The article shows the effect of organic porosity (or porosity in the texture of kerogen), formed as a result of the transformation of organic matter, on the accumulation of hydrocarbons. According to the classical ideas, the main function of source rocks is the generation of hydrocarbons. However, recently source rocks have been identified, which are not only a source of hydrocarbon formation, but also a place of their accumulation. Organic pores in the texture of the kerogen of these strata contribute significantly to the volume of the void space of newly formed reservoirs and, as a result, increase their resource potential. As an example of this phenomenon in the oil and gas bearing provinces of the Russian Federation, we can name the beds of the Bazhenov and Khadum formations, the Domanic Horizon and others, which are hybrid phenomena that combine both traditional and non-traditional accumulations of hydrocarbons. An example of the analysis of the organic matter of rocks from two wells in the southern part of the Pre-Urals foredeep (wells No. 35 Chiliksaiskaya, 176 Terektinskaya) by the Rock-Eval method examines the reasons for the retention of hydrocarbons by both the mineral matrix and parent rock kerogen, and also shows the effect of the kerogen surface on the retention of hydrocarbons. A quantitative assessment of the organic porosity of the studied rocks is given, which makes it possible to determine the predicted volumes of retention of hydrocarbons generated in the process of catagenesis. According to the results of the research, it has been established that at moderate depths of occurrence of source rocks, the release of hydrocarbons forms a porous surface that, in the first place, retains components of increased molecular mass and polarity. Detached from the surface of the kerogen, in the first place, light and saturated hydrocarbons, and only then heavy. However, in the deep-buried horizons, at an elevated temperature, the process of desorption becomes predominant. In such conditions, the influence of the level of development of pore space is reduced. Higher temperatures intensify the desorption of hydrocarbons to such an extent that the influence on the adsorption of organic pore space is leveled.
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