Статья посвящена эволюции понятия «трудноизвлекаемые запасы» в России и конкретным геологическим объектам Татарстана, которые подпадают под это определение. Существует разрыв между законодательной базой, налоговой политикой и реальным состоянием ресурсной базы. Показан региональный опыт работы с нетрадиционными углеводородами. Каждый тип трудноизвлекаемых запасов (доманикиты, сверхвязкая нефть, угли, сланцы) требует собственной методики изучения и системы разработки, а действующие налоговые условия делают их массовое освоение нерентабельным.

The article is devoted to the analysis of the current state and priority areas of scientific and technological development of the oil and gas complex of Russia in the context of geopolitical restrictions and a course towards technological sovereignty. The key challenges of the industry are considered: a high degree of depletion of existing fields, an increasing share of hard-to-recover reserves (HtRR), exceeding 65 % of the total, as well as critical dependence on imported equipment, software and technologies, reaching 70-95 % in individual segments. Based on the results of scientific and technical analytical work, seven priority areas for the development of the oil and gas sector until 2050 are formulated. Among them: equipment and technologies for well construction and production intensification, metrology of geophysical studies, specialized software for field modeling, monitoring systems, as well as technologies for the development of HtRR using thermochemical and chemical methods of increasing oil recovery. Particular attention is paid to intersectoral end-to-end technologies: bearing and chemical industries, rare earth metals, electronic component base and precision engineering. The need to intensify geological exploration on the Arctic and Far Eastern shelf to ensure production after 2035 is justified. It is shown that the achievement of hydrocarbon production targets – over 500 million tons of oil and more than 850 billion m of ³ gas – is possible only with systematic interaction of the state, business and science within the framework of a unified policy of import substitution and technological sovereignty.

The concept of "hard-to-recover reserves" arises when existing technologies do not correspond to the geological features of the reservoir and the development of such objects is unprofitable. The trinity of concepts: geology – technology – economics is considered in the context of the formation of a conceptual base that allows in the future to administer taxation to stimulate economical oil and gas production.

The origin of the Kama-Kinel system of depressions (KKDS), a system of sub-latitudinal channels that control the position of oil deposits in the Domanik high-carbon formation (DHCF), was considered. The work compares existing hypotheses with data on lithological indicators (tempestites, calciturbidites, spiculites), paleogeographic reconstructions and analogies with Riphean aulacogens. It turned out that the riftogenic factor was secondary. Climate and sedimentary processes came to the fore: storm activity and trade winds. In the shallow basins of the low latitudes of Laurussia, they caused anoxia, accumulation of kerogen, and clinoform filling of depressions. In the axial zones of KKDS, the thickness of the deposits is 30-40 m, which is noticeably lower than the economically justified threshold for multi-stage hydraulic fracturing (about 80 m). Nevertheless, it is precisely to such sections that the new fields put on the balance sheet in 2017-2019. in the Orenburg and Samara regions. The results obtained can be used in the forecast of unconventional oil deposits in high-carbon carbonate-siliceous strata of the VolgaUral province. The formation and evolution of KKDS appears to have been determined by paleohydrodynamics and climate rather than an inherited fault structure.

The paper discusses the relationship between the reservoir properties of the Tournaisian carbonate reservoirs and the structural features of their void space. The purpose of the study was to determine the factors that determine differences in rock permeability at similar porosity values based on a comprehensive core analysis. The object of study was the carbonate deposits of the Tournaisian stage of the Volga-Ural region, represented mainly by wackestones and packstones. A set of methods was used, including standard laboratory determinations of porosity, permeability and associated water saturation, a study of anisotropy of permeability on cubic samples, petrographic study of thin sections and analysis of the structure of the void space according to NMR data. It has been established that the highest filtration and capacitance properties are characterized by packstones, for which a combination of intergranular and intragranular pores connected by capillary channels is typical. Wackestones are characterized by a predominance of microand small-pore space, weak connectivity of pores and, as a result, reduced permeability values, even with comparable porosity. It has been shown that secondary leaching pores play the main role in the formation of reservoir properties of the studied rocks, while cracks have a subordinate value. No pronounced permeability anisotropy was detected in the studied sample. When typing Tournaisian carbonate reservoirs and interpreting well logs, it is necessary to take into account not only the quantitative parameters of porosity, but also the morphology, dimension and hydrodynamic connectivity of the elements of the void space