LATE QUATERNARY SAND COVERS OF CENTRAL YAKUTIA (EASTERN SIBERIA): STRUCTURE, FACIES COMPOSITION AND PALEOENVIRONMENT SIGNIFICANCE
A.A. Galanin
Melnikov Permafrost Institute, SB RAS, Merzlotnaya str. 36, Yakutsk, 677010, Russia
Keywords: Aeolian formation, D’olkuminskaya Series, cryogenic-aeolian, niveo-aeolian lamination, desertification, Late Pleistocene, Holocene, Bolling, Allerod, Younger Dryas, Eastern Siberia
Abstract
An additional comprehensive study of the Peschanaya Gora (Sand Hill) outcrop and other sections of aeolian coversands in Central Yakutia has revealed that, together with loess-ice (Yedoma) covers, they were two related granulometric and mineralogical derivatives, which had formed as a result of aeolian processing of Quaternary alluvium during the second half of the Late Neopleistocene. Episodes of desertification took place 22.0-14.0, 12.8-11.8, and 0.6-0.1 ka BP. A decrease in aeolian activity and consolidation of dune massifs by a soil-vegetative cover took place in the intervals of 14.0-13.0 and 10.0-0.6 ka BP. The largest episode of desertification took place during the last global thermic minimum (MIS-2) and led to a sharp decline in the mammoth biome, the disappearance of the wooly mammoth and rhinoceros in Central Yakutia.
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