The most geologically complex ranges in Western Siberia are the deposits of the Neocomian wedge-formed complex. The Neocomian range is promising in terms of oil and gas and is the main target for the fields being developed in the region. As a result of seismic facies and dynamic analysis of 3D seismic survey materials, with generalization of core and field geophysical data, a presence of large landslide bodies in the wedge-formed part of the Neocomian complex was revealed, due to the growth of local structures and active tectonic processes. The formation of interest is represented by a series of formation members, within the boundaries of which several dozen hydrodynamically isolated hydrocarbon deposits were identified. In the range of target reflecting horizons, spectral decomposition was calculated, the results were used to identify promising objects associated with paleo-flows; maps of effective thicknesses were constructed for individual formation members; areas of clayization and absence of sediments were mapped. The boundaries of structural- lithological deposits and lithological traps were clarified. The results of the geometrization of deposits within each of the identified reservoir bodies and the forecast of the distribution of effective oil-bearing thicknesses enabled to estimate geological oil reserves and refine geological models for the production wells placement. The results of work on the forecasting and geometrization of productive sand bodies in the slope part of the Neocomian complex using 3D seismic materials are the main sources of information for refining geological models, reliable assessment of hydrocarbon reserves and design of production drilling.
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