Pleistocene climate change, natural environments and palaeolithic occupation of the upper Yenisei area, south-central Siberia

The upper Yenisei River area, near the geographical centre of Asia, is of m ajor importance for mapping the Pleistocene climate evolution over Siberia. An extensive loess cover with a suite of buried palaeosols from the Northe rn Minusinsk Basin has provided one of the most complete. high resolution L ate Quaternary palaeoclimatic archives currently described in north-central Asia. Coupled with the pollen evidence. the loess-palaeosol records indica te establishment of periglacial steppe tundra during cold stadial intervals , replaced by parkland steppe and boreal forest during warm interstadial in tervals. Zonal transformations of the Pleistocene environments due to marke d climatic variations are reflected by the diversity of fossil faunal speci es, including non-analogue communities. Geoarchaeological records incorpora ted in the loess-palaeosol formations represent important palaeoenvironment al multi-proxy data complementing the fossil biotic and palaeopedological e vidence. Abundant "pebble tool" assemblages provide explicit evidence of hu man occupation of the upper Yenisei area prior to the last interglacial (> 130 ka BP). The morphological and technological variability of the palaeoli thic industries displaying a differential degree of patination and aeolian abrasion attest to several stages of the initial peopling of the southern S iberian territory. The cultural finds associated with the Middle Pleistocen e cold-adapted fossil fauna indicate that early humans were able to survive in local periglacial environments. Favourable climatic conditions during t he last interglacial promoted expansion of the more advanced Mousterian (Le vallois) tradition that persisted until the early last glacial stage (OIS 4 ). Warming during the mid-last glacial stage (OIS 3) accelerated formation of the Late Palaeolithic cultures dominated by developed blade reduction te chniques. Intervals of significant climatic deterioration and onset of full glacial conditions are manifested by the absence of my archaeological reco rd. The main focus of the current Quaternary investigations is to refine th e established chronological framework and detail contextual settings of the cultural records within the larger study area. (C) 2001 Published by Elsev ier Science Ltd.