Our new article is out in the Journal “Archaeology, Ethnology & Anthropology of Eurasia”. We studied the cross-sections of three sites in Orkhon valley (central Mongolia), containg the cultural sequences from the Final Middle Paleolithic to Late Upper Paleolithic. Here we present first results on paleoclimatic conditions, that might impacted on human occupation and depopulations in this valley.
This research is mostly based on geochemical analysis (REE, Sr and various geochemical indices) and faunal remains.
Collectively, our data indicate gradual aridification of a semi-arid to semi-humid climate in the Orkhon Valley during MIS-3 and -2. This conclusion is supported by the faunal complex reconstructed for the Khangai Mountains, representing the complex mammoth fauna of the steppe and forest-steppe ecozones. Taking into account radiometric dates of archaeological culture-bearing layers, features of identified lithic industries and their deposition, it can be concluded that human occupation of the Orkhon Valley was episodic, sporadic and of variable duration. Two discrete occurrences of human occupation have been established thus far at Moiltyn-am; one for the lithological unit including Layers 4–6, in which Layer 4 is redeposited, and one for Layer 3.
Remains of the large bovid – horse – sheep triad are most often found at these sites, while the occurrence of bovids, most likely represented by the Baikal yak, decreases with the period of aridification lasting from the Middle Paleolithic to the Early Upper Paleolithic. The diversity of human material culture documented in the study area is obviously associated with paleoecological and paleoclimatic parameters, the fluctuating availability of water resources supporting predictable availability of prey animals, and lithic raw materials suitable for stone tool production, as well as with a favorable geographical location on the pathways of migratory game. The available chronostratigraphic characteristics of sites in the Orkhon Valley are still insufficient for conclusions to be confidently drawn about the coexistence of different hominin groups exhibiting varying cultural characteristics. It is possible that ancestral human populations migrating through the valley did not often encounter one another due to what we perceive as short-term habitation of the currently known archaeological sites.
More data, including new OSL and radiocarbon dates, are coming and will be published later this year.