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New AMS radiocarbon dates from Kostenki 12

A new group of AMS 14 C age determinations have been obtained from the Oxford Radiocarbon Accelerator Unit for samples taken from lithological layers 12, 14 and 18 at the site of Kostenki 12. Dated as part of the EFCHED initiative, the new samples come from cultural horizons III, IV and V that underlie the volcanic Y5 Campanian Ignimbrite tephra horizon. Preliminary age correction of the AMS measurements for the effects of fluctuation in 14 C production suggests that the deposits were laid down prior to 40,000 calendar years ago. Comparison with the associated OSL dates of S. L. Forman (2006) shows that whilst there is broad general agreement between the respective dating methods, a significant age offset is still observable suggesting that further chronological investigation remains to be done. Introduction This is a short report on a recent set of AMS radiocarbon age determinations from the lowermost and oldest horizons at Kostenki 12. The samples, all of which comprised of charcoal too small to be botanically characterised, were collected in the summer of 2004 by M V Anikovich and given to the AMS radiocarbon dating facility in Oxford University in 2005 by R A Housley as part of the UK’s NERC funded EFCHED (Environmental Factors in the Chronology of Human Evolution and Dispersal) initiative. The Palaeolithic site of Kostenki 12 is located where the second terrace along the main valley of the Don River merges with the second terrace running along the south side of Pokrovskii Ravine. A series of radiocarbon samples were collected for analysis, of which six have been dated. Two samples (EFD5C505, N1 and EFD5C512, N8) are associated with the Lower Humic Bed (LHB), a dark brown calcareous loam, at the base of which lies cultural horizon III (CL III) (Holliday et al., 2006). The Y5 Campanian ignimbrite volcanic eruption horizon is believed to be present in a series of silts that lie between the Lower Humic Bed and the Upper Humic Bed. This horizon therefore provides a terminus ante quem for all the samples dated here. A single sample (EFD5C513, N9) is associated with Unit 1C that comprises of lenses of pale brown and lighter brown loam within which is located cultural horizon IV (CL IV). The remaining three samples (EFD5C514, 516 and 517; N10, N12 and N13 respectively) were collected from Unit 1A, a series of brown and light yellowish brown loam lenses that bear some similarity to a Humic Bed. These three samples are associated with cultural horizon V (CL V).