The seismic stratigraphy scheme for the shelf basins of the East Siberian Sea and the Chukchi Sea region and the adjacent deepwater area of the Amerasia basin has been developed, and mega-sequences (or tectonostratigraphic units) with the conventional ages of 125‒100, 100‒80, 80‒66, 66‒56, 46‒45, 45‒34, 34‒20, 20‒0 Ma are distinguished. Zhokhov foredeep basin of the Late Jurassic‒Neocomian age is distinguished between the New Siberia and the De Long islands. Three main phases of rifting are identified on the shelves in the region with ages of 125–100, 66–56, and 45–37 Ma. The main phase of continental rifting occurred in the Podvodnikov and Toll basins at 125‒100 Ma. The typical clinoform accumulation of sediments occurred at the edge of the shelf at 66–20 Ma. We identified three syntectonic epochs of the formation of clinoform sequences with the ages of 66–45, 45–34, and 34–20 Ma. The phase of uplifting and compression in the region of Wrangel Island happened at ≈66 Ma. The relatively monotonous tectonic setting with approximately the same thicknesses of the sedimentary cover began at 20 Ma.

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Sedimentological modeling is one of the important parts of basin modeling. Processes of sedimentation and sedimentation environment mostly determine the final structure and properties of the geological play. So, to solve the direct problem means to find out the lithological and facies cross-section, being based on initial sedimentation environments and processes. The solution of the direct problem allows us to predict lithology and facies distribution of play of interest. Spatial resolution of the sedimentological model can be rather high, up to centimeters. Solution of the inverse problem helps us to reconstruct initial environments and conditions of sedimentation. If we have solved the inverse problem for well-explored areas, we could extrapolate the results to adjacent unexplored areas and predict sedimentary structure by solving the direct problem. The designed Mazay2D forward sedimentary modelling software complex can perfom sedimentological modeling of erosion, distribution and accumulation of clastic deposits and formations, sedimentation and erosion of carbonate deposits (including reefs). Sedimentary modeling technology solves direct problem (we know environment – we can calculate final structure of the geological play) and inverse problem (we have final structure – we can calculate processes of its sedimentation). The direct problem solution allows us to calculate lithology, gradation, porosity, permeability, density and other petrophysical characteristics. Elastic parameters and synthetic seismic profile can also be calculated. Output data of sedimentological modelling can be used as input data in basin modeling to calculate, for example, porosity evolution during post-sedimentary stage. Sedimentary modeling can be used to predict high-resolution lithological and facies structure of the reservoir, to plan geophysical research and as assistance for seismic interpretation. Besides, sedimentological model can be applied to basin modeling of hydrocarbon systems.

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