Mathematical modeling is used to study the role of natural events in the evolution and current state of the permafrost zone and the gas hydrates stability zone in the northern part of the East Siberian shelf. One of the main events of the last 200 thousand years was the cover glaciation of the end of the Middle Pleistocene, which left sheet ice in the sediments of the Anzhu Islands (New Siberia and Faddeevsky), 20-30 m thick and 2-3 km long. A paleogeographic scenario of the shelf development in the last 200 thousand years and a geological structure model, which characterizes the composition and thermophysical properties of rocks, have been constructed. A model of thermophysical processes in the shelf sediments was used for a geological section with a thickness of 1500 m to calculate the temperature of the rocks. The simulation results showed the following. The permafrost thickness in the glacial region is 30-160 m less, and the base of the gas hydrate stability zone is located 140-600 m closer to the seabed surface than in non-glacial conditions.
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