Main regularities of periglacial phenomena evolution at Preduralye and Zauralye Plains

Abstract

Processes of periglacial litho- and morphogenesis were active at the plains to the West and East of the Urals during Pleistocene. Cryoeluvium, sand and loess eolian covers were formed at interfluvial surfaces. Cryogenous processes were dominating in morphogenesis such as frost cracking and polygonal microrelief formation. Slope wash and solifluction acted with considerable intensity at slopes. Rivers accumulated periglacial alluvium. Three subzones are distinguished within the periglacial hyperzone of the last Ice Age: northern (extremely cryoarid), central (cryo-semihumid) and southern (cryo-semiarid), the subzones differ both in rate and direction of litho- and morphogenetic processes.