Late Pleistocene Paleoenvironments And Episodic Human Occupations In The Orkhon Valley Of Central Mongolia

Here, we present initial results of a new course of research being carried out at the Moiltyn-am, Orkhon-1, and Orkhon-7 Paleolithic sites in the Orkhon River Valley, central Mongolia. Our research focuses on the Moiltyn-am site, which preserves a cultural and chronological sequence from the Final Middle to the Late Upper Paleolithic. Results from analyses of rare earth elements, Strontium (Sr) isotopes, and faunal assemblages are correlated with data on paleoenvironmental conditions in the region during MIS-3 and MIS-2. Our conclusions are based in part upon post-depositional changes detectable in archaeological material from cultural layers at the Moiltyn-am site revealed through convergent analyses of stratigraphy, sedimentology, planigraphy, and the comparison of Sr isotopes in sediments and osteological remains. XRF-derived geochemical data from the Moiltyn-am sedimentary sequence yields evidence of past climatic conditions. We correlated these data with human occupational episodes in the Orkhon Valley during the Middle and Upper Paleolithic, and the results are analyzed in the context of extant paleoenvironmental information from northern Mongolia. Our results indicate a relatively humid climate prevailed during MIS-3, followed by a period of aridification, and the redeposition of sediments at Moiltyn-am. Faunal analysis reveals that Bos sp. and equids were the principal prey species for humans in the Final Middle to Initial Upper Paleolithic, supplemented by members of the Caprinae during the Early Upper Paleolithic. A complex mammoth fauna inhabited forest-steppe and steppe landscapes in the Khangai Mountains during MIS-3 and MIS-2.