Optical dating of sediment samples from Chagyrskaya Cave
- Permanent Link:
- Optical dating of sediment samples from Chagyrskaya Cave
- Roberts, Richard G.
- Publication Date:
- Subjects / Keywords:
- Optical Dating ( local )
Sediment Samples ( local )
Chagyrskaya Cave ( local )
- serial ( sobekcm )
- The existing chronology for the Chagyrskaya Cave is based on 19 radiocarbon (14C) age determinations (Derevianko et al., 2013; Rudaya et al., 2017) made on bison bones from stratigraphic layers 5 (n = 2) and 6 (n = 17). Several of the bones from layer 6 have cut marks consistent with those made by stone tools. Except for the uppermost sample from layer 5 (which has a calendar-year 14C age of 37,670â€“38,690 cal. BP at the 95 % confidence interval), all other age estimates fell at or beyond the reliable dating limit for these materials (Wood, 2015) and the current ceiling on 14C age calibration of c. 50,000 cal. BP (Reimer et al., 2013). Minimum (infinite) measured ages of 49,000 BP and 52,000 BP were obtained for 9 and 6 of the samples, respectively (Derevianko et al., 2013; Rudaya et al., 2017).
The 14C chronology for Chagyrskaya Cave indicates, therefore, that layer 6, the underlying layer 7 and part of the overlying layer 5 were deposited 50,000 years or more ago. Finite ages for these deposits can be obtained by optical dating of the sediments, which provides an estimate of the time since grains of luminescent minerals, such as quartz and potassium-rich feldspar (K-feldspar), were last exposed to sunlight (Huntley, Godfrey-Smith, Thewalt, 1985; Hütt, Jaek, Tchonka, 1988; Aitken, 1998; Jacobs, Roberts, 2007; Wintle, 2014; Roberts et al., 2015). The burial age is estimated by dividing the equivalent dose (De, a measure of the radiation energy absorbed by grains during their period of burial) by the environmental dose rate (the rate of supply of ionising radiation to the grains over the same period). The De is determined from laboratory measurements of the optically stimulated luminescence (OSL) from quartz or the infrared stimulated luminescence (IRSL) from K-feldspar, and the dose rate is estimated from field and laboratory measurements of environmental radioactivity, plus the small contribution from cosmic rays.
Each of these minerals has advantages and shortcomings compared to the other. In particular, the qua
- Source Institution:
- University of South Florida Library
- Holding Location:
- University of South Florida
- Rights Management:
- This object is protected by copyright, and is made available here for research and educational purposes. Permission to reuse, publish, or reproduce the object beyond the bounds of Fair Use or other exemptions to copyright law must be obtained from the copyright holder.
No images or PDF downloads are available for this resource.
Cras ut cursus ante, a fringilla nunc. Mauris lorem nunc, cursus sit amet enim ac, vehicula vestibulum mi. Mauris viverra nisl vel enim faucibus porta. Praesent sit amet ornare diam, non finibus nulla.
Cras efficitur magna et sapien varius, luctus ullamcorper dolor convallis. Orci varius natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Fusce sit amet justo ut erat laoreet congue sed a ante.
Phasellus ornare in augue eu imperdiet. Donec malesuada sapien ante, at vehicula orci tempor molestie. Proin vitae urna elit. Pellentesque vitae nisi et diam euismod malesuada aliquet non erat.
Nunc fringilla dolor ut dictum placerat. Proin ac neque rutrum, consectetur ligula id, laoreet ligula. Nulla lorem massa, consectetur vitae consequat in, lobortis at dolor. Nunc sed leo odio.