For highly heterogeneous complex carbonate reef reservoirs, rock typing with respect to depositional conditions, secondary processes, and permeability and porosity relationships is a useful tool to improve reservoir characterization, modeling, prediction of reservoir volume properties, and estimation of reserves. A review of various rock typing methods has been carried out. The basic methods of rock typing were applied to a carbonate reservoir as an example. The advantages and disadvantages of the presented methods are described. A rock typing method based on a combination of hydraulic flow units and the R35 method is proposed. Clustering methods for rock typing are used. The optimum clustering method is identified, and for each rock type, the permeability–porosity relationships are built and proposed for use in the geomodelling stage.

Reef reservoirs are characterised by a complex structure of void space, which is a combination of intergranular porosity, fractures, and vuggy voids distributed chaotically in the carbonate body in different proportions. This causes great uncertainty in the distribution of porosity and permeability properties in the reservoir volume, making field development a complex and unpredictable process associated with many risks. High densities of carbonate secondary alterations can lead to the formation of zones with abnormally high porosity and permeability—high permeability streaks or super-reservoirs. Taking into account super-reservoirs in the bulk of the deposit is necessary in the dynamic modelling of complex-structure reservoirs because it affects the redistribution of filtration flows and is crucial for reservoir management. This paper proposes a method for identifying superreservoirs by identifying enormously high values of porosity and permeability from different-scale study results, followed by the combination and construction of probabilistic curves of superreservoirs. Based on the obtained curves, three probabilistic models of the existence of a superreservoir were identified: P10, P50, and P90, which were further distributed in the volume of the reservoir and on the basis of which new permeability arrays were calculated. Permeability arrays were simulated in a dynamic model of the Alpha field. The P50 probabilistic model showed the best history matching after one iteration.

At present, the study of the oil and gas potential of poorly explored areas of oil and gas basins in the Russian Federation is of great importance due to the possibility of discovering large hydrocarbon accumulations in them. The Vychegda Trough in the north of the Volga–Ural basin is considered to be one of such areas. The research is devoted to the assessment of the oil and gas potential of the Vychegda Trough based on the concept of “petroleum systems”, which is widely used in oil and gas geology. A comprehensive analysis of geological and geophysical, petrophysical and geochemical data was carried out, and modern technologies for studying the oil and gas potential of sedimentary basins were applied: paleotectonic, paleogeographic reconstructions and basin modeling. The results of the research allowed us to determine a sufficiently high potential for the discovery of hydrocarbon accumulations and to identify three potential petroleum systems in the basin section: Riphean, Vendian and Devonian–Permian.

This article considers the deposits of the Late Riphean age, which can potentially be considered as oil and gas source deposits on the East European Platfo

The article considers the deposits of the Late Riphean age, which can potentially be considered as oil and gas source deposits on the East European platform and adjacent folded areas. The data on the interlayers of rocks of the Upper Riphean enriched with organic matter are generalized and systematized. The available data on the characteristics of the organic matter of these rocks are systematized. A comparison of the Upper Riphean sections of this territory is given.

Link for citation: Krivoschekov S.N., Botalov A.N. Structural features and formation conditions of early Famenian riffogenic sediments in the southern part of the Denisov depression of the Timan-Pechora oil and gas province. Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 3, рр. 173-185. In Rus. Relevance. Currently, due to the growth of hard-to-recover resources and hydrocarbon reserves, the study of carbonate rocks of complex structure, in particular the Zadon-Eelets sediments of the Upper Devonian-Tournaisian oil and gas complex of the Denisov depression of the Timan-Pechora oil and gas province, is becoming more relevant. As it is known, the Devonian period in the history of the Timan-Pechora basin is of great importance due to the extensive development of reef sediments, which represent potential zones of oil and gas accumulation. The study of the general features of the structure and the analysis of materials based on the results of macro- and micropetrographic studies of the core will allow reconstructing the facies zonality and paleogeographic conditions of sedimentation of the Zadon-Eelets reef structures as promising objects for the search for oil and gas fields. Aim: study the general features of the structure and lithological and petrographic features of the Zadon-Eelets riphogenic sediments of the Denisov depression, in order to reconstruct their facies zonality, environments and conditions of formation. Objects: Zadon-Elets riffogenic sediments of the Famennian Stage of the Upper Devonian in the southern part of the Denisovsky depression of the Timan-Pechora oil and gas province. Methods: lithological-facies analysis and paleogeographic reconstructions based on the analysis of materials, including a complex of geophysical studies of wells, photographs of columns and sections core, the results of the study of carbonate content rocks, lithological-sedimentological description of the core, as well as photographs and micropetrographic description of the thin rock section. Results. The paper introduces the results of the study of Early Famenian riphogenic sediments, which are potential zones of oil and gas accumulation in the south of the Denisov depression of the Timan-Pechora oil and gas province. The variability of rocks by section and area of the studied area was traced, which made it possible to identify four lithotypes of rocks that are combined into two groups. The material composition of rocks was studied based on the analysis of definitions of carbonate content. The rocks are composed of carbonate minerals – calcite and dolomite – by 93–98 %. Macro- and micropetrographic analysis of structural and textural features of lithotypes using the well-known model of standard facies belts, developed by J. Wilson, allowed reconstructing the facies conditions of sedimentation of the Early Famenian sediments. Rocks were accumulated in three facies zones of the shallow-shelf carbonate platform: an advanced slope, a microbial hill and shallow water, which determined their complex polyfacial structure. Ссылка для цитирования: Кривощеков С.Н., Боталов А.Н. Особенности строения и условия формирования раннефаменских рифогенных отложений южной части Денисовского прогиба Тимано-Печорской нефтегазоносной провинции // Известия Томского политехнического университета. Инжиниринг георесурсов. – 2023. – Т. 334. – № 3. – С. 173-185. Актуальность. В настоящее время ввиду роста трудноизвлекаемых ресурсов и запасов углеводородов более актуальным становится изучение карбонатных пород сложного строения, в частности задонско-елецких отложений верхнедевонско-турнейского нефтегазоносного комплекса Денисовского прогиба Тимано-Печорской нефтегазоносной провинции. Как известно, девонский период в истории Тимано-Печорского бассейна имеет важное значение в связи с обширным развитием рифовых отложений, представляющих собой потенциальные зоны нефтегазонакопления. Изучение общих черт строения и анализ материалов по результатам макро- и микропетрографических исследований керна позволит реконструировать фациальную зональность и палеогеографические обстановки осадконакопления задонско-елецких рифогенных построек как перспективных объектов для поиска залежей нефти и газа. Цель: изучить общие черты строения и литолого-петрографические особенности задонско-елецких рифогенных отложений Денисовского прогиба с целью реконструкции их фациальной зональности, обстановок и условий формирования. Объект: задонско-елецкие рифогенные отложения фаменского яруса верхнего девона южной части Денисовского прогиба Тимано-Печорской нефтегазоносной провинции. Методы:...