The article is devoted to complex (superimposed) petroleum systems considering them as the main object of search for ultra-deep deposits and unconventional resources. Technological progress in geology and oil and gas production in recent decades has been concentrated in two areas. The first one is development of so-called unconventional reservoirs and the second is ultra-deep projects. Previously these two areas had been perceived as alternatives to each other, but they have recently converged because of the fact that unconventional reservoirs at ultra-depths are no longer seen as unprospective. This is mainly due to the fact that areas of high-capacity reservoir development have been established at ultra-deep depths and hypotheses were proposed about the ways of predicting them. In addition to all mentioned above, it has been proved that oil and gas source strata remain productive at depths greater than 9000 meters. All these recent discoveries require appropriate changes in the methods of oil and gas forecasting, including basin modeling, not only at the level of test projects, but also in routine projects. Successful experience in modeling of certain complex systems, carried out in test mode, should be studied and replicated. To optimize exploration work, it is also recommended to consider the geothermal potential of the studied objects.

References

1. Cheng-Zao Jia, Xiong-Qi Pang, Yan Song, Whole petroleum system and ordered distribution pattern of conventional and unconventional oil and gas reservoirs, Petroleum Science, 2023, V. 20, no. 1, pp. 1–19, DOI: http://doi.org/10.1016/j.petsci.2022.12.012

2. Cheng-Zao Jia, Xiong-Qi Pang, Song Yan, Basic principles of the whole petroleum system, Petroleum Exploration and Development, 2024, V. 51(4), pp. 780–794,

DOI: http://doi.org/10.1016/S1876-3804(24)60506-9

3. Tao Hu, Xiongqi Pang, Fujie Jiang. Whole petroleum system theory and new directions for petroleum geology development, Advances in Geo-Energy Research, 2024, V. 11(1), DOI: http://doi.org/10.46690/ager.2024.01.01

4. Zhijun Jin, Hydrocarbon accumulation and resources evaluation: Recent advances and current challenges, Advances in Geoenergy Research, 2023, V. 8(1),

DOI: http://doi.org/10.46690/ager.2023.04.01

5. Lixin Chen et al., An overview of the differential carbonate reservoir characteristic and exploitation challenge in the Tarim Basin (NW China), Energies, 2023, V. 16,

DOI: https://doi.org/10.3390/en16155586

6. Kosenkova N.N., Syngaevskiy P.E., Khafizov S.F., Review of the modern ideas about the hydrocarbon accumulations formation processes at the great depth

(In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2022, no. 5, pp. 6–12, DOI: https://doi.org/10.24887/0028-2448-2022-5-6-12

7. Valenza J., Kortunov P., Alzobaidi S. et al., Origins of pressure dependent permeability in unconventional hydrocarbon reservoirs, Sci Rep., 2023, V. 13(1),

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8. Gaucher E.C., Moretti I., Pélissier N. et al., The place of natural hydrogen in the energy transition: A position paper, Eur. Geol., 2023 V. 55, pp. 5–9,

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9. Jackson O., Lawrence S.R., Hutchinson I.P. et al., Natural hydrogen: sources, systems and exploration plays, Geoenergy, 2024, V. 2(1),

DOI: https://doi.org/10.1144/geoenergy2024-002

10. Wenyang Wang, Pang Xiong, Wang Yaping et al., Critical condition of the depth limit of oil accumulation of carbonate reservoirs and its exploration significance in the lower Ordovician of the Tazhong area in the Tarim basin, American Chemical Society, 2024, DOI: http://doi.org/10.1021/acsomega.3c07793

11. Jianzhong LI, Xiaowan Tao, Bin Bai et al., Geological conditions, reservoir evolution and favorable exploration directions of marine ultra-deep oil and gas in China,

Petroleum Exploration and Development, 2021, V. 48, no. 1, pp. 60–79, DOI: http://doi.org/10.1016/S1876-3804(21)60005-8

12. Juan He, Factors controlling the development of carbonate reservoirs of Ordovician Yingshan formation in the Gucheng area, Tarim Basin, Energy Geoscience, 2023, V. 4, no. 3, DOI: doi.org/10.1016/j.engeos.2022.100147

13. Qiang Ren, Zhen Sun, Hu Wang et al., Characteristics and genesis of carbonate weathering crust reservoirs: A case from the Ma5Member of Ordovician in Gaoqiao Area, Ordos Basin, China, ACS Omega, 2024, V. 9(32), pp. 34329–34338, DOI: https://doi.org/10.1021/acsomega.4c00292

14. Mengying Yang, Xiucheng Tan, Zhaolei Fei et al., Differential evolution and main controlling factors of inner-platform carbonate reservoirs in restricted–evaporative environment: A case study of O2m56 in the Ordos Basin, North China, Minerals, 2025, V. 15(3), DOI: https://doi.org/10.3390/min15030236/

15. Wang Xinpeng, Chen Shuping, Feng Guimin et al., Delaminated fracturing and its controls on hydrocarbon accumulation in carbonate reservoirs of weak deformation regions: A case study of the Yuanba ultra-deep gas field in Sichuan basin, China, Frontiers in Earth Science, 2022, V. 10, DOI: http://doi.org/10.3389/feart.2022.884935

16. Malysheva S.V., Vasil'ev V.E., Komissarov D.K. et al., Modeling of Bazhenov formation of Western Siberia as an unconventional hydrocarbon source (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2012, no. 12, pp. 14-17.

17. Guangyou Zhu, Milkov A., Li Jingfei et al., Deepest oil in Asia: Characteristics of petroleum system in the Tarim basin, China, Journal of Petroleum Science and Engineering, 2021, V. 199, DOI: http://doi.org/10.1016/j.petrol.2021.108246

18. Kiswaka E.B., Mshiu E.E., Mafia deep basin: basin development and petroleum system elements, J. Sediment. Environ., 2023, no. 8, pp. 153–173,

DOI: https://doi.org/10.1007/s43217-023-00128-8

19. Li Guoyu, World atlas of oil and gas basins, Wiley-Blackwell, 2011, 496 p., DOI: https://doi.org/10.5860/choice.48-6656

20. Xiongqi Pang, Chengzao Jia, Kun Zhang et al., The depth limit for the formation and occurrence of fossil fuel resources, Earth System Science Data Discussions, 2019, http:// doi.org/10.5194/essd-2019-72

The article considers the current problem of hydrocarbon deposits search and forecasting in the conditions of depletion of traditional fields. Examples of successful discoveries in the Gulf of Mexico, on the northern coast of Alaska and in the Tarim and Sichuan basins are presented, which confirms the high prospects of ultra-deep horizons (6000 m and more) as a source of replenishment of the resource base. However, the key issue remains the preservation of the filtration-capacitive properties of reservoirs at such depths. The article focuses on the importance of lineaments that can be identified using aerial and space images. Lineaments, which are rectilinear relief elements, are associated with breaks and fracturing, and their study enables to obtain a continuous image of the geological structure. Particular attention is paid to regular systems of lineaments, known as the «regmatic network», which have a regular orientation and can serve as an important indicator for forecasting the oil and gas content of the subsoil. The article emphasizes the need for further research in this area for the efficient use of resources at great depths. The deciphered systems of lineaments of the Tarim and Sichuan oil and gas basins are considered. The geometric features of the lineament network and their statistical characteristics are revealed.

References

1. Iskaziev K.O., Syngaevskiy P.E., Khafizov S.F., Deep oil (In Russ.) Vestnik neftegazovoy otrasli Kazakhstana = Kazakhstan journal for oil & gas industry, 2020, no. 3(4), pp. 3−19, DOI: http://doi.org/10.54859/kjogi95639

2. Kuandykov B.M., Syngaevskiy P.E., Khafizov S.F., Formation and preservation of reservoirs at great depth (In Russ.), Vestnik neftegazovoy otrasli Kazakhstana = Kazakhstan journal for oil & gas industry, 2022, V. 4, no. 2, pp. 12-19, DOI: http://doi.org/10.54859/kjogi100605

3. Kosmogeologiya SSSR (Cosmogeology of the USSR): edited by Bryukhanov V.N., Mezhelovskiy N.V., Moscow: Nedra Publ., 1987, 240 p.

4. Sadovskiy M.A., On the block structure of the Earth's lithosphere (In Russ.), Uspekhi fizicheskikh nauk, 1985, V. 147, pp. 421–422.

5. Lopatin D.V., Geomorphologic indication of deep ore-bearing structural forms (In Russ.), Vestnik Moskovskogo Universiteta. Seria 5, Geografia = Moscow University Bulletin. Series 5, Geography, 2011, no. 1, pp. 28–35.

6. Lopatin D.V., Lineament tectonics and giant deposits (In Russ.), Issledovanie Zemli iz kosmosa, 2002, no. 2, pp. 77–90.

7. Belozerov V.B., Planar fracturing and development of petroleum reservoirs (In Russ.), Izvestiya Tomskogo politekhnicheskogo universiteta = Bulletin of the Tomsk Polytechnic University. Geo Assets Engineering, 2015, V. 326, no. 1, pp. 6–13.

8. Miloserdova L.V., Dantsova K.I., Experience of teaching the discipline “Aerospace methods in Oil and Gas Geology” at Gubkin Russian State University of Oil and Gas (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2022, no. 5, pp. 39-43, DOI: https://doi.org/10.24887/0028-2448-2022-5-39-43

As part of the research, volumetric basin modeling of hydrocarbon systems of the Kurshskaya depression was carried out, and the history of its geological evolution was studied. The time of entering of oil and gas source deposits in the main oil formation zone and the beginning and volumes of intensive hydrocarbon generation are determined, the position of oil and gas source rocks in the hydrocarbon generation zones is shown at the present time. The main elements of hydrocarbon systems and the processes occurring in them are described. The main tectonic eras in the geological history of the formation of the Kurshskaya depression were identified and described. An assessment of the prospects of oil and gas potential is given. The main source of hydrocarbons in the sedimentary part of the Kurshskaya depression are rocks of the lower division of the Cambrian system (Aischaiskaya series) and the Llandoverian division of the Silurian system. The generation of hydrocarbons began in the Early Devonian and still continues to this day. The generated hydrocarbons accumulate in structural traps associated with rocks of the Deymenskaya formation of the Cambrian system. The main prospects are related to the regional reservoir of the Middle Cambrian age. The conducted basin modeling confirmed the oil and gas potential of the territory and also enabled to compare the results with the structures identified as a result of seismic exploration work.

References

1. Kanev S., Margulis L., Bojesen-Koefoed J.A. et al., Oils and hydrocarbon source rocks of the Baltic sineclyse, Oil & Gas Journal, 1994, July, pp. 69–73.

2. Aver'yanova O.Yu., Petroleum systems of some European sedimentary basins (In Russ.), Neftegazovaya geologiya. Teoriya i praktika, 2015, V. 10, no. 2.

3. Zaripova R.R., Dorofeev N.V., An approach to forecasting prospective oil and gas structures based on the analysis of generation and migration processes of the system (In Russ.), Neftepromyslovoe delo, 2021, no. 6(630), pp.. 17–21, DOI: https://doi.org/10.33285/0207-2351-2021-6(630)-17-21

4. Otmas A.A. (Senior), Volchenkova T.B., Bogoslovskiy S.A., Silurian pelitic layers in Kaliningrad region - A possible target for hydrocarbon prospecting (In Russ.), Neftegazovaya geologiya. Teoriya i praktika, 2013, V. 8, no. 3, DOI: http://doi.org/10.17353/2070-5379/30_2013

5. Bazhenova T.K., Shapiro A.I., Vasil'eva V.F., Otmas A.A. (Senior), Geochemistry of organic matter and hydrocarbon generation in the Lower Silurian deposits of the Kaliningrad region (In Russ.), Neftegazovaya geologiya. Teoriya i praktika, 2012, V. 7, no. 2.

6. Desyatkov V.M., Otmas A.A., Siryk S.I., Geochemistry of organic matter and hydrocarbon generation in the lower Silurian deposits of the Kaliningrad region Neftegazonosnost' Kaliningradskogo regiona (In Russ.), Geologiya, geofizika i razrabotka neftyanykh i gazovykh mestorozhdeniy, 2006, no. 8, pp. 24–30.

7. Kosakowski P., Zakrzewski A., Waliczek M., Ordovician and Silurian formations of the Baltic syneclise (NE Poland): An organic geochemistry approach, Lithosphere, 2022, no. 1, DOI: https://doi.org/10.2113/2022/7224168

The Vasyugan formation in the southern part of the West Siberian oil and gas province is one of the primary oil and gas complexes. In the study area, confined to the tectonic zone of the junction of the Yugansk megadepression with the Nizhnevartovsk arch, the J11 horizon is of greatest interest for geological exploration and replenishment of the resource base. Due to the polyfacial structure of the studied reservoir and the presence of various hydrodynamic barriers that affect the nature of the formation saturation and separate the structural elements of the III-IV orders, to which the oil deposits are confined, a regional conceptual geological model was developed. The features and evolution of sedimentation of the late Oxfordian paleodelta system are specified by means of integration of seismic and well data. Tracing the migrational transgressive-regressive events enabled to identify the facies features of the structure and to classify and rank the sand objects of the J11 horizon. Sand facies of delta mouth bars, distribution channels and accretionary complexes, and transgressive barrier island systems were established and mapped. The significance of the regionally formed structural patterns of the J11 horizon is shown in the development of a program for exploration drilling. The proposed approach to conceptual modeling can be applied to similar geological objects.

References

1. Polyukh N.A., Buzilov A.S., Evdokimov I.V. et al., An integrated approach to seismogeological modeling and facies analysis of complex objects by the example of the JV11 horizon of the Vasyugan formation (In Russ.), Geofizika, 2024, no. 3, pp. 21–28, DOI: https://doi.org/10.34926/geo.2024.91.35.003

2. Belozerov V.B., Role of sedimentation models in electrofacial analysis of terrigenous deposits (In Russ.), Izvestiya Tomskogo politekhnicheskogo universiteta = Bulletin of the Tomsk Polytechnic University, 2011, V. 319, no. 1, pp. 116-123.

3. Muromtsev V.S., Elektrometricheskaya geologiya peschanykh tel – litologicheskikh lovushek nefti i gaza (Electrometric geology of sand bodies - lithological traps of oil and gas), Leningrad: Nedra Publ., 1984, 260 p.

4. Shurygin B.N., Pinus O.V., Nikitenko B.L., Sequence-stratigraphic interpretation of the Callovian and Upper Jurassic (Vasyugan horizon) of the southeast of West Siberia (In Russ.), Geologiya i geofizika, 1999, V. 40, no. 6, pp. 843–862.

5. Beyzel' A.L., Changes in the intensity of sediment removal are the main factor in the formation of sedimentary complexes (based on the Jurassic of Western Siberia) (In Russ.), Geologiya, geofizika i razrabotka neftyanykh i gazovykh mestorozhdeniy, 2006, no. 5–6, pp. 34–44.

6. Yan P.A., Vakulenko L.G., Burleva O.V. et al., Obstanovki formirovaniya bat-verkhneyurskikh otlozheniy Zapadno-Sibirskogo basseyna: prostranstvenno-vremennye zakonomernosti i faktory evolyutsii (Sedimentary environments of Bathonian — Upper Jurassic deposits of the Western-Siberian basin: Spatial-temporal patterns and evolution factors), Collected papers “Novye vyzovy fundamental'noy i prikladnoy geologii nefti i gaza – XXI vek” (New challenges of fundamental and applied geology of oil and gas – 21st century), 2021, pp. 57–60.

The main fields of the Uzen-Zhetybai stage have a high degree of depletion of hydrocarbon reserves associated with deposits of Mesozoic age. In this regard, the search for new deposits to replenish the raw material base is becoming an important task for the studied region. In addition to the Meso-Cenozoic part of the section, sediment productivity was also established in the underlying Paleozoic complexes, for example, the Oymasha field. Therefore, the expansion of promising territories and the discovery of new accumulations of hydrocarbons by studying deep-lying Paleozoic sediments using the latest data are becoming more important at the moment. An assessment of the processes of generation, possible migration and subsequent filling of potential structural traps was carried out; the development of drainage areas and their spatiotemporal relationship with the hydrocarbon generation zones were also studied. Various scenarios of the functioning of hydrocarbon systems are shown – the presence of source rocks (SR) only in Mesozoic sediments, as well as scenarios that take into account the influence of the proposed Paleozoic SR, considered using the analogy of the sediments on the eastern side of the Caspian Basin, and the influence of additional local warming of the SR. The presence of only Mesozoic SR does not enable to achieve the saturation observed according to actual data, including the phase composition.

References

1. Miletenko N.V., Fedorenko O.A., Atlas litologo-paleogeograficheskikh, strukturnykh, palinspasticheskikh i geoekologicheskikh kart Tsentral’noy Evrazii (Atlas of lithological-paleogeographic, structural, palinspastic and geoecological maps of Central Eurasia), Almaty: Publ. of Research Institute of Natural Resources YuGGEO,

2002, 26 p.

2. Galushkin Yu.I., Modelirovanie osadochnykh basseynov i otsenka ikh neftegazonosnosti (Simulation of sedimentary basins and assessment of their oil and gas potential), Moscow: Nauchnyy mir Publ., 2007, 456 p.

3. Burnham A.K., Global chemical kinetics of fossil fuels: How to model maturation and pyrolysis, Springer International Publishing, 2017, 315 p.,

DOI: https://doi.org/10.1007/978-3-319-49634-4

4. Burnham A.K., Braun R.L., Global kinetic analysis of complex materials, Energy Fuels, 1999, V. 13, no. 1, pp. 1-22, DOI: https://doi.org/10.1021/ef9800765

5. Fomin A.N., Katagenez organicheskogo veshchestva i neftegazonosnost’ mezozoyskikh i paleozoyskikh otlozheniy Zapadno-Sibirskogo megabasseyna (Catagenesis of organic matter and oil and gas potential of Mesozoic and Paleozoic deposits of the West Siberian megabasin), Novosibirsk: Publ. of Institute of Petroleum Geology and Geophysics named after A.A. Trofimuk Siberian Branch of the Russian Academy of Sciences, 2011, 331 p.

6. Kalmykov G.A., E.V. Karpova, N.S. Balushkina et al., Gidrotermal’no-metasomaticheskaya prorabotka osadochnogo chekhla kak odin iz faktorov formirovaniya zalezhey nefti i gaza (Hydrothermal-metasomatic processing of sedimentary cover as one of the factors in the formation of oil and gas deposits), Collected papers “Fundamental’nye, global’nye i regional’nye problemy geologii nefti i gaza” (Fundamental, global and regional problems of oil and gas geology), Proceedings of All-Russian scientific conference dedicated to the 90th anniversary of the birth of Academician of the Russian Academy of Sciences A.E. Kontorovich, 2024, pp. 79–81.

7. Latypova M.R., Prokof’ev V.Yu., Balushkina N.S. et al., Fluid inclusions geochemical characteristics as indicators of the organic matter transformation degree in Jurassic sediments of the Em-Ega crest (Krasnoleninsky arch, Western Siberia) (In Russ.), Vestnik Moskovskogo universiteta. Seriya 4: Geologiya = Moscow University Bulletin. Series 4. Geology, 2023, no. 2, pp. 79–92, DOI: https://doi.org/10.55959/MSU0579-9406-4-2023-63-2-79-92

The Baltic region is one of the most studied oil basins in Russia, where fields are currently being developed, but there are a number of unresolved issues concerning the evolution of the sedimentary section and the formation of reservoirs of the Cambrian-Ordovician oil complex. The purpose of this work is to perform basin modeling to build digital models of the evolution of the sedimentary basin, as well as the generation, migration and accumulation of hydrocarbons within the Baltic oil region. To construct a correct basin model, parameters such as the lithological composition of rocks, geochemical characteristics of oil and gas source rocks, and thermal characteristics of the section were determined. As a result of basin modeling, the most probable volumetric models of generation, migration and accumulation of hydrocarbons in the studied section were obtained, which enables to trace the stages of the beginning of oil and gas generation, assess the maturity of oil and gas source rocks, and trace the patterns of distribution of hydrocarbon deposits over the area of the studied region. The selected parameters and boundary conditions are correct, and the obtained results are in good coherence with the drilling data and can serve as a basis for more detailed basin modeling. The modeling results enabled to confirm the oil potential of the study area at the regional level, as well as to determine priority areas for further geological exploration work.

References

1. Musikhin K.V., Usloviya formirovaniya i sokhraneniya kollektorskikh svoystv porod i zalezhey uglevodorodov nizhne-sredneyurskikh otlozheniy Frolovskoy megavpadiny (Conditions of formation and preservation of reservoir properties of rocks and hydrocarbon deposits of the Lower-Middle Jurassic deposits of the Frolovskaya megadepression): thesis of candidate of geological and mineralogical science, Moscow, 2020.

2. Otmas A.A. (Senior), Volchenkova T.B., Bogoslovskiy S.A., Silurian pelitic layers in Kaliningrad region - A possible target for hydrocarbon prospecting (In Russ.), Neftegazovaya geologiya. Teoriya i praktika, 2013, V. 8, no. 3, DOI: http://doi.org/10.17353/2070-5379/30_2013

3. Otmas A.A. (Senior), Margulis L.S., Otmas A.A., Petroleum potential prospects of the Baltic sea shelf (In Russ.), Neftegazovaya geologiya. Teoriya i praktika, 2017, V. 12, no. 1, DOI: https://doi.org/10.17353/2070-5379/4_2017

4. Levashkevich V.G., Zakonomernosti
raspredeleniya geotermicheskogo polya okrain Vostochno-Evropeyskoy platformy
(Barentsevomorskiy i Belorussko-Pribaltiyskiy regiony) (Patterns of
distribution of the geothermal field of the margins of the East European
platform (Barents Sea and Belarusian-Baltic regions)): thesis of doctor of
geological and mineralogical science, Moscow: MSU, 2005.

The article describes the methodological features of performing sedimentation modeling in the DionisosFlow™ software, as well as the results of a study on the subsalt deposits of the northern side of the Pre-Caspian depression. The input parameters for the model are described. Modeling in the DionisosFlow™ program enables to obtain detailed forecast maps of facies with high vertical resolution. The method is based on consideration of the accommodation zone, the influx of sedimentary material and the formation of carbonates and precipitation transfer based on the diffusion equation. Based on the criteria of sedimentation conditions, the probable position of facies within the simulated area is determined. The results obtained reflect the main stages of formation of the Devonian-Lower Permian sedimentary cover of the Caspian syneclise. Throughout the history of its development, the Central Caspian depression represented the most submerged parts of the sedimentation basin, where deep-sea sedimentation facies were concentrated and the farthest from the sources of demolition. Carbonate platforms and reef massifs are developed in the side zones. Powerful paleochannel systems ensured the flow of detrital material deep into the depression and formed a clinoform complex. The paper presents maps of the distribution of facies conditions into the main stages of sedimentary cover formation, which can be used for further basin modeling within the northern side of the Pre-Caspian depression.

References

1. Snedden J.W., Liu Ch., A compilation of Phanerozoic sea-level change, coastal onlaps and recommended sequence designations, AAPG Search and Discovery, 2010,

V. 40594, no. 3

2. Abilkhasimov Kh.B., Osobennosti formirovaniya prirodnykh rezervuarov paleozoyskikh otlozheniy Prikaspiyskoy vpadiny i otsenka perspektiv ikh neftegazonosnosti (Features of the formation of natural reservoirs of the Paleozoic sediments of the Caspian basin and assessment of the prospects of their oil and gas potential), Moscow: Publ. of Academy of Natural Sciences, 2016, 244 p.

3. Zhemchugova V.A., Makarova E.Yu., Naumchev Yu.V. et al., Carbonate reservoirs of subsalt deposits of the Caspian syneclise (In Russ.), Georesursy, 2017, Special issue. Part 2, pp. 194–207, DOI: http://doi.org/10.18599/grs.19.20

4. Konovalenko S.S., Paleogeomorfologiya yugo-vostoka Russkoy plity (Orenburgskaya oblast') ot rifeya do turne v svyazi s poiskami nefti i gaza (Paleogeomorphology of the south-east of the Russian plate (Orenburg region) from the Riphean to the Tournaisian in connection with the search for oil and gas): thesis of doctor of geological and mineralogical science, Samara, 1999.

5. Schlager W., The paradox of drowned reefs and carbonate platforms, Geological Society of America Bulletin, 1981, V. 92, no. 4, pp. 197–211,

DOI: https://doi.org/10.1130/0016-7606(1981)92%3C197:TPODRA%3E2.0.CO;2

6. Gibshman N.B., Stratigrafiya i fatsial'nye osobennosti dokungurskikh otlozheniy nizhney permi severnoy bortovoy zony Prikaspiyskoy vpadiny po faune foraminifer (Stratigraphy and facies features of the pre-Kungurian deposits of the Lower Permian of the northern marginal zone of the Caspian Basin based on foraminifera fauna), In: Geologiya i neftegazonosnost' podsolevogo paleozoya Prikaspiyskoy sineklizy (Geology and oil and gas potential of the pre-salt Paleozoic Caspian syneclise), Proceedings of Gubkin Institute, 1983, V. 170, pp. 5−12.

7. Lyapunov Yu.V., Strelkov A.A., Oil and gas
prospects of Paleozoic rocks of Pogadaevo-Ostafievskiy sag and neighbouring
territories of Precaspian depression (In Russ.), Trudy RGU nefti i gaza imeni
I.M. Gubkina = Proceedings of Gubkin University, 2009, no. 3(256), pp. 13–21.

Salt formations have a significant impact on the temperature distribution within the sedimentary cover of oil and gas basins. Having a high thermal conductivity, salts have a cooling effect on subsalt deposits thereby increasing the depth of catagenesis. In addition, evaporite layers are subject to visco-plastic flow, which leads to the formation of large salt diapirs in some parts of the basin and zones without halogen deposits in others. Therefore, when constructing a basin model, it is important to correctly reproduce all the stages of formation of salt sediments, as well as their subsequent transformations caused by the salt tectonics. The Early Permian salt deposits of the Pre-Caspian basin act as one of the leading factors in the formation of the territory's oil and gas potential. Currently, there is no consensus on the conditions for the formation of such a large thickness salt layer. Some scientists claim the accumulation of salt in a deep-sea basin as a result of the penetration of highly mineralized solutions into a semi-isolated basin within the Pre-Caspian depression. Others suggest sedimentation in a shallow basin at the bottom of the depression. Different water depths during the formation of salt deposits imply different temperatures and sedimentation pressures, which in turn can affect the hydrocarbon systems operating in the Pre-Caspian basin. In this work, the authors attempted to model various scenarios for the formation of the Early Permian complex and compare the results of the catagenetic maturity of subsalt source rocks.

References

1. Belenitskaya G.A., Salts and naphthides: global spatial and kinetic relationships (In Russ.), Regional'naya geologiya i metallogeniya, 2014, no. 59, pp. 97–112.

2. Antipov M.P., Bykadorov V.A., Volozh Yu.A. et al., Stratigraphy and seismostratigraphy of the Permian Evaporite Formation in the salt-producing province of the Caspian Region: Problems and solutions (In Russ.), Stratigrafiya. Geologicheskaya korrelyatsiya, 2023, V. 31, no. 2, pp. 40–58, DOI: http://doi.org/10.31857/S0869592X23020011

3. Komissarova I.N., Osnovnye cherty drevnego i sovremennogo solenakopleniya na territorii Prikaspiyskoy vpadiny (The main features of ancient and modern salt accumulation in the territory of the Caspian Depression), In: Novye dannye po geologii solenosnykh basseynov Sovetskogo Soyuza (New data on the geology of salt basins of the Soviet Union), Moscow: Nauka Publ., 1986, pp. 171–180.

4. Emelianenko O.A., Delengov M.T., Ilmukova E.V. et al., Basin modelling of hydrocarbon systems of Pre-Caspian depression (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2023, No. 5, pp. 21-25, DOI: https://doi.org/10.24887/0028-2448-2023-5-21-25

5. Antipov M.P., Bykadorov V.A., Volozh Yu.A. et al., Orenburgskiy tektonicheskiy uzel: geologicheskoe stroenie i neftegazonosnost' (Orenburg tectonic knot: geological structure and oil and gas potential): edited by Volozh Yu.A., Parasyn V.S., Moscow: Nauchnyy mir Publ., 2013, 291 p.

The article explores the sandstone horizon located in the upper part of the Blinovskaya formation section in the Maikop area, near the hydroelectric dam. As a result of the discharge of water into the bypass channel of the hydroelectric dam, a section of the Belaya riverbed was exposed, which enabled to study sandstones with a thickness of up to 50 m and consisting of layers of various thicknesses alternating with marl layers. This sandstone horizon is underlain by the Middle Sarmatian lake sediments and belongs to the transgressive stage of development of the Late Sarmatian Sea. The 1D-24 sample was taken from the middle part of the horizon and demonstrated an argose composition with a high content of quartz and feldspar, as well as carbonate inclusions. The paper presents the results of U–Pb dating of dZr grains from Upper Sarmatian sandstones, which indicate the predominance of the «northern» source of detrital material demolition, specific to Eastern European region. The absence of significant U–Pb dating from the Early-Middle Jurassic and the presence of Mesoproterozoic dating indicate differences in the provenance signal compared to the «southern» source. During the transgression of the Late Sarmatian Sea, when the studied sandstones were formed, detrital material came from the north, while no signs of the Greater Caucasus orogen being a source of detrital matter in the Late Sarmatian basin were identified. The rocks of the pre-Alpine structural floors of the Greater Caucasus were not represented on the surface in the Late Sarmatian.

References

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no. 9, pp. 78‒84, DOI: http://doi.org/10.24887/0028-2448-2023-9-78-84

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(In Russ.), Geotektonika = Geotectonics, 2018, V. 52, no. 3, pp. 331-345, DOI: https://doi.org/10.7868/S0016853X18030037

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(In Russ.), Byulleten’ Moskovskogo obshchestva ispytateley prirody. Otdel geologicheskiy, 2002 a, V. 77, no. 1, pp. 47‒59.

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The article considers the results of reconstructing the history of oil and gas formation and accumulation in the Tersko-Caspian trough based on volumetric modeling of hydrocarbon systems. The oil and gas bearing systems of the Central and Eastern Ciscaucasia are characterized, and the factors influencing their formation are considered. The main foci of generation at each stratigraphic level were identified based on existing and assumed oil and gas source rocks. It is worth noting their high maturity and depletion in the central parts of the Tersko-Caspian trough, the on-board zones are characterized by low values of these parameters and continue to actively generate hydrocarbons. The oil and gas deposits in the reservoirs of the structural type were formed due to lateral and vertical fluid migration from different source rocks. The coincidence in terms of most of the discovered gas and oil fields with the accumulations obtained in the process of three-dimensional modeling indicates a good convergence of the results with the actual data. As a result of the modeling, the most promising local structures with possible hydrocarbon deposits in the most promising stratigraphic complexes were outlined. The clinoform complex of Maikop, which is the least studied by seismic exploration due to the orientation of geological exploration to deeper reflecting horizons, is considered one of the objects of possible reserve increment. The results obtained based on the results of two-dimensional modeling indicate favorable conditions for the generation, migration, accumulation and preservation of hydrocarbons in non-structural traps.

References

1. Lebed'ko G.I., Kuzin A.M., Geologo-geofizicheskaya interpretatsiya flyuidonosnykh zon zemnoy kory Severnogo Kavkaza (Geological and geophysical interpretation of fluid-bearing zones of the earth's crust of the North Caucasus), Rostov-na-Donu: Publ. of Southern Federal University, 2010, 302 p.

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4. Yandarbiev N.Sh., Fadeeva N.P., Kozlova E.V., Naumchev Yu.V., Khadum Formation of Pre-Caucasus region as potential source of oil shales: geology and geochemistry (In Russ.), Georesursy, 2017, Special Issue, Part 2, pp. 208–226.

5. Palaeogeographic atlas of the shelf regions of Eurasia for the Mesozoic and Cenozoic. Vol. 2. Maps: edited by Alekseev M.N., Robertson Group plc, UK & Geological Institute, Academy of Sciences, USSR, 1992, 104 p.

6. Babina E.O., Mordasova A.V., Stupakova A.V. et al., Sedimentation of the Oligocene-lower Miocene clinoforms of the Maikop formation in the Eastern and Central Pre-Caucasus region as a key criteria for reservoir exploration (In Russ.), Georesursy, 2022, V. 24, pp. 192–208, DOI: https://doi.org/10.18599/grs.2022.2.18

The article presents the results of geochemical studies of bottom sediment samples which were collected in the license areas of Rosneft Oil Company on the Laptev Sea shelf. In order to identify gas anomalies that may indicate hydrocarbon migration from oil and gas deposits, a set of laboratory studies was performed to study the component composition of gases using the method of equilibrium concentrations (Head-Space Analysis - HAS) and the isotopic composition of carbon in gas components was determined using the GC-C-IRMS method (mass spectrometry of isotopic ratios using a gas chromatograph). Based on the results of complex geochemical studies, evidence was obtained of migration of deep fluids into the bottom sediments. This is indicated by the wide variability of the isotopic composition of methane carbon (-73-102 ‰), which is due to the mixing of thermogenic isotopically heavy (-30-50 ‰) methane with microbial gas (-100-110 ‰), the presence of methane homologues (C2-C5) in the degassing gases, as well as the detection of isotopically heavy (thermogenic) ethane. The conducted studies are good indicators of the presence of oil-and-gas source rocks in the sedimentary section of the Laptev Sea, which confirms the idea of the significant oil and gas potential of the offshore area.

References

1. Yashin D.S., Kim B.I., Geochemical features of oil and gas potential of eastern Arctic shelf of Russia (In Russ.), Geologiya nefti i gaza, 2007, no. 4, pp. 25–29.

2. Evdokimova N.K., Yashin D.S., Kim B.I., Hydrocarbon potential of sedimentary cover deposits of offshore east Arctic seas of Russia (Laptev, East Siberian and Chukotsk) (In Russ.), Geologiya nefti i gaza, 2008, no. 2, pp. 3–12.

3. Malyshev N.A., Borodulin A.A., Obmetko V.V. et al., Formirovanie UV-sistem i prognoz neftegazonosnosti shel’fa morya Laptevykh (Formation of hydrocarbon systems and forecast of oil and gas potential of the Laptev Sea shelf), Proceedings of conference “Neft’ i gaz arkticheskogo shel’fa” (Arctic shelf oil and gas), Murmansk, 12–14 November 2008, Murmansk: Publ. of MMBI RAS, 2008, pp. 32‒37.

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9. Petukhov A.V., Starobinets I.S., Osnovy teorii geokhimicheskikh poley uglevodorodnykh skopleniy (Fundamentals of the theory of geochemical fields of hydrocarbon accumulations), Moscow: Nedra Publ., 1993, 332 p.

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(In Russ.), Geologiya i geofizika, 2020, no. 4, pp. 560–585, DOI: https://doi.org/10.15372/RGG2019150

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Most of the Ciscaucasia oil fields are in the final stage of development or have been completely developed. The reduction in the fund of economically viable production facilities predetermines the need to increase the efficiency of additional development and exploration of fields. The search for missed hydrocarbon deposits is currently relevant for this region. For the first time in more than 20 years, employees of PJSC NK Rosneft and its subsidiaries Rosneft-NTC LLC and Grozneftegaz JSC have discovered and brought into production two oil deposits in a new stratigraphic range  the Lower Maykop deposits. The non-target status of the Maykop deposits, combined with extremely difficult drilling conditions and a significant amount of lost data within the Terek-Caspian trough, predetermined its low geological and geophysical exploration. This, along with the absence of reliable analogous deposits in the Eastern Ciscaucasia, led to the need to apply a non-standard integrated approach to interpretation of petrophysical well logging model and assessing the calculation parameters within the framework of calculating hydrocarbon reserves. The solution of the problems is based on the creation of a data matrix with characteristics for the Maykop deposits of the North Caucasian oil and gas region, their ranking by the degree of compliance of the parameters and maximum relevance of the geological parameters of the reserves calculation object. This, along with the involvement of additional information, enabled to calibrate the well logging interpretation technique, substantiate the adopted boundary values, and establish objective probabilities of the range of their change.

References

1. Beluzhenko E.V., Golovanov M.P., Dontsova O.L. et al., Maykopskie (oligotsen-nizhnemiotsenovye) otlozheniya zapadnoy i tsentral'noy chastey Severnogo Kavkaza (Maikop (Oligocene-Lower Miocene) deposits of the western and central parts of the North Caucasus), Krasnodar: Publ. of Kuban State University, 2021, 507 p.

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Yatsenko G.G., Moscow – Tver: Publ. of VNIGNI, 2003, 261 p.

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The results of studies of a large stratigraphic unconformity at the base of Cretaceous deposits in the territories of Western Siberia are presented. Due to new data obtained during the work to estimate the oil and gas potential of the Cretaceous strata, the volume and area distribution of stratigraphic unconformity in the section of Cretaceous deposits in the interior of Western Siberia were pointed. The stratigraphic volume of sediments missing in the section as a result of their non-accumulation/erosion in the pre-Valanginian time was estimated. Based on new data on biostratigraphy, magnitostratigraphy, sedimentology, and the results of geophysical studies of wells, a partial or complete absence of Ryazan stage sediments in the territory of the Pur-Taz interfluve was established. A method for detecting signs of stratigraphic unconformity in deep layers of the Western Siberia sedimentary basin is proposed. It is established that the occurrence of the pre-Valanginian unconformity is associated with a regressive sequence of facies. The formation of the layer overlying the unconformity surface reflects the transgressive stage of sedimentation. The stratigraphic position of the formation bottom changes within the age interval of accumulation of the transgressive formation, which is recorded by stratigraphic methods. Since the age interval of forming of the transgressive formation is much smaller than the volume of stratigraphic unconformity, the surface can be considered as quasi-isochronous. In accordance with the requirements of the Stratigraphic Code of Russia, the presence of stratigraphic unconformity is proposed to be reflected in regional stratigraphic schemes.

References

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2. Stratigraficheskiy kodeks Rossii (Stratigraphic Code of Russia), St. Petersburg, Publ. of Karpinsky Russian Geological Research Institute, 2019, 96 p.

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6. Nezhdanov A.A., Kulagina S.F., Gerasimova E.V., The influence of late cimmerian folding upon stratification of early neocomian deposits in West Siberia (In Russ.),

Ekspozitsiya Neft' Gaz, 2017, no. 7(60), pp. 18–22.

7. Marinov V.A., Agalakov S.E., Dubrovina L.A. et al., Markiruyushchie gorizonty melovoy sistemy Zapadnoy Sibiri kak osnova regional'noy korrelyatsii (Marking horizons of the Cretaceous system of Western Siberia as a basis for regional correlation), Collected papers “Melovaya sistema Rossii i blizhnego zarubezh'ya: problemy stratigrafii i paleogeografii” (Cretaceous system of Russia and neighboring countries: problems of stratigraphy and paleogeography), Proceedings of XII All-Russian Conference, 7-11 October 2024, Yuzhno-Sakhalinsk: Indigo Publ., 2024, pp. 143–146.

8. Potapova A.S., Vilesov A.P., Chertina K.N. et al., Signs of the subaeral exposition at the border of Abalak and Tutlim (Bazhenov) suite (In Russ.), Geologiya, geofizika i razrabotka neftyanykh i gazovykh mestorozhdeniy, 2018, no. 11, pp. 13–19, DOI: https://doi.org/10.30713/2413-5011-2018-11-13-19

9. Lapina L.V., Lebedev M.V., Levkovich O.S. et al., The Yanovstan formation of Western Siberia: internal structure and results of zoning (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2024, no. 8, pp. 48–53, DOI: https://doi.org/10.24887/0028-2448-2024-8-48-53

10. Rozbaeva G.L., Agalakov S.E., Marinov V.A. et al., Results of stratigraphic breakdown of Lower Cretaceous deposits in Payakha oil and gas accumulation zone (West Siberian Yenisei-Khatanga petroleum region) (In Russ.), Geologiya nefti i gaza, 2025, no. 2, pp. 37–51, DOI: https://doi.org/10.47148/0016-7894-2025-2-57-71

11. Aleynikov A.N., Kutsman A.N., Biostratigrafiya nizhnekhetskoy svity Vankorskogo neftegazovogo mestorozhdeniya (Biostratigraphy of the Nizhnekhetskaya suite of the Vankor oil and gas field), Collected papers “Regional'naya geologiya. Stratigrafiya i paleontologiya fanerozoya Sibiri” (Regional geology. Stratigraphy and paleontology of the Phanerozoic of Siberia),. Novosibirsk: Publ. of SNIIGGiMS, 2009, pp. 130–141.

12. Marinov V.A., Kislukhin I.V., Merkulov V.P. et al., Kharakteristika pogranichnykh yursko-melovykh otlozheniy Bol'shekhetskoy strukturnoy terrasy (Zapadnaya Sibir') (Characteristics of the Jurassic-Cretaceous boundary deposits of the Bolshekhetskaya structural terrace (Western Siberia)), Collected papers “Melovaya sistema Rossii i blizhnego zarubezh'ya: problemy stratigrafii i paleogeografii” (Cretaceous system of Russia and neighboring countries: problems of stratigraphy and paleogeography), Proceedings of IX All-Russian Conference, Belgorod, 17-21 September 2018, Belgorod: POLITERRA Publ., 2018, pp. 178–182.

In terms of chemical properties, limestone is an unstable rock and is susceptible to dissolution by water. Secondary voids have complex unpredictable geometry, heterogeneity of distribution, variety of scales and can create a useful volume for hydrocarbon accumulation. The main object of study is the carbonate reservoir of object A of oil field X, located within the Timan-Pechora oil and gas bearing province. It was established that the Famen deposits can be divided into two main zones in terms of sedimentation conditions: the barrier zone in the south and the back barrier in the north. The back barrier is dominated by a matrix type of reservoir with no faulting, fracturing and karst. The model, which takes into account the porosity cut-off reservoir, does not correspond to historical data. To identify cavernous intervals, drilling data (drilling mud losses), formation microimager (FMI) and production liquid tool were analyzed. In the interwell space, karst (after upscaling karst curve to grid cells) is distributed by Sequential Indicator Simulation method within the barrier. Porosity in the model cells with karst is obtained by analyzing Porospect (FMI-based) and NMR (Nuclear Magnetic Resonance) results on core samples. The model that takes into account caverns shows better convergence with historical data.

References

1. Xinbian Lu, Yan Wang, Fei Tian et al., New insights into the carbonate karstic fault system and reservoir formation in the Southern Tahe area of the Tarim Basin, Marine and Petroleum Geology, 2017, V. 86, pp. 587‒605, DOI: http://doi.org/10.1016/j.marpetgeo.2017.06.023

2. Hollis C., Diagenetic controls on reservoir properties of carbonate successions within the Albian-Turonian of the Arabian Plate, Petroleum Geoscience, 2011, V. 17(3),

pp. 223‒241, DOI: http://doi.org/10.1144/1354-079310-032

3. Tarantini V., Albertini C., Tfaili H. et al., Carbonate karstified oil fields geological prediction and dynamic simulation through equivalent relative permeability curves,

SPE-207462-MS, 2021, DOI: http://doi.org/10.2118/207462-MS

4. Liu Yang, Zhong Li, Mei Zhang et al., Karst architecture characterization of deep carbonate reservoir using image logs in Tarim Basin, West China, Geological Journal, 2023, V. 58(2), DOI: http://doi.org/10.1002/gj.4821

The article deals with the most frequent and significant type of complications in oil and gas well construction which is incompatible drilling zones, such zones should be isolated by casing sections. The main causes of the drilling incompatibility are wellbore instability and the absorption of drilling and grouting fluids. Typically, the fields are confined to sedimentary and carbonate rock formations, such as limestone, dolomite, siltstone, and sandstone. Such complications are often due to the geological properties of the deposits. However, currently, this type of problem occurs in mature deposits where the reservoir pressure becomes lower than the hydrostatic pressure during operation. Preventing and eliminating bottom-type issues significantly increases the efficiency of well construction. The possible solution to reduce the number of intermediate columns in multi-dimensional wells is the development and improvement of technology for fixing pipes with the same diameter. This technology involves the use of expandable casing pipe sections, which maintain a constant internal diameter of the well from the top to the bottom, reducing material costs and simplifying construction logistics. The technology includes the development of casing strings made from ductile steel, as well as the use of special tools and lubricants to ensure the smooth installation of the pipes.

References

1. Kupresan D., Experimental investigation of improved cement isolation by expandable technology, Proceedings of Expandable Tubular Forum, 4–5 November 2011, Houston, Texas.

2. Abusal Yu., Yakhin A.R., Yusupova L.F., Ali N.M., Study of lubricant additives for expansion pipe expansion in monodiameter wells (In Russ.), Neftegazovoe delo, 2024, V. 22, no. 1, pp. 25–33, DOI: https://doi.org/10.17122/ngdelo-2024-1-25-33

3. Kupresan D., Development of a new physical model for experimental assessment of expandable casing technology effect on wellbore cement integrity, Proceedings of 32nd International Conference on Ocean, Offshore and Arctic Engineering, 9–14 June, 2013, Nantes, France, DOI: http://doi.org/10.1115/OMAE2013-10846

4. Kupresan D., Heathman J., Radonjic M., Experimental assessment of casing expansion as a solution for microannular gas migration, Proceedings of 17th Annual Gulf of Mexico Deepwater Technical Symposium, 21–22 August, 2013, New Orleans, Louisiana, DOI: http://doi.org/10.2118/168056-MS

5. Kupresan D., In-situ mechanical manipulation of wellbore cements as a solution to leaky wells, Proceedings of AGU Fall Meeting, 9–13 December 2013, San Francisco, California.

6. Kupresan D., Application of a new physical model of expandable casing technology in mitigation of wellbore leaks, Journal of Canadian Energy Technology & Innovation (CETI), 2013, V. 1, no. 5.

7. Marshev V.I., Akhmetova E.V., Karimova L.I., Saitov I.Kh., Geological and technical features of well construction using expandable shanks technology (In Russ.), Stolypinskiy vestnik, 2022, no. 3, URL: https://stolypin-vestnik.ru/wp-content/uploads/2022/08/58.pdf

8. Radonjic M., Heathman J., Kupresan D., Analysis of defect-free wellbore cement microstructure created by in-situ mechanical manipulation, Proceedings of 21st Annual International Conference on Composites/Nano Engineering, 21–27 July, 2013, Tenerife, Spain.

9. Kupresan D., Experimental assessment of casing expansion as a solution to microannular gas migration, Proceedings of IADC/SPE Drilling Conference, 4–6 March, 2014, Fort Worth, Texas, DOI: http://doi.org/10.2118/168056-MS

10. Radonjic M., Remediation of gas leakage by mechanical manipulation of wellbore cement, Proceedings of 48th US Rock Mechanics / Geomechanics Symposium,

1–4 June, 2014. – Minneapolis.

11. Oyibo A., The use of expandable casing technology as a new remediation tool for microannular gas migration, Proceedings of 5th International Conference on Porous Media and Its Applications in Science, Engineering and Industry, 22–27 June, 2014. – Cona Hawaii.

12. Mulyukov R.R., Imaev R.M., Nazarov A.A., Principles of fabrication of ultrafine-grained materials (In Russ.), Nauchno-tekhnicheskie vedomosti SPbGPU. Fiziko-matematicheskie nauki, 2013, no. 4–1(182), pp. 190–203.

The article addresses the challenges of drilling horizontal wells in carbonate reservoirs of Eastern Siberia, characterized by fractured-vuggy structures, abnormally low reservoir pressure, and extensive tectonic fault networks. The study focuses on mitigating geological risks through the integration of seismic-geological analysis (SGA) and managed pressure drilling (MPD). The SGA methodology combines retrospective analysis of historical drilling data, pre-drill trajectory optimization for cluster pads, well-specific risk assessment, real-time operational monitoring, and post-drill verification of geological forecasts. The implementation of this integrated approach led to notable improvements in key performance indicators: enhanced drilling efficiency per bottom-hole assembly run, reduced time required to complete horizontal sections, and decreased frequency of drilling fluid losses. MPD technology enabled dynamic adjustments of downhole pressure in high-risk zones identified via seismic attributes such as Ant-Tracking, ensuring safer and more controlled operations. The study also highlights emerging challenges encountered in paleo-incision zones of the Vanavar Formation, including uncertainties in boundary delineation and instability in clay-rich intervals. To address these issues, the authors propose refining geological criteria for risk identification and optimizing horizontal section lengths. The research underscores that the synergy between SGA and MPD not only enhances operational reliability but also provides a robust framework for sustainable development of complex reservoirs under challenging geological conditions.

References

1. Pivovar A.V., Kolesov V.A., Kalistratov S.A. et al., Influence of geological conditions on wear-out of the bits in the Riphean deposits of the Yurubcheno-Tokhomskoye field (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2022, no. 1, pp. 50-53, DOI: https://doi.org/10.24887/0028-2448-2022-1-50-53

2. Kryuchkov D.O., Pivovar A.V., Kuznetsova L.S., Kizimov P.L., Real time seismogeological analysis while drilling is the first step to oilfield development efficiency (In Russ.), Neftepromyslovoe delo, 2024, no. 4, pp. 34–42.

3. Pivovar A.V., Filatova V.P., Dmitriev E.M., Rol' seysmogeologicheskogo analiza pri planirovanii i soprovozhdenii bureniya gorizontal'nykh skvazhin (The role of seismogeological analysis in planning and monitoring horizontal well drilling), Proceedings of VI scientific and practical conference “Gorizontal'nye skvazhiny 2024” (Horizontal wells 2024), Moscow, Geomodel' Razvitie Publ., 2024, pp. 198-203.

4. Cherepanov E.N., Soshnikov S.S., Vyrabotka kriteriev dlya zalozheniya skvazhin ekspluatatsionnogo fonda rifeyskogo karbonatnogo kollektora Yurubcheno-Tokhomskogo mestorozhdeniya po dannym 3D seysmorazvedki (Elaboration of criteria for laying wells of the operating stock of the Riphean carbonate reservoir in the central part of the Kamovsky arch of the Baikit anteclise based on 3D seismic data), Proceedings of IV scientific and practical conference “Gorizontal'nye skvazhiny 2021. Problemy i perspektivy” (Horizontal wells 2021. Problems and Prospects), Moscow, 2021, DOI: https://doi.org/10.3997/2214-4609.202154030

The article deals with the problem of early water encroachment of producing wells caused by the tightening of the cone of bottom water. This issue is particularly significant in carbonate reservoirs, where the high heterogeneity of the formation complicates the isolation of water-saturated intervals. The study proposes the use of thermotropic gelling agents (TGA) for large-volume water shut-off jobs (LVWSO). The article presents the results of the implemented pilot work program at one of the carbonate oil fields of the Timan-Pechora province. The criteria for selecting candidate wells, the characteristics of the TGA used, and the technology for conducting workover operations are explored in the article. Emphasis is placed on the importance of choosing the optimal TGA composition based on laboratory studies and pilot testing. Furthermore, a methodology for evaluating the technological effectiveness of water shut-off jobs (WSO) is introduced. The study compares WSO with LVWSO, demonstrating that the application of TGA leads to a significant increase in oil production while reducing water content. The results of the study can be used to enhance the efficiency of oil field development, particularly those affected by early water encroachment. By optimizing LVWSO design and utilizing TGA, there is a potential to increase both the economic and technological efficiency of oil fields development.

References

1. Lanchakov G.A., Ivakin R.A., Griguletskiy V.G., About materials for repair and insulation works of gas and oil wells (In Russ.), Vesti gazovoy nauki, 2011, no. 2(7),

pp. 52–68.

2. Petrakov A.M., Fomkin A.V., Stepanov A.N. et al., Large-volume injection of gelant compositions to isolate bottom water coning in carbonate formations (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2023, no. 2, pp. 33–37, DOI: http://doi.org/10.24887/0028-2448-2023-2-33-37

3. Stepanov A.N., Fursov G.A., Ponomarenko D.M., High volume repair and insulation treatments as effective water coning prevention method (In Russ.), PRONEFT''. Professional'no o nefti = PRONEFT. Professionally about oil, 2023, no. 8(2), pp. 105–111, DOI: https://doi.org/10.51890/2587-7399-2023-8-2-105-111

4. Kubrak M.G., Application of remedial cementing in Samotlor oilfield (In Russ.), Neftegazovoe delo, 2011, no. 2, pp. 82–94, URL: http://www.ogbus.ru/authors/Kubrak/Kubrak_1.pdf

5. Fursov G.A., Ponomarenko D.M., Opyt provedeniya remontno-izolyatsionnykh rabot na mestorozhdeniyakh Tsentral'no-Khoreyverskogo podnyatiya s primeneniem razlichnykh izoliruyushchikh geleobrazuyushchikh sostavov (Experience in carrying out repair and insulation works at the fields of the Central Khoreyver uplift using various insulating gelling compounds), Collected papers “Povyshenie effektivnosti razrabotki neftyanykh mestorozhdeniy” (Improving the efficiency of oil field development), Moscow: Publ. of National Agency for Support and Development, 2017, pp. 75–87.

6. Makarshin S.V., Rogova T.S., Egorov Yu.A. et al., Assessment of opportunities for the use of gels based on aluminum salts for regulating filtration flows in carbonate reservoirs (In Russ.), Proceedings of VNIIneft, 2016, V. 155, pp. 22–36.

7. Patent RU2820437C1, Composition for isolation of water influx to producing oil wells, Inventors: Kornilov A.V., Rogova T.S., Lobova Yu.V., Antonenko D.A., Sansiev G.V.

8. MT RD-04.0-20 3.00. Metodicheskie ukazaniya po raschetu puskovykh prirostov ot geologo-tekhnicheskikh meropriyatiy ot 19.09.2024 (Guidelines for calculating starting increments from geological and technical measures from 09/19/2024), Moscow: Publ. of Zarubezhneft', 2024, 73 p.

A technique is proposed for the effective thicknesses evaluation of a productive section based on determining the pressure recovery curve in various ways, depending on the type of section and reservoir conditions, as well as in combination with techniques used in the fields of Arctic shelf with gas condensate deposits. The issue was solved using a series of computational experiments based on a sector hydrodynamic model built to predict the flow rate based on the results of the wireline formation tests and well logging data. Well logging has high resolution; therefore, even in highly permeable intervals with high vertical anisotropy of permeability, the pressure pulse propagates vertically to the hydrodynamic boundaries of the interlayer and is not limited only by the height of the inlet port of the radial pressure or packer module of formation tester. When configuring the model, the pressure change history coincided with the similar data on formation tester, taking into account the porosity and permeability properties of the reservoir. Based on the conducted research, the consistency of the developed approach of integrating the results of the hydrodynamic logging with hydrodynamic studies data in the gas saturated intervals of the studied objects of the Arctic offshore is proved.

References

1. Shagiev R.G., Issledovanie skvazhin po KVD (Well testing), Moscow: Nauka Publ., 1998, 304 p.

2. Rybal'chenko V.V., Sitdikov N.R., Khoshtariya V.N. et al., Possibility of quantitative estimates of oil and gas deposits' production characteristics by formation wireline tester (In Russ.), Stroitel'stvo neftyanykh i gazovykh skvazhin na sushe i na more, 2016, no. 12, pp. 32-40.

3. Ovechkin A.V., Men'shikov S.N., Chuzhmarev S.S. et al., Increasing the efficiency of Arctic shelf fields preparation for commercial development (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2024, no. 5, pp. 91-97, DOI: http://doi.org/10.24887/0028-2448-2024-5-91-97

4. Flaum C., Galford J. E., Hastings A., Enhanced vertical resolution processing of dual detector gamma-gamma density logs, Houston: Schlumberger Well Service, 1989, 11 p.

5. Ovechkin A.V., Khoshtariya V.N., Fominykh O.V., Results of using hydrodynamic modeling to predict well productivity in Arctic shelf fields (In Russ.), Bulatovskie chteniya, 2024, V. 1, pp. 205-207.

There is often a need to combine reservoirs into a single development object during field development, especially in marine conditions with a limited well stock. This imposes additional requirements for well and reservoir surveillance and management using a set of methods, including production logging, hydrodynamic surveys, tracers, geochemical analysis and others. In case of a hydrodynamic connection between reservoirs, through geological bodies and boundaries, and in condition when a pressure drop occurs during development, interlayer crossflows may happen. This can complicate production allocation and remaining reserves localization, history matching of reservoir models and field development management. Identification and monitoring of inter-layer crossflows occurring in the interwell space are associated with certain difficulties in recording them using direct measurement methods, especially if the crossflow occurs within one phase (gas, oil or water). As a rule, indirect signs establish the fact of cross-flows such as atypical behavior of production wells, calculations of the material balance, history matching of dynamic reservoir models. This paper considers the method of identification and monitoring of inter-layer cross-flows using oil geochemical analysis, supplemented by other field surveillance and analytical data, by the example of the Piltun-Astokhskoye oil and gas condensate field. Geochemical analysis enables to determine the presence of oil from another layer in the production and quantifying its share in the well production.

References

1. Nooruddin H.A., Rahman N.M., А new analytical procedure to estimate interlayer cross-flow rates in layered-reservoir systems using pressure-transient data,

SPE-183689-MS, 2017, DOI: https://doi.org/10.2118/183689-MS

2. Marchenko A.V., Moiseenkov A.V., Parfenov A.M., Khabarov A.V., Specifics of the research program for offshore fields: The case of the Piltun-Astokh oil and gas condensate field of the Sakhalin II project (In Russ.), Aktual'nye problemy nefti i gaza, 2023, no. 2, pp. 216-226, DOI: http://doi.org/10.29222/ipng.2078-5712.2023-41.art15

3. Dashkov R.Yu., Gafarov T.N., Singurov A.A. et al., Features of control over field development from offshore platforms (In Russ.), Gazovaya promyshlennost', 2022,

no. 7(835), pp. 28-38.

4. Pavlov D.V., Vasil'ev A.S., Oil fingerprinting technology for well and reservoir management (In Russ.), SPE-187781-MS, 2017, DOI: https://doi.org/10.2118/187781-MS

5. Pavlov D.V., Gafarov T.N., Oblekov R.G., et al., Geochemical characteristics of oils from Piltun-Astokhskoye oil and gas condensate field (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2025, No. 3, pp. 80-85, DOI: https://doi.org/10.24887/0028-2448-2025-3-80-85

6. Pavlov D.V., Gafarov T.N., Oblekov R.G., et al., Methodology for quantitative oil production allocation using oil geochemical analysis by the example of Piltun-Astokhskoye field (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2025, No. 4, pp. 82-88, DOI: https://doi.org/10.24887/0028-2448-2025-4-82-88

7. Pesotskiy S.A., Marchenko A.V., Gafarov T.N. et al., Value of information estimation methodology for non-developed offshore reservoirs appraisal (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2024, no. 6, pp. 50–54, DOI: https://doi.org/10.24887/0028-2448-2024-6-50-54

8. Gafarov T.N., Oblekov R.G., Khabarov A.V. et al., Clarification of 3D geological and flow model considering the 4D seismic data (In Russ.), Territoriya Neftegaz, 2023,

no. 5–6, pp. 14-18.

9. Pavlov D., Fedorov N., Timofeeva O., Vasiliev A., Improved integrated approach in reservoir modeling by the example of the Astokh field, SPE-196719-MS, 2019,

DOI: https://doi.org/10.2118/196719-MS

This article explores the application of the acoustic technology to assess the integrity of the well casing. The pressing needs of businesses and government agencies are to enhance and refine existing methods for evaluating the condition of structures and their digital simulations. One of the challenges in assessing the integrity of well connections is the absence of a method that enables real-time monitoring during operation, with minimal energy and financial resources for subsurface users. Current research requires interruptions in work and the deployment of specialized equipment, and it is limited to measuring a small portion of the well. Considering the limitations of current technologies, a novel approach is being created that can enhance existing solutions and improve the efficiency of production processes. This approach will also enable the incorporation of new ultrasonic systems for monitoring the structural integrity of extended objects made of ring-shaped cement stone into the standard well construction model. The article outlines the findings of applying the method of pulsed acoustic wave transmission to extended objects up to 8 meters in length, with the aim of detecting longitudinal channels and transverse fractures. The data obtained were compared with the results of simulations conducted using the specialized COMSOL Multiphysics software and tests performed using the AKC-48 geophysical cement meter. The samples were tested with and without insulating material, allowing for a comprehensive assessment of the method's ability to detect cracks and gaps at the interface between the casing and the cement stone.

References

1. Brigante M., Sumbatyan M.A., Acoustic methods for the nondestructive testing of concrete: A review of foreign publications in the experimental field (In Russ.), Defektoskopiya = Russian Journal of Nondestructive Testing, 2013, no. 2, pp. 52–67.

2. Myshkin Yu.V., Metody i sredstva povysheniya effektivnosti akusticheskogo kontrolya trub (Methods and means of increasing the efficiency of acoustic inspection of pipes): thesis of candidate of technical science, St. Petersburg, 2020.

3. Trunov E.I., Ozdoeva A.Kh., Blotskaya A.I. et al., New approaches to the application of the acoustic method for continuous monitoring of well cementing integrity

(In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2024, no. 2, pp. 38–42, DOI: https://doi.org/10.24887/0028-2448-2024-2-38-42

4. Ryden N., Park C.B., Ulriksen P., Miller R.D., Lamb wave analysis for non‐destructive testing of concrete plate structures, Proceedings of Symposium on the Application of Geophysics to Engineering and Environmental Problems 2003, 2003, pp. 782–793, DOI: https://doi.org/10.4133/1.2923224

5. Blotskaya A.I., Karavaev M.A., Kulkova A.S. et al., Laboratory studies to determine if method of pulsed acoustic wave transmission can be used to detect complete cement-to-casing contact, and comparison with simulation results (In Russ.), Territoriya “NEFTEGAZ” = Oil and Gas Territory, 2024, no. 9–10, pp. 44–49.

6. Ermolov I.N., Lange Yu.V., Nerazrushayushchiy kontrol’: Spravochnik (Non-destructive testing), Part 3, Moscow: Mashinostroenie Publ., 2004, 864 p.

The aim to improve the efficiency of oil field development requires the creation of detailed mathematical models capable of describing all the processes taking place in a single production system, both underground and on the surface, and therefore the introduction of advanced tools aimed at obtaining comprehensive and accurate characteristics of the rock actually present in each well. For example, the development of tools for predicting the processes that occur in the reservoir when applying physical-chemical enhance oil recovery methods requires a detailed and highly accurate assessment of the reservoir properties of the rock. This requires the introduction of high-tech methods of geophysical borehole surveying, which can be used to obtain a comprehensive characterization of the production object. The article describes an integrated approach to the development and application of modern AINK-PL and mathematical modeling of processes in the design and implementation of physical-chemical enhance oil recovery methods. AINK-PL enables to obtain more detailed and reliable assessment of reservoir properties of rocks in comparison with standard methods, which is especially important in mathematical modeling of various technologies of physical-chemical enhance oil recovery methods for prediction of their efficiency and optimization of parameters. The joint application of advanced geophysical research technologies and mathematical modeling enables to achieve a synergetic effect and increase the efficiency of oil field development.

References

1. Guidelines for PJSC Rosneft Oil Company No. P1-01.03 M-0089 version 1.00 “Kriterii primenimosti metodov uvelicheniya nefteotdachi dlya obosnovaniya opytno-promyshlennykh rabot na mestorozhdeniyakh Kompanii” (Criteria for applicability of enhanced oil recovery methods to justify pilot work at the Company’s fields), Moscow: Rosneft, 2019, 43 p.

2. Gimaletdinov R.A., Sidorenko V.V., Fakhretdinov R.N. et al., Criteria for effective application of conformance control technologies under the production climate of Gazprom Neft JSC (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2015, no. 5, pp. 78-83.

3. Mukhametzyanov R.N., Gimaletdinov R.A., Yudakov A.N. et al., Development and application of physical and chemical EOR Noyabrsk region (In Russ.), Sovremennye problemy nauki i obrazovaniya, 2015, no. 1–1, 144 p.

4. Gringarten A.C., Interpretation of well test transient data. In: Developments in Petroleum Engineering – 1, edited by Dawe R.A., Wilson D.C., London and New York City: Elsevier Applied Science Publishers, 1985.

5. Trofimov A.S., Berdnikov S.V., Krivova N.R. et al., Generalization of indicator (tracer) studies in the fields of Western Siberia (In Russ.), Territoriya NEFTEGAZ, 2006, no. 12, pp. 72–77.

6. Basyrov M.A., Khabarov A.V., Khanafin I.A. et al., Advanced technologies of well logging and data analysis (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019,

no. 11, pp. 13–17, DOI: https://doi.org/10.24887/0028-2448-2019-11-13-17

7. Khanafin I.A., Nugumanov R.R., Gadel’shin E.V. et al., Towards Russian logging technologies (In Russ.), Karotazhnik, 2019, no. 6(300), pp. 6–13.

8. Makhmutov I.R., Rakaev I.M., Mitrofanov D.A. et al., Application of innovative instrumentation & methodic equipment complex AINK-PL for petrophysical modeling in Rosneft Oil Company (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2023, no. 2, pp. 66–71, DOI: https://doi.org/10.24887/0028-2448-2023-2-66-71

9. Fedorov K.M., Shevelev A.P., Gil’manov A.Ya. et al., New interpretation technique for tracer well tests (In Russ.), Izvestiya vysshikh uchebnykh zavedeniy. Geologiya i razvedka = Proceedings of Higher Educational Establishments: Geology and Exploration, 2023, no. 6, pp. 41–52, DOI: https://doi.org/10.32454/0016-7762-2023-65-6-41-52

10. Rakaev I.M., Gadel’shin E.V., Khanafin I.A. et al., Developing market of domestic hi-tech well survey appliances (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2022, no. 12, pp. 78-82, DOI: https://doi.org/10.24887/0028-2448-2022-12-78-82

11. Fedorov K.M., Gilmanov A.Y., Shevelev A.P. et al., Theoretical analysis of profile conformance improvement due to suspension injection, Mathematics, 2021, no. 9(15), DOI: https://doi.org/10.3390/math9151727

12. Vydysh I.V., Fedorov K.M., Anur’ev D.A., Comparison of the suspension stabilized by polymer treatment efficiency for injection wells of various completions (In Russ.), Vestnik Tyumenskogo gosudarstvennogo universiteta. Fiziko-matematicheskoe modelirovanie. Neft’, gaz, energetika, 2022, V. 8, no. 1(29), pp. 58–74,

DOI: https://doi.org/10.21684/2411-7978-2022-8-1-58-74

13. Fedorov K.M., Vydysh I.V., Morozovskiy N.A. et al., A general approach to modeling technologies of conformance control from injection side (In Russ.), PROneft’. Professional’no o nefti, 2022, no. 7(3), pp. 84–95.

14. Fedorov K., Shevelev A., Gilmanov A. et al., Injection of gelling systems to a layered reservoir for conformance improvement, Gels, 2022, no. 8,

DOI: https://doi.org/10.3390/gels8100621

15. Fedorov K.M., Shevelev A.P., Vydysh I.V. et al., Methodology for assessing and predicting the reaction of producers to the conformance control of injectors (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2022, no.9, pp. 106–110, DOI: https://doi.org/10.24887/0028-2448-2022-9-106-110

16. Fedorov K.M., Gil’manov A.Ya., Shevelev A.P., New approach to simulation and efficiency prediction of precipitation and gel enhanced oil recovery methods (In Russ.), Izvestiya TPU. Inzhiniring georesursov = Bulletin of the Tomsk Polytechnic University. Geo Assets Engineering, 2023, V. 334, no. 5, pp. 85–93.

17. Fedorov K.M., Ganopolskiy R.M., Gilmanov A.Y., Shevelev A.P., Optimization procedure for conformance control, Theoretical Foundations of Chemical Engineering, 2024, V. 58, no. 3, pp. 555–563, DOI: https://doi.org/10.1134/S0040579524601092

18. Barmakov Yu.N., Zverev V.I., Mikerov V.I. et al., Osnovy yaderno-fizicheskikh metodov issledovaniya skvazhin (Fundamentals of nuclear-physical methods of well research), Moscow: Buki Vedi Publ., 2021, 250 p.

19. Khomyakov A.S., Sovremennoe sostoyanie apparatury impul’snogo neytronnogo karotazha vo FGUP VNIIA (Current state of pulsed neutron logging equipment at FSUE VNIIA), Proceedings of Proceedings of the II International Scientific and Practical Conference “Geologiya i geofizika – 2022: nauka, proizvodstvo, innovatsii” (Geology and Geophysics – 2022: Science, Production, Innovation), Ufa, 13–14 October 2022, Tver: PoliPRESS Publ., 2022, pp. 321–324.

20. Zverev V.I., Khomyakov A.S., Presnyakov A.Yu. et al., Pulse neutron logging tools made by FGUP VNIIA (In Russ.), Karotazhnik, 2024, no. 2(328), pp. 35–42.

21. Bikmetova A.R., Vakhitova G.R., Sharafutdinov R.F. et al., Opredelenie mineralogicheskogo sostava gornykh porod po rezul’tatam INGK-S (Determination of the mineralogical composition of rocks based on the results of INGK-S), Collected papers “Geologo-geofizicheskie issledovaniya neftegazovykh plastov” (Geological and geophysical studies of oil and gas reservoirs), Proceedings of V All-Russian Youth Scientific and Practical Conference, Ufa, 17 September 2020, Ufa: Publ. Bashkir State University, 2020, pp. 99–102.

22. Privalova O.R., Bayburina E.F., Belokhin V.S., Zyryanova I.A., Petrophysical tuning of pulsed neutron logging to improve the efficiency of reservoir oil saturation forecasting (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2023, no. 12, pp. 94–99, DOI: https://doi.org/10.24887/0028-2448-2023-12-94-99

23. Basyrov M.A., Mitrofanov D.A., Makhmutov I.R. et al., The development of the technique for measuring mass fractions of chemical elements using AINK-PL logs

(In Russ.), Karotazhnik, 2021, no. 8(314), pp. 121–130.

24. Mikerov V.I., Khomyakov A.S., Mitrofanov D.A. et al., Pulse neutron log spectra processing (based on foreign publications) (In Russ.), Karotazhnik, 2024, no. 2(328), pp. 123–142.

25. Kopylov S.I., Sokolov S.V., Khomyakov A.S. et al., Software and methods for AINK-PL (pulse-neutron gamma-spectrometry tool) (In Russ.), Karotazhnik, 2024,

no. 2(328), pp. 43–65.

26. Rodivilov D.B., Mukhamet’yanov A.S., Makhmutov I.R. et al., First lessons learned when applying the AINK-PL hardware complex to assess gas saturation in complex geological environment of Achimov reservoirs (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2024, no. 11, pp. 26-31, DOI: https://doi.org/10.24887/0028-2448-2024-11-26-31

27. Stromberg A.G., Fizicheskaya khimiya (Physical chemistry), Moscow: Vysshaya shkola Publ., 1999, 527 p.

28. Zemtsov Yu.V., Mazaev V.V., Sovremennoe sostoyanie fiziko-khimicheskikh metodov uvelicheniya nefteotdachi (literaturno-patentnyy obzor) (Current state of physicochemical methods for enhancing oil recovery (literature and patent review)), Ekaterinburg: Izdatel’skie resheniya Publ., 2021, 239 p.

The article considers the possibility of building an offshore wind power plant using the example of the energy supply of the Y. Korchagin field in the northern section of the Caspian Sea. Wind is a renewable (alternative) energy source. Its main advantage is that the wind blows everywhere and constantly, and the construction of power plants is not limited to the earth. Based on the analysis of soils in the proposed construction area, the foundation structure of the wind turbine in the form of a «tripod» was selected. The equipment for transportation and installation of the foundation and technological equipment of the wind turbine was selected. Highly efficient concrete mix compositions are proposed for the final fixation of the wind turbine foundation and significant protection from ice loading. The types of wind turbines were selected, in addition to the existing energy equipment at the field, to meet the electricity needs for the operation of buildings and equipment at the Y. Korchagin field. Calculations of the wave and wind loads acting on the structure of the base of the wind turbine, typical for this construction area, have been performed. It is established that the stability of the upper part of the wind turbine structure from the effects of wave and wind loads is ensured.

References

1. Mudretsov A.F., Tulupov A.S., Issues of alternative energy development in Russia (In Russ.), Vestnik Tomskogo gos. universiteta. Ekonomika, 2016, no. 4, pp. 38–45, DOI: https://doi.org/10.17223/19988648/36/3

2. Berdigulov A.N., Problemy osvoeniya shel'fa Severnykh morey (Problems of development of the shelf of the north seas), Collected papers “Informatsionnye tekhnologii kak osnova progressivnykh nauchnykh issledovaniy” (Information technology as a basis for progressive scientific research), Proceedings of International scientific and practical conference, Izhevsk, 14 April 2020, Izhevsk: Udmurtskiy universitet Publ., 2020, pp. 112-119.

3. Zolotukhin A.B., Gudmestad O.T., Ermakov A.I. et al., Osnovy razrabotki shel'fovykh neftegazovykh mestorozhdeniy i stroitel'stvo morskikh sooruzheniy v Arktike (Fundamentals of the development of offshore oil and gas fields and the construction of offshore structures in the Arctic), Moscow: Neft' i gaz Publ., 2000, 770 p.

4. Kerimov I.A., Debiev M.V., Magomadov R.A-M., Khamsurkaev Kh.I., Solar and wind energy resources of the Chechen Republic (In Russ.), Inzhenernyy vestnik Dona, 2012, no. 1, URL: ivdon.ru/ru/magazine/archive/n1y2012/677

5. Abdimalik M.E., Vetrogenerator (Wind generator), Proceedings of XLII International scientific and practical conference within the framework of the implementation of the Message of the President of the Republic of Kazakhstan N. Nazarbayev “Novye vozmozhnosti razvitiya v usloviyakh chetvertoy promyshlennoy revolyutsii” (New development opportunities in the context of the fourth industrial revolution), edited by Ibraev B.M., 2018, pp. 229–231.

6. Zavyazkina A.A., Sirnova E.M., Analiz proektov stroitel'stva i obsluzhivaniya offshornykh VES v mirovykh EES (Analysis of offshore wind farm construction and maintenance projects in the world's power grids), Proceedings of The fifteenth all-Russian (seventh international) scientific and technical conference of students, postgraduates and young scientists, Part. 3, 2020, 90 p.

7. Kulikov N.N., Offshornye tekhnologii vetroenergetiki v prikaspiyskom regione (Offshore wind energy technologies in the Caspian region), Collected papers “Innovatsionnye tekhnologii sovremennoy nauchnoy deyatel'nosti: strategiya, zadachi, vnedreniya” (Innovative technologies of modern scientific activity: strategy, tasks, implementation), Kazan': Aeterna Publ., 2019, pp. 24–26.

8. Rudenko V.V., Blagovidova I.L., P'yanov A.V., D'yachuk N.S., Experience in designing and conducting operations during construction of offshore facilities (In Russ.), Morskoy vestnik, 2020, no. S1, pp. 41–45.

9. Filatova A.S., Offshore wind energy (In Russ.), Izvestiya Tul'skogo gosudarstvennogo universiteta. Tekhnicheskie nauki, 2018, no. 12, pp. 63-66.

10. Green R., Vasilakos N., The economics of offshore wind, Energy Policy, 2011, V. 39, pp. 496–502, URL: https://repec.cal.bham.ac.uk/pdf/10-20.pdf

11. Serebryakova O.A., Engineering and mineralogical composition of the Caspian Sea soils (In Russ.), Geologiya. Izvestiya otdeleniya nauk o zemle i prirodnykh resursov, 2009, no. 14, C. 74–77.

12. Panasyuk L.N., Akopyan V.F., Akopyan A.F., Chantkha Kh., New types of piles (In Russ.), Inzhenernyy vestnik Dona, 2011, no. 2(16), pp. 215-219, URL: ivdon.ru/ru/magazine/archive/n2y2011/437

13. Pankov V.I., Classification of ships and floating technical facilities of oil and gas production fleet (In Russ.), Sudostroenie, 1999, no. 6(727), pp. 17-20.

14. Nikitina A., High production standards: Liebherr offshore cranes (In Russ.), Delovoy zhurnal Neftegaz.ru, 2019, pp. 34–37.

15. Perfilov V.A., Khuadonov A.A., Vysokoprochnyy beton dlya stroitel'stva neftegazovykh sooruzheniy na more (High-strength concrete for offshore oil and gas construction), Collected papers “Aktual'nye problemy i perspektivy razvitiya stroitel'nogo kompleksa” (Current problems and development prospects of the construction complex), Proceedings of International scientific and practical conference, 1–2 December 2020, Volgograd: Publ. of Volgograd State Technical University, 2020, Part 1, pp. 166–170.

16. Perfilov V.A., Gabova V.V., Nanomodified constructional fiber-reinforced concrete, Proceedings of MATEC Web of Conferences, 2017, V. 129, DOI: http://doi.org/10.1051/matecconf/201712905021

17. SP 20.13330.2016. Nagruzki i vozdeystviya (Loads and impacts), Moscow: Publ. of Ministry of Construction and Housing and Communal Services of the Russian Federation, 2016.

18. SP 38.13330.2018. Nagruzki i vozdeystviya na gidrotekhnicheskie sooruzheniya (volnovye, ledovye ot sudov) (Loads and impacts on hydraulic structures (waves, ice from ships)), Moscow: Publ. of Ministry of Construction and Housing and Communal Services of the Russian Federation, 2018.

The article is dedicated to the issue of creating predictive models based on trained user-defined and automated neural networks for forecasting certain production characteristics of horizontal wells with multistage hydraulic fracturing. According to the authors, the predicted characteristics are fundamental in assessing the potential of oil wells or the effectiveness of well intervention techniques. A numerical prediction (regression) task was defined and solved, a comprehensive approach to training both user-defined and automated neural networks is presented, the architecture and free parameters of neural networks are experimentally determined, and an optimal set of input data for modeling is identified using the «backwards elimination» method, which is often applied in statistics but rarely used with neural networks. It is noted that the process of training neural network is largely hidden and remains unexplained (which is why neural networks have a reputation as a «black box»). In turn, the conducted research demonstrates criteria for selecting the most accurate predictive models, assessing the importance of variables for analysis, and tools for evaluating model outputs, which significantly unveils the «black box» of the neural network process. Based on the geological nature of the studied object, the possibility of replicating trained predictive models is demonstrated, without being limited to a single subsurface area. Thus, the authors propose implementing neural network predictive models capable of correctly forecasting well production characteristics under conditions of significant data variability and heterogeneity typical of many operations in field development.

References

1. Nisbet R., Elder J., Miner G., Handbook of statistical analysis and data mining applications, Academic Press, 2009, 822 p., DOI: https://doi.org/10.1016/B978-0-12-374765-5.X0001-0

2. Neyronnye seti. STATISTICA Neural Networks: Metodologiya i tekhnologii sovremennogo analiza dannykh (Neural networks. STATISTICA Neural Networks: Methodology and technologies of modern data analysis): edited by Borovikov V.P., Moscow: Goryachaya liniya – Telekom Publ., 2008, 392 p.

3. Markin V.A., Markina L.V., Bayramov V.R., Lobanok M.Yu., Data Mining methods as a decision support system under conditions of data limitation (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2024, no. 5, pp. 138–142, DOI: https://doi.org/10.24887/0028-2448-2024-5-138-142

To develop a digital model of a gathering and transportation system for field production that enables effective operational management and optimization, it is necessary to adapt the results of hydraulic calculations performed using this model to actual field data. This article presents methods for adapting hydraulic calculations for pipelines transporting single-phase (including non-Newtonian) fluids and gas-liquid mixtures. The adaptation process involves adjusting parameters such as the equivalent diameter, which is reduced relative to the nominal diameter due to deposits of various origins, and the equivalent roughness of the internal pipe surface. The proposed methods enable the fine-tuning of operational parameters for each network segment, account for the hydrodynamic characteristics of different fluid types, exhibit low sensitivity to operational regime variations, require minimal field data for calibration, and help identify cases where a reassessment and refinement of input data is preferable to adaptation. Methodologies and algorithms for adapting the hydraulic regimes of pipeline networks of any complexity, including those containing closed loops, were developed and implemented in the Pipe FM software, enabling users to select the most appropriate adaptation method. A comparative analysis based on specific case studies demonstrated that the most effective approach is the equivalent diameter selection method. This approach enhances the efficiency of gathering and transportation system management and optimization by significantly improving adaptation accuracy compared to international counterparts.

References

1. Elin N.N., Stadnichenko O.A., Zvyagin M.A., Kvitachenko I.O., Critical analysis of hydraulic methods for gas condensate flows in wells and oilfield pipelines (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2023, no. 8, pp. 76–81, DOI: https://doi.org/10.24887/0028-2448-2023-8-76-81

2. URL: https://oissolutions.net/wp-content/uploads/2020/03/OIS_Pipe_onepager_A3_eng_fin.pdf

3. Certificate of state registration of the computer program no. 2021610166 RF. Informatsionno-analiticheskaya sistema ekspluatatsii truboprovodov OIS PIPE+ (Information and analytical system for pipeline operation OIS PIPE+).

4. Inzhenernoe programmnoe obespechenie Petroleum Experts (Petroleum Experts Engineering Software),

URL: http://itps.com/uploads/files/Petex%20IPM%20Brochure%20RUS.pdf

5. URL: https://sis.slb.ru/products/

6. R Gazprom 2-3.5-1037-2016. Modelirovanie tekhnologicheskikh rezhimov ekspluatatsii sistem sbora i vnutripromyslovogo transporta gaza senomanskikh zalezhey (Modeling of technological modes of operation of collection systems and in-field transportation of gas from Cenomanian deposits), St. Petersburg: Publ. of Gazprom, 2016, 20 p.

7. Brill J.P., Mukherjee H., Multiphase flow in wells, SPE Monograph, Henry L. Dogherty Series, V.17, 1999, 164 p.

8. Elin N.N., Nassonov Yu.V., Ashkarin N.I. et al., Razrabotka i ekspluatatsiya matematicheskikh modeley sistem obustroystva neftyanykh mestorozhdeniy (Development and exploitation of mathematical models of oil fields development systems), Ivanovo, Publ. of IGKhTU, 2006, 272 p.

9. Idelchik I.E., Spravochnik po gidravlicheskim soprotivleniyam (Handbook of hydraulic resistance): edited by Shteynberg M.O., Moscow: Mashinostroenie Publ., 1992, 672 p.

10. Wilkinson W.L., Non-Newtonian fluids. Fluid mechanics, mixing and heat transfer, Pergamon Press, London, 1960.

11. Lur’e M.V., Matematicheskoe modelirovanie protsessov truboprovodnogo transporta nefti, nefteproduktov i gaza (Mathematical modeling of oil and gas pipeline transport), Moscow: Publ. of Gubkin Russian State University of Oil and Gas, 2012, 456 p.

12. Gritsenko A.I., Klapchuk O.V., Kharchenko Yu.A., Gidrodinamika gazozhidkostnykh smesey v skvazhinakh i truboprovodakh (Hydrodynamics of gas-liquid mixtures in wells and pipelines), Moscow: Nedra Publ., 1994, 238 p.

In ferrite-pearlite steel pipelines manufactured using technologies from the mid-1960s, a steady increase in brittle fractures is observed after 15-20 years of operation in northern regions at sub-zero ambient temperatures. A number of publications propose to consider the influence of daily temperature changes on the bearing capacity of pipelines by algebraically adding the reduced number of thermal cycles to the total number of loading cycles resulting from operating pressure pulsations and thus determining the total number of loading cycles. This approach does not take into account the impact of sub-zero temperatures on the physical and mechanical properties of the structural metal during long-term operation. The article presents the analysis of the fracture of pipelines made of ferrite-pearlite steels structurally reinforced by increasing the volume fraction of pearlite during operation in areas with sub-zero mean annual temperatures and large-gradient daily changes in sub-zero temperatures. The combined effect of long-term cyclic loading, internal shrinkage strains of structural elements with different crystal lattices and sharp changes in sub-zero temperatures create the plasticity reduction effect and an increase in the brittle fracturing trend of ferrite-pearlite steels at ambient temperatures above the cold brittleness threshold. A methodology for assessing the influence of sub-zero temperatures on the properties of pipe steels is proposed. For ferrite-pearlite class steels, sub-zero temperatures causing either significant or, in some steels, extraordinary drops in impact strength are determined at levels substantially above the cold brittleness thresholds. These sub-zero temperature ranges are defined as «low temperature brittleness ranges».

References

1. Mazur I.I., Ivantsov O.M., Bezopasnost' truboprovodnykh sistem (Safety of pipeline systems), Moscow: Elima Publ., 2004, 560 p.

2. Zorin E.E., Stepanenko A.I., Change in crack resistance of pipe steels type 09G2S and their welded joints at low temperatures (In Russ.), Stroitel'stvo truboprovodov, 1991, no. 4, pp. 37–39.

3. Zorin E.E., Lanchakov G.A. Stepanenko A.I., Corrosion-mechanical strength and failure statistics of pipelines (In Russ.), Gazovaya promyshlennost', 1991, no. 10, pp. 14–16.

4. Larionov V.P., Zorin E.E., Use of rare and rare earth elements to produce cold-resistant structural steels (In Russ.), Svarochnoe proizvodstvo, 2003, no. 10, pp. 42–44.

5. Goritskiy V.M., Terent'ev V.F., Struktura i ustalostnoe razrushenie metallov (Structure and fatigue failure of metals), Moscow: Metallurgiya Publ., 1980, 244 p.

6. Anuchkin M.P., Nesushchaya sposobnost' svarnykh magistral'nykh truboprovodov vysokogo davleniya. Prochnost' trub magistral'nykh truboprovodov (Load-bearing capacity of welded high-pressure main pipelines. Strength of main pipeline pipes), Moscow: Publ. of USSR Gazprom, 1965, pp. 21–27.

7. Borodavkin P.P., Podzemnye magistral'nye truboprovody (Underground main pipelines), Moscow: Nedra Publ., 1982, 276 p.

8. Zorin E.E., Lanchakov G.A., Pashkov Yu.I., Stepanenko A.I., Rabotosposobnost' truboprovodov (Pipeline performance), Part 2. Soprotivlyaemost' razrusheniyu (Destruction resistance), Moscow: Nedra Publ., 2001, 350 p.

9. Zorin E.E., Stepanenko A.I., Resistance to destruction of process pipelines made of steel type O9G2S during thermal cycling in the climatic temperature range (In Russ.), Gazovaya promyshlennost', 1994, no. 2, pp. 22–23.

10. Larionov V.P., Zorin E.E., Use of niobium to increase the strength of welded joints in low-alloy steels (In Russ.), Zavodskaya laboratoriya, 2003, no. 9, pp. 62–63.

11. Larionov B.P., Zorin E.E., Using rare and rare-earth elements for the production of cold resistant constructional materials, Cambridge, England, 2004, V. 18, no. 4,

pp. 301-304, DOI: https://doi.org/10.1533/wint.2004.3275

12. Neganov D.A., Zorin E.E., Zorin N.E., Assessment of influence of surface crack-like stress concentrators on main pipeline operability (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2021, V. 11, no. 1, pp. 8–15,

DOI: https://doi.org/10.28999/2541-9595-2021-11-1-8-15

13. Radionova S.G., Revel-Muroz P.A., Lisin Yu.V. et al., Scientific-technical, socio-economic and legal aspects of oil and oil products transport reliability (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2016, no. 5 (25), pp. 20–31.

14. Voronov A.G. et al., Information and analytical support for planning the replacement of linear part sections of main oil pipelines (In Russ.), Nauka i tekhnologii truboprovodnogo transporta nefti i nefteproduktov, 2022, V. 12, no. 1, pp. 18–33, DOI: https://doi.org/10.28999/2541-9595-2022-12-1-18-33