ESR DATING FOR TREUGOL'NAYA CAVE, NORTHERN CAUCASUS MT., RUSSIA: RUSSIA'S OLDEST ARCHAEOLOGICAL SITE AND A THICK OXYGEN ISOTOPE STAGE 11 STRATIGRAPHIC SECTION

At 1510 m elevation, Treugol'naya Cave, Russia, is the highest cave showing evidence for human occupation in Eastern Europe. Along with abundant faunal remains, including the extinct Middle Pleistocene species, Equus altidens, Ursus deningeri, and Canis mosbachensis, Layers 4-7 in the 4.5-m-thick sequence yielded numerous choppers, sidescrapers, endscrapers, and protobifaces, representing Lower Paleolithic pebble and flake tool industries.

Electron spin resonance (ESR) can date tooth enamel from 10 ka to 5 Ma in age. To determine absolute ages for Treugol’naya, 35 independent subsamples from nine ungulate teeth collected from the Lower Paleolithic layers were dated by standard and isochron ESR analyses. Since hominids modified some of the ungulate bone fround in the site, dating these teeth dates the human activities. Individual volumetrically averaged external dose rates were determined for each tooth using radioactive element concentrations measured for 78 sediment samples. Isochron analyses indicate that the teeth experienced no significant U leaching or secondary uptake, and that linear uptake (LU) provides accurate ages. Assumptions about Rn loss and sedimentary water concentration do not significantly affect the LU ages. Layer 4d dated to 365 ± 12 ka, while Layer 4B averaged 375 ± 8 ka. Although one tooth from Layer 5d dated to 315 ± 10 ka, and was probably reworked from a higher layer, the other from Layer 5d dated at 406 ± 15 ka. Therefore, ESR, paleomagnetic, palynological and paleontological analyses all indicate that the Lower Paleolithic Layers 4-5 correlate with Oxygen Isotope Stage (OIS) 11. The thickness of Layers 4-5 (more than 1.5 m) make this one of the thickest OIS 11 terrestrial deposits known. Therefore, hominids visited the site periodically throughout OIS 11, indicating that they utilized resources at elevations > 1000 m at least seasonally by 400 ka.