REVEALING SLOVENIA'S LATE PLEISTOCENE PALEOCLIMATIC, SEDIMENTOLOGICAL, AND CULTURAL HISTORY BY ESR DATING AND CAVE SEDIMENT ANALYSES AT DIVJE BABE I

At Divje Babe I, Slovenia's oldest archaeological site, the thick archaeological sequence housed Mousterian artefacts, including hearths, a perforated ursid femur flute, and bone tools, plus more than 200,000 cave bear (Ursus spelaeus) skeletal remains. Eleven archaeological layers were dated by 44 independent standard ESR analyses. Volumetrically averaged external dose rates were calculated from 146 sedimentary component samples analyzed by NAA.

Sedimentary features, including cryoturbation, cryoclasis, éboulis, secondary aggregate cementation, show that strong Late Pleistocene climatic fluctuations affected Divje Babe I, when hominids intermittently visited there discarding Mousterian artefacts. At least three rapid sedimentation phases alternated with depositional hiati. From 116 to 102 ka in Oxygen Isotope Stage (OIS) 5d, continuous sedimentation at 0.02 cm/y deposited Layers 23 to 17a2b under warm, dry to moderately humid conditions. In OIS 5b-5c, sedimentation slowed dramatically or ceased until approximately 85 ka. At 85-80 ka in OIS 5a, Dansgaard-Öschger (DO) Event 21, sedimentation averaged 0.036 cm/y depositing Layers 17a2a to 13 under warm, but dry to moderately dry conditions. The next hiatus spanned the first cold phase in OIS 4 from 80 to about 70 ka. From about 70-55 ka in OIS 4, deposition at approximately 0.012 cm/y resumed yielding Layers 12 to 8a under cool to cold, humid conditions. The flute was made and abandoned at about 60 ka. Early OIS 3 at 55-50 ka saw little or no sedimentation. In OIS 3 from 50 to 38-40 ka, rapid sedimentation resumed at approximately 0.04 cm/y depositing Layers 7 to 2 under conditions that varied widely from very cold to moderately warm, and from dry to moderately humid in the Mörshoofd-Glinde and Hengelo Interstadials, DO 14-10. Layer 2, with Early Aurignacian tools deposited under interstadial conditions ends the Pleistocene deposits. OIS 2 saw deep cryoturbation disturb Layers 2-5a. After a 28-30 ky halt, modest sedimentation resumed in the Early Holocene.