FORMATION AND EVOLUTION OF THE RUSSIAN ARCTIC CRYOLITHOZONE (ON THE SHELF AND THE CONTINENT) IN THE PLEISTOCENE-HOLOCENE

Abstract

The paper addresses age nonuniformity of the permafrost of the Russian Arctic shelf. It has been widely accepted that recent permafrost exists on the present-day shelf, which was formed under subaerial conditions during shelf draining in the Late Pleistocene, was flooded during the subsequent transgression, and now exists as a relic zone. However, there is also modern permafrost forming under submarine conditions. The paper considers the mechanism of its formation. The author suggests a mechanism that involves bottom soil freezing and ice formation due to constant natural transformations in seabed sediments. The proposed mechanism is supported by analyzes of certain sections of the bottom sediments of shelf and of the Pleistocene marine plains (ancient shelves) composed of dislocated sequences with massive ice beds. Analysis of the massive ground ice genesis identified different geological history as well as different transgressive and regressive regime of the Russian Arctic western and eastern sectors. The glacial cover has limited distribution in the Russian North and was absent on the Russian Arctic and Subarctic plains to the East of the Kanin Peninsula.

Keywords

• massive ground ice
• sheet ice
• polygonal wedge ice
• subsea permafrost zone
• quaternary history of the russian arctic permafrost