| Summary: | The genesis of deformed diamictons in near‐surface perennially frozen sediments and some characteristic landforms widespread in northern West Siberia are examined. The hypothesis of the Late Pleistocene glaciation of the Arctic shelf and adjacent plains in northern Eurasia is re‐evaluated. The accumulation of clastic‐boulder, unsorted diamicton‐type deposits took place under cold sea‐water conditions. Dislocations in near‐surface permafrost may be divided into lithogenic, cryogenic‐lithogenic and cryogenic types. They are related, first, to subaqueous sedimentation processes, and, second, to freezing of sediments after drainage of water bodies. The formation of well‐defined linear‐ridge topography (considered by some researchers as ice‐marginal features) located in some regions of northern West Siberia is related to neotectonics, lithology and fracture of Palaeogene deposits, their differential erosional‐denudational dissection, and subsequent frost heave.
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