use in future works to define management decisions and protection measures for iron formation caves and other examples of karst heritage.
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Vitor Moura Instituto do Carste (Brazilian Karst Institute)
Rua Brasopolis, 139 Belo Horizonte, Minas Gerais, 30.150-170,
Brazil vmamoura@gmail.comet al.
AbstractThe definition, development and application of
monitoring procedures for caves are currently in demand in
Brazil. The need for environmental licensing processes and
effective environmental control actions has been increasing
since the beginning of this century due to the intensification
of economic activities. This work discusses the development of
a method of photographic and sediment monitoring and the
application of this method in an iron ore cave. This cave is
located inside an industrial area currently under development
by a mining company. This situation demands effective and
specific environmental control measures. The method's
simplicity, effectiveness and multidisciplinary approach
indicate that it has potential for use in future works to
define management decisions and protection measures for iron
formation caves and other examples of karst heritage.



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NCKRI SYMPOSIUM 20th National Cave and Karst Management Symposium152 Bats are the poster child for caves. Caves are a poster child for karst. Use the poster children to come out of the darkness.ReferencesBodenhamer, H., 1990, Coconino National Forest Cave Management Policy [unpublished]. British Columbia Ministry of Forests, 2003, Karst management handbook for British Columbia: http://www.for.gov.bc.ca/hfp/publications/00189/ Karst-Mgmt-Handbook-web.pdf (accessed May 2013). British Columbia Ministry of Forests, 2003, Karst Management Handbook Training: http://www. for.gov.bc.ca/hfp/training/00008/ (accessed May 2013). Dixon, R., 1991, Tonto National Forest Cave Resource Management Guide [unpublished]. Keeler, R. and Bohman, R., 2013, Arizona National Forest Cave and Karst Management Plan: http:// centralarizonagrotto.webstarts.com/index.html (accessed September, 2013). Nieland, J., 1994, Strategy for Cave Management XYZ National Forest (Gifford Pinchot NF), USFS Region 6 [unpublished]. U.S. Forest Service, 1990, Draft Cave management Plan for the Sierra Vista Ranger District Coronado National Forest [unpublished]. U.S. Forest Service, 1992, Tonto National Forest Cave Resource Management Guide [unpublished]. U.S. Forest Service, 1995, Lincoln National Forest Cave Ecosystem Management Direction, 45 pages plus appendices. U.S. Forest Service, 2008, Tongass National Forest Land and Resource Management Plan: http://tongassfpadjust.net/Documents/2008_Forest_Plan.pdf (accessed May 2013). U.S. Forest Service, 2009, Forest Service Manual, FSM 2300 Recreation, Wilderness, and Related Resource Management:Chapter 2350 Trail, River, and Similar Recreation Opportunities:2356 Cave Management, p. 69-77, http://www.fs.fed.us/ cdt/main/fsm_2350_2300_2009_2.pdf (accessed September 2013).

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20th National Cave and Karst Management Symposium NCKRI SYMPOSIUM 153 accurate and detailed cave mapping, geospeleological and biospeleological studies and multidisciplinary monitoring and management actions. In response to this new demand, the objective of this work is to develop, test and implement adequate methods to monitor environmental alterations in caves through the use of photographic and sediment monitoring techniques. Photographic monitoring is a broad-spectrum technique that is able to show alterations in different cave attributes such as speleothems, rock surfaces and structural features, among others. Sediment monitoring can be a sensitive environmental indicator, providing numeric data and allowing the quantitative analysis of the alterations. Cave location and geologic and environmental contextThe CAI-03 cave is located in the eastern escarpment of the southern part of the Espinhao Ridge (Figure 1), a collisional orogeny in southeast Brazil that was formed in the Mesoproterozoic Era. This ridge is composed mainly of quartzite, followed by phyllite, conglomerate and varied volcanic rocks (Carste, 2012). The Espinhao Ridge, a UNESCO biosphere reserve, acts as a hydrographic boundary between three important river basins. The eastern escarpment is characterized by forest vegetation and a humid tropical climate that differs from that on the western side. Iron formations with economic interest occur discontinuously in this complex geologic context and are Abstract monitoring procedures for caves are currently in demand in Brazil. The need for environmental licensing processes and effective environmental control actions has been increasing since the beginning of this century due to the This work discusses the development of a method of photographic and sediment monitoring and the application of this method in an iron ore cave. This cave is located inside an industrial area currently under development by a mining company. This situation measures. The methods simplicity, effectiveness and multidisciplinary approach indicate that it has potential and protection measures for iron formation caves and other examples of karst heritage.IntroductionSince the Federal Constitution Laws Revision in 1988, Brazil has experienced a substantial increase in the studies related to environmental licensing. The New Federal Constitution includes a new approach to the environmental issues and affects all the major development initiatives in mining, energy generation, transport infrastructure, and urbanization. This increase was especially notable from the beginning of the 21st century, when studies to protect and control effects on caves became more common. This broad Carste Associated Consultants Ltd. Rua Braspolis, 139 Belo Horizonte, Minas Gerais, 30.150-170, Brazil marina.leao@carste.com.brLuciana AltInstituto do Carste (Brazilian Karst Institute) Rua Braspolis, 139 Belo Horizonte, Minas Gerais, 30.150-170, Brazil lualt1@gmail.comVitor MouraInstituto do Carste (Brazilian Karst Institute) Rua Braspolis, 139 Belo Horizonte, Minas Gerais, 30.150-170, Brazil vmamoura@gmail.comAugusto S. AulerInstituto do Carste (Brazilian Karst Institute) Rua Braspolis, 139 Belo Horizonte, Minas Gerais, 30.150-170, Brazil aauler@gmail.comPHOTOGRAPHIC AND SEDIMENT MONITORING PROCEDURES AND INITIAL RESUL TS FOR A BRAZILIAN IRON ORE CAVE

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NCKRI SYMPOSIUM 20th National Cave and Karst Management Symposium154Cave morphology and monitoring conditionsThe CAI-03 cave is 74 meters long and 2.5 meters deep and has an area of 396 m2 and a volume of approximately 485 m3. Despite its small volume in comparison with caves in iron formation cave in Brazil. From the entrance room (Figure 2), after a restriction, the cave extends as two parallel passages heading south and southwest. In some chambers, one can observe contact between the banded iron formation and lateritic crust, which is prominent in the entrance room ceiling and walls (Figure 3). The and centimeter-long clasts in the entrance room and by sandy sediments forming a smooth ascending slope in and this water reappears in a small spring at the northeast of the entrance room. As iron formation caves are very The cave presents some challenges to photographic monitoring due to the small size of some chambers and the strong interference with compasses caused enclosed by quartzite, conglomerates and phyllite rocks. The CAI-03 is part of a local ridge named Serra do Sapo, a more resistant prominence sustained by banded iron formation rocks (Carste, 2012). The east part of the Espinhao Ridge was a site of gold exploration in the 18th century. This activity resulted in the development of cities that caused different grades of environmental alteration. Currently, the area is in the initial economic exploration process, focusing on iron ore extraction, and this process is led by different mining companies. In this age of new exploration, the caves remain an important heritage site to be studied and protected. The CAI-03 cave is located within a mining company area that is in the initial process of implementation. It is positioned on the lower part of a slope characterized by the presence of sparse escarpments surrounded by tropical forest. The cave is located in a preliminary protected area with restricted access that is to be converted into a private protected area owned by the mining company. Some measures have been taken to control to the effects on the cave, such as the installation of procedures and a monitoring program.Figure 1. Location of the CAI-03 cave.

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20th National Cave and Karst Management Symposium NCKRI SYMPOSIUM 1552007). Both methods are adequate for large volume caves where small variations in image framing are not critical. In the morphological context of the CAI-03 cave, which has small chambers and passages, it is critical to ensure an accurate repetition of images. Due to the small distance between the camera and the surfaces, it is important to avoid variations in image framing and camera location. Marking of the fixed stations One of the main challenges in photographic monitoring work is establishing adequate, durable and low-impact reproduction of the images. In CAI-03, monitoring was of stainless steel and yellow plastic tape (Figure 4). adequate material for use in cave environments and in direct contact with sediments. The plastic tape is less durable but has a lifespan compatible with the duration of the monitoring work. Angular registration method A commonly used method to record the angles of photographs in caves is to measure the azimuth with a compass and inclinations with a clinometer. However, in iron ore caves, it is necessary to avoid compass measurements due the magnetic interference. This interference has a random behavior, and variations of more than 20 degrees are common. To avoid this problem, we have developed a method based on the measurement by the magnetite present in the iron rock formations. MethodsPhotographic monitoringPhotographic monitoring is a fundamental tool for monitoring environmental alterations in caves. With this systematic record, alterations in physical, biotic and cultural photographic monitoring must be based on the construction of a dynamic image databank. The images must be taken time period (Hildreth-Werker, 2006). Some monitoring efforts have achieved effective results processes and the effects of visitation on caves. One of these efforts applied mapping based on the use of GIS software, such as ArcGIS and Compass (Hale, 2008). to record the conditions of image capture (Furhmann, Figure 3. View of a passage, showing the ceiling formed by lateritic crust and the flat sandy floor.Figure 2. View of the entrance.Figure 4. Flag used as fixed station marker.

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NCKRI SYMPOSIUM 20th National Cave and Karst Management Symposium156small distances between the camera and the surfaces being monitored. The digital images were captured as RAW (Digital future image processing. For capture, the SLR camera used, and both were set in auto mode to facilitate the reproduction of the images. During shooting, a 20 cm yellow scale was used, which was easily viewed against the sediment or rock surfaces. All images were converted to JPEG format, and a frame added to ease the accurate description of the image characteristics and future alterations in the environment (Figure 7). The images were organized in a databank permitting easy access and addition, which was standardized by the use of the same frame and tags. The representation on the cave map is useful to understand how the cave surfaces were recorded and to promote In this method, the tripod is positioned and leveled angle is recorded assuming that the line between the two for the use of a compass. The vertical angle is measured directly with the proper graduated disk for each image clinometer measurements (Figure 6). Image capture, processing and recording In addition to the CAI-03 cave, another 33 caves Nikon D-200 digital camera with a NikkorAF 1870 mm f/3.5-4.5 ED-IF AF-S DX lens and a Nikon SB-800 dedicated TTL speedlight were used. A second monitoring visit was performed only in CAI03 in October 2012. At this time, one super wide-angle Tamrom 10-24 mm f/3.5-4.5 DI-II LD Aspherical (IF) AF lens was added to the prior equipment. This lens Figure 5. Top, image showing one target flag (white arrow). Bottom, close-up view of the modified tripod base with a graduated disk with a 0to 360-degree range (red arrow). Figure 6.

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20th National Cave and Karst Management Symposium NCKRI SYMPOSIUM 157 A red line represents each images horizontal angle, indicating the features covered by the image. This cartographic representation ensures a multidisciplinary approach that enables the accurate reproduction of the images.Sediment monitoringMonitoring sediment deposits in caves is a useful tool to understand and control environmental changes over time. In theory, this process will record local variations in the sediment banks inside the cave through quantitative analysis of both depositional and erosional areas. For this monitoring, stainless steel erosion pins were used in accordance with the methodology described Figure 7. Image processed with the addition of tion tag. Figure 8. CAI-03 cave map showing the fixed stations, target flags, horizontal angles and reference numbers of the images.

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NCKRI SYMPOSIUM 20th National Cave and Karst Management Symposium158Results and discussion Photographic monitoring: initial results After nearly two years, some alteration in the caves sandy sediments is visible in the images. A comparison of images for the southern passage of the cave (Figure 10) shows that the area initially had many drip marks on the floor (image bottom). Due to the trampling in this area, the image from 2012 shows the loss of these drip marks and reveals a new dark spot. During the photographic monitoring interval, the cave was also the subject of a monthly geospeleological monitoring process. This intense activity and other visitation events resulted in the trampling because the cave had no marked trail to control cavers routes. passage reveals the loss of a drip concentration area over the same interval. This spot is indicated in the December in Hudson (1993) and adapted from Cole (1985) and After installation, the height of each pin was measured in millimeters with a laser meter. Three measurements were taken for each pin to ensure the correct registration of the height relative to the surface of the sediment (Figure 9). for each pin was calculated. The 15 erosion pins were installed in the cave during October 2012, at the beginning of the rainy season. A total of 6 pins were installed in accumulation areas or ponds, and 9 were installed in water input areas. The goal was to detect aggradation with the accumulation area pins and sediment loss with the water input area pins. In the case of a major sediment modification in the cave, this erosion pin network will be able to record the alterations both qualitatively and quantitatively. Figure 9. Erosion pin being measured with a laser meter. Figure 10. Top: photographic monitoring image of the southern passage of the CAI-03 cave from December 2010. Bottom: image from October 2012.

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20th National Cave and Karst Management Symposium NCKRI SYMPOSIUM 159in the 2012 image, anthropic activity remains the most probable cause for the alteration. In the 2010 image, a round and dark clast in the A6 quadrant is visible. In the 2012 image, this clast seems to be turned upside down and moved to the A4 quadrant (red arrow). 2010 image with a red arrow (Figure 11). Radial spreading of sandy sediments by drips is responsible for this feature. The 2012 image shows disturbed sediment in this area, and it is impossible to identify the original drip concentration. The initial photographic monitoring results for CAI03 also reveal the potential to record changes in clast A clast not previously recorded is visible in the image taken from the southeast part of the entrance room (visible in the 2012 image red arrow Figure 12). This alteration was most likely caused by anthropic activity during the biospeleological monitoring or other visitation activity. In iron formation caves, it is relatively common for a clast to fall from the lateritic crust. However, in this case, the fall has to be by the clast detachment. As there is no roof scar visible Figure 11. Top: photographic monitoring image of the southwest passage from December 2010. Bottom: image from October 2012. Figure 12. Top: photographic monitoring image of the southeast part of the entrance room from December 2010. Bottom; image from October 2012.Table 1. Heights of the CAI-03 cave erosion pins in October 2012 and April 2013.

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NCKRI SYMPOSIUM 20th National Cave and Karst Management Symposium160Sediment monitoring: initial results were measured again at the end of rainy season. From the total, only two pins indicate aggradation, and the other 13 record sediment loss (Table 1). 2 millimeters (yellow), low between 2 and 5 millimeters (orange) and high above 5 millimeters (red). Negative variation values indicate sediment loss, and positive values indicate aggradation. The number 1D erosion pin indicates a strong sediment loss of 41.3 millimeters over the 5-month interval. The Figure 13. View of the area around the number 2A erosion pin with a concentration of new drip marks, one of which was at the erosion pins base and caused sediment loss. Figure 14. CAI-03 cave map showing the sediment monitoring stations and a schematic of the water flow.

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20th National Cave and Karst Management Symposium NCKRI SYMPOSIUM 161after this simple action, it was possible to note drip marks developing outside the delimited trail (Figure 15). The use of inexpensive materials and simple techniques permits the application of this method in other caves by minimally trained personnel. be easily removed from the cave without causing any environmental alteration. This minimum-impact approach is fundamental in cave monitoring actions. ReferencesCarste Associated Consultant Ltd., 2012, Environmental Licensing reports of CAI-03 cave (part) Geologic and Geomorphologic context: Belo Horizonte, 11p. Cole, D. N., 1983, Assessing and Monitoring Backcountry Trail Conditions: United States Department of Agriculture Forest Service, Intermountain Forest and Range Experiment Station, 10p. Fuhrmann, K., 2007, Monitoring the disappearance of a perennial ice deposit in Merrill Cave: Journal of Cave and Karst Studies, v.69, no.2, p. 256-265. Hale, E. 2008, Protecting Oregon Caves: ArcNews Summer Issue: http://www.esri.com/news/ arcnews/summer08articles/protecting-oregoncaves.html. (accessed April 2010). Hildreth-Werker, V., 2006, Photographs as Cave Management Tools, in Hildreth-Werker, V. and Werker, J.C., eds., Cave Conservation and Restoration: Huntsville, National Speleological Society, p. 203-214. Hudson. N. W., 1993, Field Measurement of soil erosion and runoff: Food and Agriculture Organization of United Nations Soils Bulletin, v.68, 141p. Moura, V. M. A., 2011, Anlise Ambiental de trilhas em unidades de conservao Parque Nacional do Capara, MG (Environmental Trail Analysis in Protected Areas Capara National Park, Minas Gerais state, Brazil) [Ph.D dissertation]: Belo Horizonte, UFMG Minas Gerais Federal University/ Geociences Institute, 146p. Werker, J.C., 2006, Materials Considerations for Cave Installations,. in Cave Conservation and Restoration, 2006 edition, Huntsville: National Speleological Society, p. 167-174. pins location in a water input area helps explain the sediment loss, but other measurements will be necessary to better understand the extreme sediment loss. The number 2A erosion pin revealed the second highest sediment loss, totaling 7.3 millimeters of variation in 5.5 months. During the second measurement trip, one sediment loss (Figure 13). The ability to locate the erosion pins on the cave map was very important for visualization and to support further analysis (Figure 14). On this map, the water input and output points were located, as well as the accumulation areas. The location of the number 1D erosion pin most likely indicates the main water input point of the CAI-03 cave.ConclusionsThe photographic and sediment monitoring in the CAI03 cave demonstrates the usefulness of these techniques for recording environmental alterations, understanding cave dynamics and supporting further analysis. These monitoring results can serve as valuable tools especially for geospeleological, sedimentological and management analysis. This study demonstrates that the frequency of speleological monitoring was excessive, causing major sediment perturbation. In management terms, this result demands a reduction in the number of speleologic monitoring visits to protect the caves attributes. Trail delimitation was another management decision that followed the results of this monitoring. A few months Figure 15. View of the trail delimited after the photographic monitoring analysis.