Pre-Jurassic seismogeological complexes typification in the south-east of Western Siberia

Relevance. The heterogeneity of the lithological composition (alternation of carbonate, effusive, clay-siliceous and other rocks), steep angles of strata incidence, the neighborhood of ancient rocks with much younger rocks, tectonic activity evidences and metamorphosis processes make it difficult to predict the objects of the Pre-Jurassic depositional complex that are promising from the point of view of the presence of hydrocarbons. Object. Seismic wavefield of the Pre-Jurassic complex of deposits in the southeastern part of the West Siberian oil and gas province (Tomsk and Novosibirsk regions). Aim. Carrying out a morphological description followed by systematization of images of the seismic wave field of lithologically heterogeneous rocks of the Pre-Jurassic complex. Methods. The study of the seismic wave field behavior in various geological formations of the Pre-Jurassic depositional complex. Seismic stratigraphy and seismic formation analysis of time seismic sections. Generalization and systematization of accumulated data. Classification of various typical objects of the Pre-Jurassic complex according to the wave pattern. Results and conclusions. The author has typified the main seismogeological complexes of the Pre-Jurassic deposits of the south-east of Western Siberia (Tomsk and Novosibirsk regions). The considered criteria of seismogeological typification are recommended for assessing and zoning the seismic wave field of Paleozoic objects according to their degree of prospects. The limestones overlain by weathering crust, as well as monocline and submerged blocks of organogenic limestones and dolomites stand out most vividly on the seismic record. The protrusions of igneous rocks are least energetically pronounced. An additional seismogeological class of regular recording was identified. It is characterized by the deflection of the central part of blocks of horizontally layered rocks. This may be characteristic of clustic deposits (volcanogenic sedimentary formations of the Triassic), which may be unpromising in the deposits of the Pre- Jurassic complex in the territory under consideration. The aithor proposed the approaches for further development of the study.