ESR at Treugol'naya Cave, Northern Caucasus Mt., Russia: Dating Russia's oldest archaeological site and paleoclimatic change in Oxygen Isotope Stage 11

To determine absolute ages for Treugol'naya, 32 independent subsamples from nine ungulate teeth collected from the Lower Paleolithic layers were dated by standard and isochron electron spin resonance (ESR) analyses. Isochron analyses indicate that the teeth experienced no significant U leaching or secondary uptake, and that linear uptake (LU) provides accurate ages. Layers 4Б through 5Б dated to 365±12-406±15 ka. Therefore, hominids visited the site periodically throughout Oxygen Isotope Stage (OIS) 11, indicating that they utilized resources at elevations >1000 m at least seasonally by 400 ka. ESR, paleomagnetic, palynological and paleontological analyses all indicate that the Lower Paleolithic Layers 4-5 correlate with OIS 11. The thickness of Layers 4-5 (more than 1.5 m) makes this one of the thickest OIS 11 terrestrial deposits known.