Today the Eastern Russian Arctic is the least studied region of the world. Anyway there are some sedimentary basins with thick deposits and probable high oil and gas potential. Sedimentary basins mostly filled with Aptian-Cenozoic sediments. In some areas the presence of an older Paleozoic cover is assumed. Terrigenous clinoform complexes of Cretaceous and Cenozoic age are the main target of this study. The sequence stratigraphic analysis is the most suitable method for detailed understanding of the internal geological structure of clinoform complexes today. This analysis was based on reference seismic profiles located in the Northern part of the East Siberian and Chukchi seas. The interpretation was carried out with the use geological and geophysical data for wells of the US sector of the Chukchi sea, Aion-1, ACEX, as well as using the results of the outcrops studies of the continental margins of the Eastern Arctic seas and the islands. Detailed study let to identify sequence boundaries, transgressive and maximum flooding surfaces and system tracts. Using the results of interpretation of reference seismic profiles, Wheeler (chronostratigraphic) diagrams were constructed and synchronous regional events, transgressions and regressions, were identified. Transgressive and regressive cycles in deposits were established. The Cretaceous clinoform complex has a predominantly regressive structure, and the Cenozoic clinoform complex includes two transgressive and regressive cycles. Regressive and transgressive trends allowed to clarify the stratigraphic position of sections. Four major transgressive and regressive cycles divided by regional boundaries were established for the entire sedimentary section. The lower boundary corresponds to a global flooding in Thanetian age (the Paleocene). The coastline moved inside mainland for hundreds kilometers. The second boundary is also consistent with a global flood, set in Lutetian time (middle Eocene), and then the trend became a regressive one. The next regional boundary corresponds to the erosional stage in Barton time (middle Eocene) and marks the end of regression and the beginning of transgression. The upper boundary corresponds to the stage of flooding, established in the Priabonian time (late Eocene). Later the trend of sedimentation became regressive up to the present time. As a result, a comprehensive analysis allowed Rosneft Oil Company to clarify the age and conditions of formation of Mesozoic and Cenozoic sediments, as well as the forecast of the presence and distribution of elements of hydrocarbon systems (detecting the intervals of regional reservoirs, source rocks, seals).
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