The remarks on the mid-ocean ridges topography formed synchronously with sedimentation on their surface (using the Nansen and Amundsen Basins, Arctic Ocean, as an example)

A solution to the problem of the thermal regime of the forming oceanic lithosphere during sedimentation on its surface is presented. This allows us to assess the causes of the significant contrast in sea depths in the Nansen and Amundsen Basins, located in the Arctic Ocean on either side of the Gakkel Ridge. This paper examines the role of both the gravitational load and the thermal insulation effect of the accumulating sedimentary cover on the formation of the relief of the basins surrounding the ridge. It is shown that neglect for the thermal effect of sedimentation on sea depth in the basins in isostatic models leads to errors of several hundred meters. Estimated sea depths in the Nansen and Amundsen Basins, calculated for lithosphere of different ages, taking into account both the gravitational and thermal effects of sedimentation, are comparable to actual depths. The calculated differences in sea depth at reference points in the central regions of both basins are also close to the actual depths.

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