Based on the processing of aerial photography (flights in 1952, 1974) and space photography (2014 and 2015) in a GIS environment, followed by the analysis of the spectral density graphs of erosion intensity, the parameters of the erosion of the Sakhalin coast were determined and the spatial structure of it was characterized. In 2011, in the area of the town of Nevelsk, Sakhalin Oblast, we began instrumental observations along a network of 100 benchmarks concreted into the surface of an argillite-siltstone bench coseismically uplifted as a result of the earthquake on August 2, 2007, in the area of the town of Nevelsk, Sakhalin region. As shown by a comparative analysis of the rates of destruction of benches and coastal ledges in rocks of weak and medium stability, the destruction of the latter occurs at rates approximately an order of magnitude greater than the rates of destruction of the surface of the coseismically uplifted bench. The maximum contribution to the destruction of the bench is made by frost weathering at negative air temperatures during the open sea period. The number of freezing and thawing cycles during this period in the conditions of the tidal sea reaches 100–150 cycles.