The history of the marine basins in the North of Western Siberia during the Pleistocene

Abstract

Abstract During the Early and Middle Pleistocene and the early part of the Late Pleistocene persistent downwarping led to a major transgression in northern West Siberia, extending generally from the Polar Urals to the Central Siberian Plateau. This transgressive phase began in the Tobol'sk period of the Early Pleistocene and reached its maximum during Salekhard time; the Kazantsev period was largely a regressive phase. Minor regressions at the end of the Tobol'sk and Salekhard periods saw the accumulation of unstratified “drift‐like”; deposits in which transport by icebergs and sea ice played a major role. No continental ice sheets existed in this area during the traditional glacial epochs of the Early and Middle Pleistocene. Atlantic currents penetrated into the Kara paleobasin throughout most of the period in question, reaching as far east as Taymyr and as far south as Ust'‐Port. The resultant climatic amelioration resulted in forest tundra and northern tayga zones spreading 300 km north of their present boundaries.