ИСТИНА

According to the modern understanding, submarine permafrost (SP) in the Kara Sea shelf can be encountered in the area from the coastline up to the water depth of 120 m, which corresponds to decrease in the sea level during the Sartan cryochron (last glacial maximum of the Late Pleistocene). Potential depth of freezing and corresponding SP thickness could reach 400 to 500 m. Thus, one can presume that SP in the study area is relic. However, during the drilling in the deep-marine shelf of the south-east part of the Barents Sea, SP bodies shaped like ice stocks whose thickness exceeded 100 m and whose temperature was constant with depth were encountered. It was presumed that their formation occurred as a result of rapid degassing and overcooling of initially unfrozen gas-saturated sediments with temperatures close to the freezing temperature. So, SP of the continental shelf of the Kara and Barents Seas is represented by both relic and newly formed permafrost. Besides, modern permafrost formation occurs at low accumulative surfaces (e.g. Sharapovy and Marre-Sal’skiye Koshki).