In the article, in addition to the existing scientific studies, the prospects of the oil and gas content of Paleogene clayey rocks of the Eastern Ciscaucasia are examined on the basis of a detailed study of the neotectonic development of the studied region. The main tectonic elements affecting the geodynamics of the entire Caucasus are the two large lithospheric plates - the Scythian and Arabian. As a result of the interaction of these plates, the North Caucasus region tectonically represents a zone of collision, characterized by a stretching in the sublatitudinal direction, compression deformation in the submeridional direction, and a general uplift with the mountain system of the Greater Caucasus.
The degree of geodynamic activity of the territory under consideration was estimated from the velocity maps of modern vertical and horizontal movements, according to which the Eastern Ciscaucasia as a whole is subjected to intensive geotectonic processes, and in particular, experiences uneven ascent, which contributes to the formation of cracks and their opening. Due to the interaction of lithospheric plates accompanied by earthquakes, as is known, disruptive disturbances that affect the capacitive-filtration properties of rocks are formed. The paper analyzes the data on the strongest earthquakes within the study area. The authors built a map of the trend of movement of the foundation blocks. On the basis of which it turned out that the Stavropol arch and the Prikum system of uplifts rendered the greatest influence on the territory under consideration, as well as the depression region of the Tersko-Caspian advanced trough. The Nogai step and the Mineralovodsky protrusion move upward, without affecting the neighboring blocks. Depressions of the Manychy troughs zone drag only one adjacent block downward. The movement of all other blocks is subordinate. Thus, on the basis of the constructions, zones stretching and compression zones are identified.
Geological and geochemical studies were carried out to assess the oil and gas potential of the study area. Based on the data of pyrolytic (in the Rock-Eval modification) and chemical-bituminological analysis methods, clayey rocks of the Paleogene (Khadum, Kumsko-Keresinsky formation) belong to oil and gas bearing strata with a high oil and gas generation potential.
On the basis of neotectonic and geological-geochemical criteria, the paper proposes a scheme for the prospects of oil and gas potential of Paleogene clay rocks of the region under study. Thus, in the studied territory, Paleogene sediments have all the prerequisites for the industrial development of hydrocarbon accumulations. The main attention, from the position of neotectonics, deserves the zone of the greatest geodynamic activity: zones of epicenters of earthquakes, zones of faults or faults, zones of opening of cracks in hills foundation.
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