The article discusses the theoretical prerequisites for the formation of hydrocarbon fields at great (more than 6 km) depths from the point of view of the possibility of generation processes, their features, boundary conditions for the preservation of accumulations and the direction of fluid transformation under the influence of high temperatures and pressures, as well as changes in the reservoir filtration properties of reservoirs and seals. Until recently, at the axiom level, there was an idea that the distribution of oil accumulations is limited to a depth of 4-5 km, while the possibility of the existence of gas and condensate accumulations at great depths was not in doubt. Such zoning of hydrocarbons accumulations was the basic one in the sedimentary migration theory. However, large-scale drilling of wells to ultra-deep horizons and the discovery of oil accumulations in them forced us to reconsider these views and look for an explanation for this phenomenon. The article focuses on the possibility of the formation of liquid hydrocarbons accumulations based on the analysis of hydrocarbon systems, the relationship and functioning of their individual elements in extreme conditions. The study of the features of the realization of generation potential of specific source rocks with a high (15% or more) initial content of organic matter, which accumulated in relatively deep-water conditions, showed that intensive processes of oil generation in them are directly related to the formation of microcracks at high temperatures and pressures. The article is based on the summarization of a large number of published data on the results of drilling deep wells onshore in China and the Caspian Basin, as well as on the shelf of the Gulf of Mexico and in Norway. Some geological criteria favorable for the formation of oil and gas potential at great depths have been determined.

References

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2. Nadeau P.H., Bjørkum P.A., Walderhaug O., Petroleum system analysis: impact of shale diagenesis on reservoir fluid pressure, hydrocarbon migration and biodegradation risks, In: Petroleum geology: North-West europe and global perspectives: edited by Doré A.G., Vining B., Proceedings of the 6th Petroleum Geology Conference, Geological Society, London, 2005, pp. 1267–1274, http://dx.doi.org/10.1144/0061267

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4. Iskaziev K.O., Zhemchugova V.A., Kosenkova N.N. et al., Geologo-geokhimicheskie predposylki neftegazonosnosti podsolevykh otlozheniy Severnoy bortovoy zony Prikaspiyskoy vpadiny (Geological and geochemical prerequisites for the oil and gas potential of subsalt deposits of the northern marginal zone of the Pre-Caspian depression), URSS Publ., 2019, 205 p.

5. Feyzullayev A.A., Lerche I., Temperature-depth control of petroleum occurrence in the sedimentary section of the South Caspian basin, Petroleum Research, 2020, V. 5, no. 1, pp. 70–76, https://doi.org/10.1016/j.ptlrs.2019.10.003

6. Maksimov S.P., Lodzhevskaya M.I., Samvelov R.G. et al., Geologicheskie usloviya neftegazonosnosti na bol’shikh glubinakh (Geological conditions of oil and gas potential at great depths), In: Generatsiya i migratsiya nefti (Generation and migration of oil), Proceedings of International Geological Congress, XXVIII session, Moscow, 1988, pp. 83–92.

7. Keith S.B., Spieth V., Rasmussen J.C., Zechstein-Kupferschiefer mineralization reconsidered as a product of ultra-deep hydrothermal, mud-brine volcanism, 2017, https://doi.org/10.5772/intechopen.72560.

8. Chai Z., Chen Z., Liu H. et al., Light hydrocarbons and diamondoids of light oils in deep reservoirs of Shuntuoguole Low Uplift, Tarim Basin: Implication for the evaluation on thermal maturity, secondary alteration and source characteristics, Marine and Petroleum Geology, 2020, https://doi.org/10.1016/j.marpetgeo.2020.104388

9. Caineng Zou, Du Jinhu, Xu Chunchun, Formation, distribution, resource potential, and discovery of Sinian–Cambrian giant gas field, Sichuan Basin, SW China, Petroleum Exploration and Development, 2014, V. 41, no. 3, https://doi.org/10.1016/S1876-3804(14)60036-7

10. Ehrenberg S.N., Nadeau P.H., Sandstone vs. carbonate petroleum reservoirs: A global perspective on porosity-depth and porosity-permeability relationships, AAPG Bulletin, 2005, V. 89, no. 4, pp. 435–445,  pp. 306-324, DOI:10.1016/S1876-3804(14)60036-7

11. Godo T., The Smackover-Norphlet petroleum system, deepwater Gulf of Mexico: Oil fields, oil shows, and dry holes, Gulf Coast Association of Geological Societies, 2019, no. 8, pp. 104-152.

12. Xusheng Guo, Dongfeng Hu, Yuping Li, J. Duan, Chunhui Ji, Hua Duan, Discovery and theoretical and technical innovations of Yuanba gas field in Sichuan Basin, SW China, Petroleum Exploration and Development, 2018, V. 45(1), pp. 14–26, https://doi.org/10.1016/S1876-3804(18)30002-8

13. Sarg J.F., Oil and gas reservoirs and coral reefs, In: Encyclopedia of Modern Coral Reefs: edited Hopley D., Encyclopedia of Earth Sciences Series, Springer, Dordrecht, 2011, https://doi.org/10.1007/978-90-481-2639-2_121

14. Ngia N.R., Hu M., Gao D., Hydrocarbon reservoir development in reef and shoal complexes of the Lower Ordovician carbonate successions in the Tazhong Uplift in central Tarim basin, NW China: constraints from microfacies characteristics and sequence stratigraphy, J Petrol Explor Prod Technol., 2020, V. 10, pp. 2693–2720, https://doi.org/10.1007/s13202-020-00936-y

15. Lukas A., Diamond L.W., Mazurek M., Davis D.W., Creation of secondary porosity in dolostones by upwelling basement water in the Foreland of the Alpine Orogen, Geofluids, 2019, Article ID 5210404, 23 p., https://doi.org/10.1155/2019/5210404

16. Qi L., Characteristics and inspiration of ultra-deep fault-karst reservoir in the Shunbei area of the Tarim Basin, China Petroleum Exploration, https://doi.org/10.3969/j.issn.1672–7703.2020.01.010.

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The Iraqi Kurdistan territory is considered a unique region for the the petroleum geology, due to the fact that, on the one hand, part of the reservoirs, for example, of the Cenozoic age, was formed in relatively deep sea conditions, and was present with low-permeability deposits, mainly argillaceous limestones, where the role of fracturing in enhancing the reservoirs cannot be overestimated, and on the other hand, provide a wide opportunities for studying all elements of petroleum systems, including the reservoir. This study is focusing on a group of formations of significant economic interest to the oil industry in Iraq, namely the Lower Fars, Jeribe and Pilla Spi formations of the main Cenozoic (Tertiary) age. The above-mentioned formations are believed to play an important role in natural hydrocarbon systems. Some of them are good reservoirs and other ones are cap rocks. The availability of the very well exposed reservoir rocks on the outcrop provides a possibility to implement a wide range of fracture analysis and use the results to better predict natural fracture characteristics of subsurface fracture network of the Tertiary reservoirs in all Iraqi Kurdistan fields. One of the practical and very useful analysis is to use mathematical computation method within a frame of the MATLAB software. A modern method that did not well credited yet in the oil and gas industry. In this paper we utilize a photogrammetry technique in integration with mathematical computation to extract the full set of fracture characteristics from outcrop. Such Method is just started to get spotlight in the Oil and Gas Industry and expected to gain more attraction by researchers in soon future.

References

1. Awdal A.H., Braathen A., Wennberg O.P., Sherwani G.H., The characteristics of fracture networks in the Shiranish formation of the Bina Bawi anticline; comparison with the Taq Taq field, Zagros, Kurdistan, NE Iraq, Petroleum Geoscience, 2013, V. 19(2), pp. 139-155, http://dx.doi.org/10.1144/petgeo2012-036

2. Reif D., Grasemann B., Faber R.H., Quantitative structural analysis using remote sensing data: Kurdistan, northeast Iraq, AAPG Bulletin, 2011, V. 95 (6), pp. 941–956, https://doi.org/10.1306/11151010112

3. Jassim S.Z., Goff J.C., The geology of Iraq, Dolin, Prague, 2006, 341 p.

4. Fard I.A., Braathen A., Mokhtari M., Alavi S.A., Interaction of the Zagros Fold–Thrust Belt and the Arabian-type, deep-seated folds in the Abadan Plain and the Dezful Embayment, SW Iran, Petroleum Geoscience, 2006, no. 12, pp. 347–362, http://dx.doi.org/10.1144/1354-079305-706

5. Aqrawi A.A.M. et al., The petroleum geology of Iraq, Scientific Press, Beaconsfield, 2010, 424 p.

6. Wennberg O.P., Svana T., Azzizadeh M. et al., Fracture intensity vs. mechanical stratigraphy in platform top carbonates: the Aquitanian of the Asmari Formation, Khaviz Anticline, Zagros, SW Iran, Petroleum Geoscience, 2006, no. 12, pp. 235–245, http://dx.doi.org/10.1144/1354-079305-675

7. Ahmadhadi F., Daniel J.-M., Azzizadeh M., Lacombe O., Evidence for pre-folding vein development in the Oligo-Miocene Asmari Formation in the Central Zagros Fold Belt, Iran, Tectonics, 2008, V. 27, no. 1, https://doi.org/10.1029/2006TC001978

8. Casini G., Gillespie P.A. et al., Sub-seismic fractures in foreland fold and thrust belts: Insight from the Lurestan Province, Zagros Mountains, Iran, Petroleum Geoscience, 2011, V. 17, pp. 263–282, http://dx.doi.org/10.1144/1354-079310-043

9. Lacombe O., Bellahsen N., Mouthereau F., Fracture patterns in the Zagros Simply Folded Belt (Fars, Iran): Constraints on early collisional tectonic history and role of basement faults, Geological Magazine, 2011, V. 148, pp. 940–963, https://doi.org/10.1017/S001675681100029X

10. Tavani S., Storti F., Soleimany B., et al., Geometry, kinematics and fracture pattern of the Bangestan anticline, Zagros, SW Iran, Geological Magazine, 2011, V. 148, pp. 964–979, DOI: https://doi.org/10.1017/S0016756811000197

11. Priest S.D., Discontinuity analysis for rock engineering, Chapman & Hall, London, 1993, 492 p.

12. Terzaghi R.D., Source of error in joint surveys, Geotechnique, 1965, V. 15, pp. 287–304, https://doi.org/10.1680/geot.1965.15.3.287

13. Odling N.E., Gillespie P. et al., Variations in fracture system geometry and their implications for fluid flow in fractured hydrocarbon reservoirs, Petroleum Geoscience, 1999, V. 5, pp. 373–384, http://dx.doi.org/10.1144/petgeo.5.4.373

14. Price N.J., Fault and joint development in Brittle and Semi-brittle rock, Pergamon Press, Oxford, 1966, 176 p.

15. Healy D., Rizzo R.E., Cornwell D.G. et al., FracPaQ: a MATLAB™ toolbox for the quantification of fracture patterns, Journal of Structural Geology, 2017, V. 95, https://doi.org/10.1016/j.jsg.2016.12.003

A mud supported sandstone core sample was selected to investigate the effect of various structural parameters including anisotropic clay platelets shapes and spatial orientation, fractures volume, shape and orientation on seismic waves velocities. For the selected cylindrical core sample, the following physical parameters were measured in laboratory pressure and temperature while keeping the sample dry: total porosity, permeability, bulk density, mineral content, and acoustic waves velocities radially in 7 different azimuths as well as along the vertical axial direction. Thereafter, a primary Rock Physic model is constructed based on the visual inspection of the SEM images. In the primary dual-porosity, constructed model the clay platelets morphology and spatial orientations were considered to be model parameters along the pores (cavities with aspect ratio between 0.1 and 1) and fractures (cavities with aspect ratio between 10-5 and 10-2) morphology and spatial orientations. The conducted sensitivity analysis depicted that the seismic waves velocities are not sensitive to the considered structural parameters for the clay platelets and pores. Therefore, the primary Rock Physic model was modified to delete the uninfluential parameters. Omitting the uninfluential parameters increases the weight of the influential parameters by decreasing the unknowns and degree of freedom for the model. The interior point algorithm was used to solve the inverse problem and find the model parameters. Seismic waves velocities were regenerated using the estimated parameters in the azimuths where the waves velocities measurements were conducted. Comparing the estimated and measured waves velocities shows that the best estimation was obtained for the compressional waves velocities (root mean squared error (RMSE) – 0.5 %), the estimation error is more for fast shear waves (RMSE – 1 %) and the most erroneous results are obtained when slow shear waves are estimated (RMSE – 2.5 %). The reason for more erroneous results obtained for the slow shear waves estimation might be because of the measurement error which is more for the slow shear waves velocity measurements in the laboratory.

References

1. Smith T.M. et al., Rock properties in low-porosity/low-permeability sandstones, The Leading Edge, 2009, no. 28(1), pp. 48–59, https://doi.org/10.1190/1.3064146

2. Huang X.-R. et al., Brittleness index and seismic rock physics model for anisotropic tight-oil sandstone reservoirs, Applied Geophysics, 2015, no. 12(1), pp. 11–22, https://doi.org/10.1007/s11770-014-0478-0

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8. Ghasemi M.F., Bayuk I.O., Bounds for pore space parameters of petroelastic models of carbonate rocks, Izvestiya, Physics of the Solid Earth, 2020, V. 56(2), pp. 207–224, https://doi.org/ 10.1134/S1069351320020032

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The Lower Triassic Montney Formation of the Western Canada Sedimentary Basin is a World-class resource with 450 TCF of gas reserves, 14,520 MMBBL of natural gas liquids reserves and 1,125 MMBBL of oil reserves. Resources are primarily hosted in organic-rich and organic-lean low-permeability siltstones and to a lesser extent, very fine-grained silty sandstones. Distal portions of Montney fans contain well-sorted siltstones and clay-rich shales in various proportions. At a certain part of the paleo-basin, they are also intercalated with organic-rich (anoxic) shales, forming a hybrid “sweet-spot” for the play. Deposition of the distal turbidite sequences took place in an anoxic - dysoxic environment, with several periods of higher oxygen levels. The environment of deposition is related to pore structure and amount of three porosities: nano-pores associated with kerogen, micro-pores of clay minerals, and intergranular micro-pores of siltstones. Organics composed of type I/II oil- prone kerogen are responsible for hydrocarbons and overpressure generation; Siltstones – providing storage space and sufficient matrix permeability (higher than average in typical self-sourced unconventionals); and finally, Clay-bound water acts as a local capillary-pressure seal.

Montney turbidites are 500-900 ft thick, covering area of approximately 130,000 sq km, and even with low porosity (6%) and rather low recovery (<10%), presenting a very attractive target showing enough resilience to “commodity price volatility”.

References

1. Davies G.R., Aeolian sedimentation and bypass, Triassic of Western Canada, Bulletin of Canadian Petroleum geology, 1997, V. 45, pp. 624–642.

2. Davies G.R., Watson N., Moslow T.F., MacEachern J.A., Regional subdivisions, sequences, correlations and facies relationships of the Lower Triassic Montney Formation, west-central Alberta to northeastern British Columbia, Canada – with emphasis on role of paleostructure, Bulletin of Canadian Petroleum Geology, 2018, V. 66, no. 1, pp. 23–92, https://doi.org/

3. Osadetz K.G., Mort A., Snowdon L.R., Lawton D.C., Chen Zh., Saeedfar A., Western Canada sedimentary basin petroleum systems: A working and evolving paradigm, Interpretation 6 (2): SE63–SE98, https://doi.org/10.1190/INT-2017-0165.1

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5. Kent D.M., Paleogeographic evolution of the Cratonic platform - Cambrian to Triassic: edited by Mossop G., Shetson I., In: Geological atlas of the Western Canada Sedimentary Basin: Canadian Society of Petroleum Geologists and Alberta Research Council, 1994, pp. 69–86

6. Alberta geological survey. Alberta table of formations, URL: https://ags.aer.ca/publication/alberta-table-formations

7. Henderson C.M., Richards B.C., Barclay J.E., Permian strata of the Western Canada sedimentary basin, Geological atlas of the Western Canada sedimentary basin: Canadian Society of Petroleum Geologists and Alberta Research Council, 1994, pp. 251–259.

8. Utting J., Zonneveld J.-P., MacNaughton R.B., Falls K.M., Palynostratigraphy, lithostratigraphy and thermal maturity of the Lower Triassic Toad and Grayling, and Montney formations of Western Canada and comparisons with coeval rocks of the Sverdrup Basin, Nunavut, Bulletin of Canadian Petroleum Geology, 2005, V. 53, pp. 5–24.

9. Zonneveld J.-P., Moslow Th.F., Paleogeographic setting, lithostratigraphy, and sedimentary framework of the Lower Triassic Montney Formation of western Alberta and northeastern British Columbia, Bulletin of Canadian Petroleum Geology, 2018, V. 66, no. 1, pp. 1–35.

10. Wood J.M., Water distribution in the Montney tight gas play of the Western Canadian sedimentary basin: Significance for resource evaluation, SPE Reservoir Evaluation & Engineering, https://doi.org/10.2118/161824-PA.

11. Wirth O., Bastian P., Reservoir characterization of the Montney in Blair/Kobes area of NE BC, Proceedings of the 5th Unconventional Gas Technical Forum, Victoria, 2011, URL: http://www.ugresources.com/linkclick.aspx?fileticket=CP1Hic3pfR0%3D&amp;tabid=2932.

12. Rakhit K., The Montney resource play - limits and distribution, a hydrodynamic perspective, Proceedings of 4th Annual Unconventional Gas Technical Forum, Victoria, 2010.

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14. Podetz, C.P., Western Canada activity summary: Montney. Getting Deeper into the play, Discovery Digest, 2019, January 9.

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The article presents the results of studies of the Ural folded system, located in the articulation zone of the Pre-Ural regional trough and the West Ural outer folding zone, based on a statistical study of the organic matter of Silurian rocks and modeling the processes of generation, migration, accumulation, conservation, destruction and redistribution of hydrocarbons in geological time. The study area has a high oil and gas potential. Despite the difficulties of studying the bottoms of Paleozoic deposits, it is these deposits that are of interest from the point of view of the prospects for oil and gas content. In the geochemical analysis, statistical processing of the previously obtained pyrolysis results according to the Rock-Eval method of Silurian parent rocks was carried out, the generation potential was determined. Four proven generational-accumulation systems were modeled: cisuralian Permian, Visean-Bashkirian, Fransian-Tournaisian, Lower Devonian-Fransian, and one supposed Silurian system. In thermobaric analysis, the distribution of the geothermal gradient, the distribution zones of abnormal pore pressures, hydrostatic pressures, and water pressure regimes have been studied. A comparative analysis of migration-accumulation processes within the study area in fluid-conducting and fluid-conducting faults was carried out. The distribution of hydrocarbon resources by area coincides with the fields known to date, which indicates the reliability of the constructed geological model. The results of the research will contribute to the understanding of a single picture of the formation of accumulations of oil and gas, as well as to assess the impact of the alleged sources of hydrocarbons in the region; identify the foci of hydrocarbon generation, develop and expand opportunities in solving urgent problems of localization and spatial distribution of hydrocarbon raw materials in traps, as well as revise the resources regional assessment.

References

1. Monakova A.S., Osipov A.V., Bondarev A.V. et al., Geokhimicheskaya kharakteristika neftematerinskikh porod yuzhnoy chasti predural'skogo progiba, otsenka realizatsii siluriyskikh porod (Geochemical characteristics of oil-bearing rocks of the southern part of the pre-Ural depression, assessment of the realization of Silurian rocks), Proceedings of 9th International Geological and Geophysical Conference EAGE “Sankt-Peterburg 2020. Geonauki: transformiruem znaniya v resursy” (St. Petersburg 2020. Geosciences: transforming knowledge into resources), Moscow, 2020, p. 120.

2. Osipov A.V., Bondarev A.V., Mustaev R.N. et al., Results of geological survey in the eastern side of the southern part of the Pre-Urals foredeep (In Russ.), Izvestiya vysshikh uchebnykh zavedeniy. Geologiya i razvedka, 2018, no. 3, pp. 42–50.

3. Bondarev A.V., Dantsova K.I., Barshin A.V., Minligalieva L.I., Modeling maturity of organic matter in source rocks of silurian oil and gas source strata of Southern Urals based on statistical processing of Rock-Eval results (In Russ.), Trudy Rossiyskogo gosudarstvennogo universiteta nefti i gaza imeni I.M. Gubkina, 2020, no. 1(298), pp. 29–37, https://doi.org/10.33285/2073-9028-2020-1(298)-29-37

4. Bondarev A.V., Barshin A.V., Dantsova K.I., Minligalieva L.I., Modelirovanie katageneticheskogo preobrazovaniya neftegazomaterinskikh tolshch na osnove statisticheskoy obrabotki piroliticheskikh rezul'tatov (Yuzhnoe Predural'e) (Modeling of catagenetic transformation of oil and gas reservoirs on the basis of statistical processing of pyrolytic results (Southern Pre-Urals)), Proceedings of IX International Scientific Conference of Young Scientists “Molodye – Naukam o Zemle” (Young - Science of the Earth), Moscow, 2020, pp. 269–270.

A great number of space images of the Caspian syneclise taken from various space carriers is currently available for free. The article presents a decryption scheme made using 37 images covering the entire territory of the Caspian Sea. Shooting conditions were selected as cloudless as possible. The season was spring. A mosaic of thermal images has been assembled from individual images with the use of the QGIS program. The decryption schemes analysis was carried out for the period from 1973 to 2021. An expert (author's) decoding was also carried out to identify the geomorphological and landscape features of the most common lineaments. As stated in this paper, lineaments are straightened and (or) linearly organized elements of the image of natural genesis. Numerous circular photoanomalies of various severity and size were also distinguished during visual decoding. Large numbers of local phototone and photo pattern anomalies were highlighted in the images, indicating the position of the salt domes of the Caspian Sea and brachyanticlines spread within the adjacent territories. Comparison of the lineaments deciphered in this work with previously compiled maps showed that almost all objects identified earlier are depicted on satellite images, but previously unknown ones are also highlighted. Particular attention in this work is paid to the identified intersections of lineaments since they are often the indicators of the highest permeability of the lithosphere. Mineral deposits, including hydrocarbons, are most often associated with them. The resulting diagram compiled according to the results of computer and expert decryption shows previously uncharted lineaments.

References

1. Orudzheva D.S., Vorob’ev V.T., Romashov A.A., Aerokosmicheskie issledovaniya neftegazonosnykh territoriy Prikaspiyskoy vpadiny (Aerospace studies of oil and gas bearing areas of the Caspian basin), Moscow: Nauka Publ., 1982, 76 p.

2. Ramberg H., Gravity, deformation and the earth’s crust, London, New York: Academic P., 1967.

3. Kornienko S.G., Vozmozhnosti i perspektivy primeneniya metodov teplovogo distantsionnogo zondirovaniya v neftegazovoy otrasli (Possibilities and prospects of application of methods of thermal remote sensing in the oil and gas industry), Collected papers “Nauka i tekhnika v gazovoy promyshlennosti” (Science and technology in the gas industry), 2002, pp. 8–14.

4. Trofimov D.M., Distantsionnye metody v neftegazovoy geologii (Remote sensing methods in oil and gas geology), Moscow: Infra-Inzheneriya Publ., 2018, 388 p.

5. Shilkin A.N., Kosmicheskaya geoskopiya kak metod izucheniya glubinnoy struktury: na primere Prikaspiyskoy vpadiny (Space geoscopy as a method of studying the deep structure: on the example of the Caspian basin), Saratov: Publ. of Saratov university, 1982, 129 p.

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8. Miloserdova L.V., Dantsova K.I., Khafizov S.F., Connection of lineaments and nodes of their intersections with the oil and gas content of the Caspian syneclise and its framing (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 6, pp. 22–26, https://doi.org/10.24887/0028-2448-2021-6-22-26

The present time is a turning point in teaching due to the active introduction of computer technologies in education. This is especially true for teaching geological decoding as a result of the availability of satellite images and methods of their processing. With the advent of satellite images, it turned out that previously unknown formations are widely developed on Earth – lineaments and ring structures, the nature of which in some cases has not yet been deciphered. The article reflects the long-term experience of teaching the discipline Aerospace Methods in Oil and Gas Geology in the fifth year at Gubkin Russian State University of Oil and Gas. The principles and techniques of teaching this discipline in oil and gas geology are highlighted for the first time. The content (traditional course – lectures and practical tasks related to their topics) and methods of teaching the discipline, as well as control measures are described. Practical tasks are grouped into four blocks. The work is carried out using open access resources GoogleEarth, QGIS. Course design is possible in the course. The article discusses the possibilities of distance teaching of the discipline. Special attention is paid to the role of the hydro grid pattern in the decryption of structures. It is concluded that the use of images in oil and gas geology helps not only to solve highly specialized tasks, but also allows you to see and solve geological, predictive and prospecting problems in their unity and the relationship of parts. Recommendations on the educational literature for this discipline are given. The universality of space images is discussed (depending on the research objectives various data can be extracted from them).

References

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5. Korchuganova N.I., Korsakov A.K., Distantsionnye metody geologicheskogo kartirovaniya (Remote methods of geological mapping), Moscow: KDU Publ., 2009, 288 p.

6. Kats Ya.G., Tevelev A.V., Poletaev V.I., Osnovy kosmicheskoy geologii (Fundamentals of space geology), Moscow: Nedra Publ., 1988, 236 p.

One of the most important issues in petroleum geology is related to the processes of hydrocarbon generation and accumulation at great depths. The Caspian basin is one of the most promising objects in terms of oil and gas potential at great depths. To date, the processes of hydrocarbon formation in subsalt strata have been poorly studied in this region, but are of high interest. The generating rocks of the Caspian sea region are considered to be terrigenous, siliceous-carbonate deposits of Devonian-Carboniferous age and Permian carbonate- argillaceous deposits in the depth range from 4 to 5 km with sapropelic-humus type of organic matter.

The article considers the generation potential, determined using the Rock-Eval method, of the main generating strata in the Caspian basin - Devonian, Lower Carboniferous, Middle-Upper Сarboniferous, Lower Permian deposits. The core was studied from a well located on the Eastern side of the Caspian Basin, in the Aktobe region. In this area, such studies were conducted for the first time. The analysis of 15 rock samples was carried out by the Rock-Eval method with further interpretation. The position of most stratigraphic boundaries in the well could not be established reliably, so they were established conditionally based on geophysical data. As a result, oil and gas source rocks were identified in the section of the well characterized by II, II-III and III types of kerogens. Some of the samples in the well were immature. The article presents modified Van Crevelin diagrams, a graph of the dependence of the kerogen productivity index on Tmax, a graph of the dependence of the total organic carbon content (TOC) on the generation potential of the rock (S1+S2).

References

1. Iskaziev K.O., Strategiya osvoeniya resursov nefti i gaza v podsolevykh otlozheniyakh severa Prikaspiyskoy sineklizy (Strategy for the development of oil and gas resources in the subsalt deposits of the northern Caspian syneclise): thesis of doctor of geological and mineralogical science, Moscow, 2021, URL: https://www.gubkin.ru/diss2/files/d2-iskaziev-ko/Dissertation_Iskaziev_KO.pdf

2. 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, pp. 3–19, https://doi.org/10.54859/kjogi.202023.

3. 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.

4. Murzin Sh.M., Geological history and petroleum systems of the North Caspian Sea (In Russ.), Vestnik Moskovskogo universiteta. Ser. 4. Geologiya, 2010, no. 6, pp. 23-35

Recently, the issues of degassing of the subsurface, especially in connection with the problems of formation of hydrocarbon deposits and global warming, have been the area of close attention of researchers. Numerous works and scientific conferences are devoted to this problems. The most famous ways of concentrated degassing are volcanoes and mud volcanoes. However, the issue of observation and fixation of scattered paths of degassing of the Earth has been developed to a much lesser extent. Nevertheless, there is a group of methods optimally adapted for detecting such phenomena — remote sensing, which covers a number of areas of science and technology that have developed for more than a hundred years. Gases released from the subsurface are primarily hydrogen, carbon monoxide, methane, helium and to a lesser extent others. A huge number of degassing structures have been found in various parts of the world, which can be traced using satellite images. The prospects for increasing the efficiency of using aerospace monitoring methods to solve the problems of the oil and gas complex are associated with the development and use of new methods, technologies and equipment for remote sensing, aerospace information processing, the use of modern geoinformation technologies, as well as the integration of aerospace and ground data. There are different opinions about the source of deep gases, the forms of their release, ways and methods of ascent to the daytime surface. For remote detection of surface gas phenomena, multispectral remote sensing data of medium resolution are best suited. The article uses materials from the public resources EarthExplorer (USGS), Google Maps, Google Earth, Google Earth Engine Datasets.

References

1. Aerokosmicheskiy monitoring ob”ektov neftegazovogo kompleksa (Aerospace monitoring of oil and gas facilities): edited by Bondur V.G., Moscow: Nauchnyy mir Publ., 2012, 558 p.

2. Bondur V.G., Kuznetsova T.V., Vorob’ev V.E., Zamshin V.V., Detection of gas shows (gas seeps) on the russian shelf using satellite data (In Russ.), Georesursy, geoenergetika, geopolitika, 2014, no. 1 (9), pp. 1–23.

3. Lein A.Yu., Ivanov M.V., Biogeokhimicheskiy tsikl metana v okeane (Biogeochemical cycle of methane in the ocean), Moscow: Nauka P publ., 2009, 576 p.

4. Miloserdova L.V., Aerokosmicheskie metody v neftegazovoy geologii (Aerospace methods in petroleum geology), Moscow: Nedra Publ., 2022.

5. Kol’tsevye struktury: illyuziya ili real’nost’ (Ring structures: illusion or reality), URL: http://miloserdovalv.narod.ru/zagruzki/airo/2018/9-kolcevye_struktury.pdf

6. Vodorodnaya degazatsiya na Russkoy platforme (Hydrogen degassing on the Russian platform), URL: https://earth-chronicles.ru/news/2011-07-03-2780

7. Kerimov V.Yu., Guliev I.S., Osipov A.V. et al., Mud volcanism and ultra-deep hydrocarbon systems (In Russ.), Aktual’nye problemy nefti i gaza, 2018, no. 4(23), pp. 1–9.

8. Krupskaya V.V., Andreeva I.A., Sergeeva E.I. et al., Gryazevoy vulkan Khaakon Mosbi (Norvezhskoe more): osobennosti stroeniya i sostava otlozheniy (Mud volcano Haakon Mosby (Norwegian Sea): features of the structure and composition of sediments), Collected papers “Opyt sistemnykh okeanologicheskikh issledovaniy v Arktike“ (Experience of systemic oceanological research in the Arctic), Moscow: Nauchnyy mir Publ., 2001, pp. 492–502.

9. Bogoyavlenskiy V.I., Bogoyavlenskiy I.V., Kishankov A.V., Yanchevskaya A.S., Gas hydrates in the Circum-Arctic Region aquatories. Arctic: ecology and economy (In Russ.), Arktika: ekologiya i ekonomika, 2018, no. 3(31), pp. 42-55, https://doi.org/10.25283/2223-4594-2018-3-42-55

10. Ratner S.V., Investigation of mud volcanoes in the Black Sea for safety of navigation and underwater systems (In Russ.), Zashchita okruzhayushchey sredy v neftegazovom komplekse, 2007, no. 10, pp. 6–10.

11. URL: https://earthexplorer.usgs.gov/

12. Rudenko A.V., Metodika pryamogo deshifrirovaniya kol’tsevykh struktur vodorodnoy degazatsii na territoriyakh prozhivaniya lyudey i vedeniya khozyaystva po dannym Google Maps i Google Earth (In Russ.), Geopolitika i ekogeodinamika regionov, 2019, V. 5(15), no. 3, pp. 326–334.

13. Sokol E.V., Kokh S.N., In the reflections of “eternal lights” (In Russ.), Nauka iz pervykh ruk, 2010, V. 35, no. 5, URL: https://scfh.ru/papers/v-otbleskakh-quot-vechnykh-ogney-quot/

The paper presents the results of interpretation of 488 samples examined by the pyrolytic Rock-Eval method, of which 69 are from the Bazhenov formation, 12 from the Togur formation and 407 from the Tyumen formation. The research region is the south of the West Siberian oil and gas province (12 areas). Other Rock-Eval pyrolysis data were also used to characterize the potential of oil-producing rocks to the fullest extent. Correct interpretation can be performed for samples not contaminated with migratory hydrocarbons. The description of samples of a part of the studied areas is presented. A detailed study of the area is due to the significant prospect of its oil and gas potential. The content of organic carbon, the stages of thermal maturity, the type of kerogen and the generation potential for the parent rocks of the Togur, Tyumen and Bazhenov formations were determined. The main purpose of this study is to determine the quality of kerogen and the amount of organic matter. The organic matter dispersed in the rock for the samples of the Tyumen formation corresponds in composition to kerogen of type II, III. In the Van Crevelin diagram, most of the points of the Togur formation are grouped between the evolution curves of kerogens of the second and third types; this indicates a possible mixing of the two types of kerogen. The generation potential of the rocks of the Tyumen formation varies from "poor" to "excellent". The generation potential of the samples of the Togur formation (for all studied areas) varies from average to very good. The generation potential of the Bazhenov formation varies from very good to excellent. The variety of conditions for the accumulation of organic matter increases to the east of the research area. The content of organic matter and its quality make us believe that conditions favorable for the formation of deposits persist throughout the section, gradually deteriorating towards the east.

References

1. Peters K.E., Cassa M.R., Applied source rock geochemistry, AAPG Memoir 60, 1994, pp. 93–120.

2. Dembicki H. Jr., Three common source rock evaluation errors made by geologists during prospect or play appraisals, AAPG Bulletin, 2009, V. 93, no. 3, pp. 341–356, https://doi.org/10.1306/10230808076

3. Peters K.E., Walters C.C., Moldowan J.M., The Biomarker guide, V. 1. Biomarkers and isotopes in the environment and human history, V. 2. Biomarkers and isotopes in petroleum exploration and earth history, United Kingdom at the Cambridge University Press, 2005, 1132 pp.

4. Dantsova K.I., Khafizov S.F., Geochemical characteristics of the organic matter of the Jurassic sediments of the southern regions of Western Siberia (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 5, pp. 50–53, DOI: https://doi.org/10.24887/0028-2448-2021-5-50-53

The Lower Cambrian halogen-carbonate deposits are currently the most promising for the search for oil and gas objects within the Nepa-Botuba anteclise. The article describes methodical techniques for detailed well log correlation of complicated by trap magmatism log using the Yaraktinskoye field as an example. At the first stage of the research in the studied section of the well, all intervals with recorded magma definition were excluded. It was performed correlation of sections of wells treated in this way. The main features of the block structure of the studied objects before the introduction of trap intrusions are rarely revealed by the nature of the change in the thickness of the members. The effectiveness of this technique increases with the repetition of sequential paleoprofiling. When leveling to the reference boundary, it was established that the formation of the Lower Cambrian deposits in the territory of the Yaraktinskoye field is associated with the ‘keyboard’ subsidence of blocks along consedimentary faults. At the second stage, the well sections were correlated with restored intrusions. The results confirmed the presence of previously detected ruptures of infectious diseases. Based on well data only as an example, using the method of sequential paleoprofiling it was shown that the formation of the Lower Cambrian halocarbonate sequences occurred due to the subsidence of adjacent blocks along consedimentary faults. These faults subsequently became possible ways for the intrusion of trap magmatism into sedimentary rocks. It is concluded that, despite the multiplicity of samples and sampling algorithms, it is necessary to find a direction in scientific and methodological development, especially in the study of complex reservoirs.

References

1. Tonkikh M.E., Baryshev A.S., Egorov K.N., Koshkarev D.A., Structural position of traps in the south of Siberian platform (In Russ.), Vestnik IrGTU, 2011, no. 12(59), pp. 65–73

2. Rapatskaya L.A., Tonkikh M.E., Strizhakov E.A., Trap magmatism effect on oil and gas horizons (south of the Siberian platform) (In Russ.), Izvestiya Sibirskogo otdeleniya Sektsii nauk o Zemle RAEN. Geologiya, razvedka i razrabotka mestorozhdeniy poleznykh iskopaemykh, 2019, V. 42, no. 1, pp. 7–14.

3. Shemin G.G., Geologiya i perspektivy neftegazonosnosti venda i nizhnego kembriya tsentral'nykh rayonov Sibirskoy platformy (Nepsko-Botuobinskaya, Baykitskaya anteklizy i Katangskaya sedlovina) (Geology and oil and gas potential Vendian and Lower Cambrian deposits of central regions of the Siberian Platform (Nepa-Botuoba, Baikit anteclise and Katanga saddle)): edited by Kashirtsev V.A., Novosibirsk: Publ. of SB RAS, 2007, 467 p.

4. Gutman I.S. et al., Korrelyatsiya razrezov skvazhin slozhnopostroennykh neftegazonosnykh ob"ektov i geologicheskaya interpretatsiya ee rezul'tatov (Correlation of well sections of complex oil and gas objects and geological interpretation of its results), Moscow: ESOEN Publ., 2022, 336 p.

One of the priority areas for hydrocarbon production in Surgutneftegas PJSC is the complex productive layers of the Middle Jurassic complex, which have significant prospects for the discovery of new hydrocarbon deposits in Western Siberia. The rocks of the Tyumen formation are characterized by sharp lithological and facies variability, low filtration and capacitance properties and are not always controlled by structural factors. The zones of improved reservoirs are mainly confined to riverbed or delta formations. Despite the considerable amount of accumulated information, the models of the rocks of the Tyumen formation are still quite conditional and are created with large assumptions and simplifications. Detailed seismic exploration of MCDP 3D copes well enough with the identification of various fluvial-type objects, depending on the quality of the field and processed seismic material, but for successful drilling, it is sometimes not enough to determine only the boundaries of river facies. It is necessary to determine the facies feature of channel bodies, rank them according to their fishing properties: identify low-permeable areas, map the areas of improved filtration and capacitance properties, thereby increasing the efficiency of exploration.

The article considers the method of mapping highly permeable reservoirs in the continental sediments of the Tyumen formation, based on the dynamic and kinematic parameters of the wave field, taking into account the facies features of the formation development. The archive seismic data of MCDP 3D of different years were re-processed with an emphasis on the Tyumen section interval and the direct participation of interpreters at each stage of processing, which allowed to map new promising objects. According to the obtained volume, paleotectonic features of the work area, core material were studied, spectral decomposition was calculated, time sections, sedimentation and horizontal sections of the amplitudes cube and αPS were analyzed. The authors mapped objects of riverbed genesis, identified and substantiated desalinated areas with improved filtration and capacitance properties within the boundaries of ancient riverbeds.

References

1. Baraboshkin E.Yu., Prakticheskaya sedimentalogiya. Terrigennye rezervuary (Practical sedimentology. Terrigen collectors), Tver&#39;: GERS Publ., 2011, 152 p.

2. Gogonenkov G.N. et al., Sedimentation seismic data analysis technology (InRuss.), Neft&#39;.Gaz. Novatsii, 2017, no. 1, pp. 62–69.

3. Kontorovich A.E., Kontorovich V.A., Ryzhkova S.V. et al., Jurassic paleogeography of the West Siberian sedimentary basin (In Russ.), Geologiya I geofizika = Russian Geology and Geophysics, 2013, V. 54, no. 8, pp. 972–1012.

4. Surkov V.S. et al., Nizhne-sredneyurskie otlozheniya Zapadno-Sibirskoy plity, osobennosti ikh stroeniya i neftegazonosnost (Lower-Middle Jurassic deposits of the West Siberian Plate, features of their structure and oil and gas content), Collected papers “Teoreticheskie regional&#39;nye problemy geologii nefti i gaza” (Theoretical regional problems of oil and gas geology), Novosibirsk: Nauka Publ., 1991, pp. 101–110.

Geological features of the field regarded in this article require the active application of modern integrated methods for maintenance and construction of high-tech wells. An increase in drilling efficiency improves the profitability of field development and the development of hard-to-recover reserves. Drilling efficiency is proposed to be ensured by complex of methods: geomechanical calculations in real time using geological steering data; cavernosity analysis of the well, taking into account the peculiarities of drilling and lithotypes; evaluation of the geometry of the borehole. Studies have shown that the clays in the upper part of the target formation are most significantly affected by the time factor and pooling out of hole with back-reaming, which contribute to an increase in the vugginess of the borehole. Taking into account geological features during drilling allows accurately adjust the wellbore stability model and the intervals of potential complications by promptly updating the geomechanical model in real time with recommendations. Geomechanical modeling allows to predict a safe drilling window. Reducing the drilling time of the production liner and minimizing the open state of the borehole due to the maximum approximation of the landing depth of the column shoe to the roof of the target formation, as well as minimizing departures into clay intervals during wiring reduces the risks of differential sticking and collapse. Geological steering support provides an increase in the reliability of the analysis of complications and gives a more complete picture during the well construction, which increases the likelihood of making optimal decisions in the future. Monthly updating of the hydrodynamic model for the target reservoir is necessary for the correct assessment of the stress state, selection of the optimal density of the drilling fluid and reduction of the risk of differential sticking. Using the well complexity index allows to evaluate and plan the necessary procedures for the successful construction of a well in similar conditions. The results obtained show that the implementation of recommendations and measures based on geomechanical modeling can ensure the safe construction of a well on the drilled area.

References

1. Kayurov N.K., Dontsov E.N., Lyudinovets A.M. et al., NNTC Research & Development Center: Integrated LWD, mud logging and geomechanical surveys while drilling in the Nizhnevartovsk district (In Russ.), ROGTEC Rossiyskie neftegazovye tekhnologii, 2018, V. 52, pp. 100–109.

2. Gabitov S.I., Gotsulyak A.S., Chebyshev I.S., Mukhamadiev R.V., Support of drilling high-technological wells based on the integration of geomechanics and geosteering (In Russ.), Neftegazovoe delo, 2020, V. 18, no. 2, pp. 15–23,  https://doi.org/10.17122/ngdelo-2020-2-15-23

3. Hamid O., Qahtani A., Alamer S., Sherbeny W., Mitigating wellbore stability risks through geomechanical solutions, SPE-192872-MS, 2018, https://doi.org/10.2118/192872-MS

4. Toropetskiy K.V., Kayurov N.K., Ul’yanov V.N., Borisov G.A., Modeling support for horizontal drilling in Eastern Siberia (In Russ.), ROGTEC Rossiyskie neftegazovye tekhnologii, 2017, V. 48, pp. 76–87.

5. Godwin C., Jacob N., Bariakpoa K., Samuel N., Evaluation of optimum mud weight window for prevention of wellbore instability in Niger Delta wells, IOSR Journal of Engineering, 2020, V. 10, no. 10, pp. 61 – 66.

6. Salim A., Qasim H., Rajeev R. et al., Successful drilling campaign of high angled wells in tight gas fields using 3D geomechanical modeling and real-time monitoring, SPE-202123-MS, 2021, https://doi.org/10.2118/202123-MS

7. Guifen X., Draoui E.H., Jamal R. et al., Geomechanics characterization of Nahr Umr and Laffan Shales through anisotropic geomechanics and shale stability analysis for drilling optimization, SPE-202933-MS, 2020, https://doi.org/10.2118/202933-MS

8. Al Enezi D., Al Hajeri M., Gholum S. et al., Realtime drilling geomechanics aids safe drilling through unstable shales and Channel sands of Wara formations, Minagish field, West Kuwait, SPE-200929-MS, 2021, https://doi.org/10.2118/200929-MS.

9. Chettykbayeva K., Petrakov Y., Sobolev A. et al.,  The strategic and tactical value of geomechanics for drilling operational excellence of ERD well in Uzen field, SPE-191632-18RPTC-MS, 2018, https://doi.org/10.2118/191632-18RPTC-MS

10. Al Bahrani H., Al Yami A., Drillstring vibrations and wellbore quality: Where drillstring design meets geomechanics, SPE-193253-MS, 2018, https://doi.org/10.2118/193253-MS

11. Karimi M., Drill-cuttings analysis for real-time problem diagnosis and drilling performance optimization, SPE-165919-MS, 2013, https://doi.org/10.2118/165919-MS

12. Renato G., Zuly H., Yair A., New approach for estimating cavings volume to avoid wellbore instabilities, Proceedings of Rock Mechanics for Natural Resources and Infrastructure-ISRM Specialized Conference, Goiania, Brazil, 2014,  URL: https://www.researchgate.net/publication/335189023

13. Ortenzi L., Evans M., Maeso C.J., An integrated caliper from neutron, density, and ultrasonic azimuthal LWD data, SPE-77479-MS, 2002, https://doi.org/10.2118/77479-MS

14. Nadir A., Bachir G., Laid S. et al., Effective solutions to well integrity management using multi finger caliper and electromagnetic tool, SPE-198570-MS, 2019, https://doi.org/10.2118/198570-MS.

15. Monali L., Jayabrata K., Pankaj S. et al., Managing multidimensional constraints to drill ERD wells in Rajasthan with high directional difficulty index (DDI), SPE-178073-MS, 2015, https://doi.org/10.2118/178073-MS.

The Priobskoye field is currently one of the largest unconventional reservoirs in the West Siberia. That field is characterized by low permeability and complex reservoir structure. In order to increase the recovery factor and raise the level of oil production in the Priobskoye tight formation the amount of wellworks constantly increases. Reservoir fracturing is the main of the variety of different wellworks is applied in this oilfield. The first operation of hydraulic fracturing at the Priobskoe field was made in 1992. RN-Yuganskneftegas LLC is one of the leaders in the field of hydraulic fracturing. Petroleum engineers, who develop this oil reservoir, have a great practical experience in reservoir fracturing. Nowadays formation fracturing is used in all well completing operations at the Priobskoye field.

This article represents the main stages of evolution of hydraulic fracturing technology at the Priobskoye field. Historical data of the number of performed well operation of hydraulic fracturing at the Priobskoye field are presented. The relation between a volume of injection proppant and performance wells (vertical, horizontal) after hydraulic fracturing was discovered and the analysis of refracturing treatment effectiveness was made additionally. The ideas for further optimization of hydraulic fracturing technologies and development of digital hydraulic fracturing modeling are presented.

References

1. Yanin A.N., Hydraulic fracturing is a breakthrough technology! To the 30th anniversary of the beginning of the massive application of hydraulic fracturing in the fields of Western Siberia (In Russ.), Burenie i Neft', 2018, no. 7, pp. 20–27.

2. Kolupaev D.Yu., Bikkulov M.M., Solodov S.A. et al., Mass hydraulic fracturing is a key technology of the southern part Priobskoye field development (In Russ.), PROneft', 2019, no. 1, pp. 39–45, https://doi.org/10.24887/2587-7399-2019-1-39-45

4. Fakhretdinov I.V., Integrated monitoring of horizontal wells with multistage hydraulic fracturing at the implementation stage within the priobskiy oil field for their work effectiveness (In Russ.), Problemy sbora, podgotovki i transporta nefti i nefteproduktov, 2017, no. 4, pp. 92–99.

5.  Aksakov A.V., Borshchuk O.S., Zheltova I.S. et al., Corporate fracturing simulator: from a mathematical model to the software development (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2016, no. 11, pp. 35–40.

The paper presents a research of the process of the carbonate reservoir developing with a fractured-cavernous capacity on the example of the Yurubcheno-Tokhomskoye oilfield of the Krasnoyarsk region. The carbonate reservoir of the Riphean deposits, composed mainly of dolomite, forms a low-permeability matrix with a system of micro- and macro fractures and caverns, with the capacity of less than 2%. A system of subvertical fractures connects extensive gas cap, oil-saturated layer and aquifer, which leads to exploitation complications such as a gas and water breakthroughs. Additionally it is causes the low efficiency of a formation pressure maintenance system by water injection. Two points of water injection into Riphean deposits are organized at the field for produced water utilization, but this does not have a significant effect on reservoir pressure. An excess drop in reservoir pressure accompanies the start of commercial development and the intensification of oil production. The analysis of production data showed that the decline rate reservoir pressure is directly related to the increase in gas cap gas production. The paper considers an approach to stabilizing the energy state of the reservoir by balancing the extraction of oil and gas. A research program was implemented, during which an evaluation of changes in reservoir pressure, gas-oil ratio and the decline oil production rate when limiting associated petroleum gas was made. It is shown how the control of the gas extraction rate by well shutdown with a high gas-oil ratio makes it possible to compensate for the loss of oil production and obtain positive effect on the cumulative oil production.

References

1. Bagrintseva K.I., Krasil'nikova N.B. et al., Formation conditions and properties of the Riphean carbonaceous reservoirs of the Yurubcheno-Tokhomsk deposit (In Russ.), Geologiya nefti i gaza, 2015, no. 1, pp. 24–40.

2. Kiselev V.M., Kozyaev A.A., Korotysheva A.V., Analysis of natural fracturing systems of the Yurubcheno-Tokhomskoye field (In Russ.), Tekhnologii nefti i gaza, 2018, no. 6, pp. 22–25.

3. Kontorovich A.E., Izosimova A.N., Kontorovich A.A. et al., Geological structure and formation conditions of the giant Yurubcheno-Tokhomskaya zone of oil and gas accumulation in the Upper Proterozoic of the Siberian Platform (In Russ.), Geologiya i geofizika = Russian Geology and Geophysics, 1996, V. 7, no. 8, pp. 166-195.

4. Kutukova N.M., Birun E.M., Malakhov R.A. et al., The conceptual model of Riphean carbonate reservoir in Yurubcheno-Tokhomskoye field (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2012, no. 11, pp. 4-7.

5. Kutukova N.M., Productivity criteria of the riphean deposits of the Yurubchen-Tokhomo zone of oil and gas accumulation according to a complex of geological and geophysical data (In Russ.), Aktual'nye problemy nefti i gaza, 2019, no. 3(26),  https://doi.org/10.29222/ipng.2078-5712.2019-26.art9

6. Kutukova N.M., Shuster V.L., Pankov V.M. et al., Integrated approach to the modeling of the carbonate reservoir with complicated trap structure in Eastern Siberia (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 11, pp. 23-27, https://doi.org/10.24887/0028-2448-2019-11-23-27

7. Kutukova N.M., Pankov M.V., Sorokin A.S., Kozyaev A.A., Optimization of the development system of the Yurubcheno-Tokhomsky field based on the conceptual geological model (In Russ.), Tekhnologii nefti i gaza, 2019, no. 6, pp. 57-67, https://doi.org/10.32935/1815-2600-2019-125-6-57-614–79

8. Reiss L.H., Reservoir engineering aspects of fractured formations, Atlasbooks Dist Serv, France, 1980.

9. Osipenko A.A., Boykov O.I., Nazarov D.V. et al., Practical aspects of the identification of the void space of cavern-and-fracture reservoirs in conditions of an extremely low porosity (In Russ.), Karotazhnik, 2019, no. 6(300), pp. 134-144.

10. Sautkin R.S., Reservoir properties and productivity of Riphean deposits in Yurubcheno-Tokhomsky field (In Russ.), Georesursy, 2015, no. 4, pp. 25–34.

11.  Tikhonova K.A., Kozyaev A.A., Nazarov D.V. et al., Multi-disciplinary approach for identifying and forecasting high-porosity vuggy zones in the Riphean reservoir of the Yurubcheno-Tokhomskoye field (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 12, pp. 74–79, https://doi.org/10.24887/0028-2448-2020-12-74-79

A large amount of data is accumulating during the exploitation of oil wells. The data characterize the operating mode and properties of the extracted raw materials. It is not always use in a systematic and objective way, and not all possibilities for their application have been explored. The work is aimed at obtaining an understanding of the possible use of an array of such data to analyze the state of the well and predict the timing when an accident may occur. Relevant data were selected and a comparative analysis of operating parameters before failures and parameters in normal operating modes was carried out. There is a correlation between the characteristics of the well operating mode and the probability of failures (in particular, due to production casing leaks, etc.). The output results of machine learning algorithms for the separation of emergency and normal operating states were analyzed. It is shown how the trained algorithms work on the entire period of well operation (presented in the data and excluded from training). A typical picture of daily forecasts of production casing leaks type pre-emergency states on wells where such failures were occurred is very different from normal operating wells. There are a series of positive predictions over long intervals until a production casing leak is detected. The article proposes an evaluation of the results at different time intervals and a possible interpretation for use in production. Many of the other failures intersect or overlap each other, which makes it difficult to perform a multi-class separation and unambiguous conclusions about the effectiveness of their prediction. The presented results, at least in part, can clarify the issue of the probability and timing of failures and be used in the oil production monitoring.

References

1. Salehi S., Hareland G., Khademi K. et al., Casing collapse risk assessment and depth prediction with a neural network system approach, Journal of Petroleum Science and Engineering, 2009, V. 69, no. 1–2, pp. 156–162, https://doi.org/10.1016/J.PETROL.2009.08.011

2. Song X., Liu Y., Xue L. et al., Time-series well performance prediction based on Long Short-Term Memory (LSTM) neural network model, Journal of Petroleum Science and Engineering, 2020, V. 186, https://doi.org/10.1016/j.petrol.2019.106682

Prediction of the phase state of multicomponent hydrocarbon systems containing water is an important aspect in modeling technological processes of field development. The presence of water in the composition of the extracted products can have a significant impact on the phase state, as well as on the numerical parameters of PVT properties. This can lead to a violation of the operating modes of the equipment, up to the occurrence of emergency situations. Modeling the phase state of multicomponent systems containing water or other polar substances requires the expansion of existing computational techniques and the development of new ones. The use of cubic equations of state is a generally accepted technique for modeling technological processes accompanying the development of deposits. One of the ways to expand the applicability of cubic equations of state for modeling systems containing polar molecules, such as water or alcohols, is the use of non-standard mixing rules, such as Kabadi – Danner, Huron – Vidal, etc., allowing for mutual dissolution of components in phases. The correct determination of the phase state, phase compositions, as well as PVT properties of hydrocarbon systems allows you to choose the optimal modes of operation of the equipment.

This paper presents the calculation method results of calculations of the phase equilibrium of multicomponent hydrocarbon systems containing water or other polar molecules. The results of a number of works are taken as a basis for calculating the equilibrium of binary systems "gas – water". An extension of the methodology has been carried out for the possibility of calculating the three-phase equilibrium "gas – oil – water" as well as special cases "gas – oil", "gas – water", and "oil – water". A system of equations for calculating phase equilibrium and determining phase fractions is obtained. Corrections for the initial values of the phase equilibrium constants are proposed. The results of calculations are compared with experimental data and the results of calculations in commercial software. Based on the results of the analysis, it is shown that this technique allows obtaining reliable results when modeling phase equilibrium, as well as for solving production problems. The implemented methodology is used in the corporate software complex RN-SIMTEP.

References

1. Yushchenko T.S., Brusilovskiy A.I., Mathematical modeling of PVT-properties of gas condensate systems in contact with residual water in a porous medium (In Russ.), Vesti gazovoy nauki, 2015, no. 4(24), pp. 38-45.

2. Lindeloff N., Michelsen M.L., Phase envelope calculations for hydrocarbon-water mixtures, SPEJ, 2003, V. 9, pp. 298-303, https://doi.org/10.2118/85971-PA

3. Huron M.J., Vidal J., New mixing rules in simple equations of state for representing vapor-liquid equilibria of strongly non ideal mixtures, Fluid Phase Equilibria, 1979, V. 3, pp. 255-271, https://doi.org/10.1016/0378-3812(79)80001-1

4. Il'yasov U.R., Lutfurakhmanov A.G., Efimov D.V., Pashali A.A., Comparative analysis of the properties of hydrocarbon components and fractions in PVT modeling (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 5, pp. 64-67,  https://doi.org/10.24887/0028-2448-2020-5-64-67

5. Brusilovskiy A.I., Fazovye prevrashcheniya pri razrabotke mestorozhdeniy nefti i gaza (Phase transformations in the development of oil and gas fields), Moscow: Graal' Publ., 2002, 575 p.

6. Wang Y., Han B., Liu R., Solubility of CH4 in the mixed solvent t-butyl alcohol and water, Thermochimia Acta, 1995, V. 253, pp. 327-334, https://doi.org/10.1016/0040-6031(94)02011-C

7. Wang L.K., Chen G.J., Han G.H. et al., Experimental study on the solubility of natural gas components in water with or without hydrate inhibitor, Fluid Phase Equilibria, 2003, V. 207, pp. 143-154, https://doi.org/10.1016/S0378-3812(03)00009-8

8. Chapoy A., Coquelet C., Richon D., Solubility measurement and modeling of methane/water binary system at temperatures from 283.15 to 318.15 K and pressure up to 35 MPa, Fluid phase equilibria, 2003, V. 214(1), pp. 101-117, https://doi.org/10.1016/S0378-3812(03)00322-4

9. Culberson O.L., McKetta J.J.Jr., Phase equilibria in hydrocarbon-water systems: III — Solubility of methane in water at pressures to 10,000 psia , Journal of Petroleum Technology, 1951, V. 3, pp. 223-226, https://doi.org/10.2118/951223-G

10. Kim Y.S., Ryu S.K., Yang O., Lee C.S., Liquid water-hydrate equilibrium measurements and unified predictions of hydrate-containing phase equilibria for methane, ethane, propane, and their mixtures, Ind. Eng. Chem. Res., 2003, V. 42, pp. 2409-2414, https://doi.org/10.1021/ie0209374

11. Yang S.O., Cho S.H., Lee C.S., Measurement and prediction of phase equilibria for water + methane in hydrate forming conditions, Fluid Phase Equilibria, 2001, V. 185 pp. 53-63, https://doi.org/10.1016/S0378-3812(01)00456-3

12. Namiot A.Yu., Bondareva M.M., Rastvorimost' gazov v vode pod davleniem (Gas solubility in water under pressure), Moscow: Gostoptekhizdat Publ., 1963, 145 p.

13. Liu Y., Zhu J., Experiment and prediction of water content of sour natural gas with a modified cubic plus association equation of state, Polish Journal of Chemical Technology, 2018, V. 20(2), pp. 98-106, https://doi.org/10.2478/pjct-2018-0029

14. URL: https://www.aspentech.com/en/products/engineering/aspen-hysys

In production fluid snubbing systems of oil production wells equipped by electrical submersible pumps (ESP), non-associated gas usually leads to degradation of flow and pressure performance of the pump. Depending on the amount of non-associated gas in the production fluid flowing through the pump, ESP performance may vary from a slight deterioration to a complete blockage of the liquid phase due to the formation of gas slugs in the inter-blade channels of the pump impellers. The ratio of the volume flow rate of gas bypassing the ESP to the total volume flow rate of non-associated gas before the pump intake is defined as the natural separation factor, and its correct prediction is an important part of designing and optimizing any mechanized method of production fluid lifting. Methods proposed by P.D. Lyapkov, Serrano and Marquez (empirical and mechanistic ones) for calculating natural gas separation ratio in the borehole annular space when the pump takes the gas-liquid mixture above the perforated section of the production string were verified. Mechanistic Marquez method and empirical Serrano method showed calculation accuracy that is acceptable for solving engineering problems. P.D. Lyapkov method and empirical Marquez method showed a significant overestimation of the calculated data over the experimental results. The analytical method for calculating ratio of natural separation of gas was developed for the case of production fluid pumping from the level below the perforation section of the production string. The method involves assumptions (that have been confirmed by numerical experiment) that in the well perforation zone, the reduced fluid and gas velocities and static pressure gradient change linearly along the longitudinal coordinate. Comparison of calculated data obtained by Marquez mechanistic method and the developed analytical method under similar operating conditions showed that lowering the pump below the interval of well perforation provides a more than twofold increase in the natural gas separation ratio.

References

1. Ralph S., Screening possible applications of electrical submersible pumps technology within changing gas oil ratio regimes: Master Thesis, The University of Leoben, 2014.

2. Andriasov R.S., Mishchenko I.T., Petrov A.I. et al., Spravochnoe rukovodstvo po proektirovaniyu razrabotki i ekspluatatsii neftyanykh mestorozhdeniy. Dobycha nefti (Reference guide for the design, development and operation of oil fields. Oil production): edited by Gimatudinov Sh.K., Moscow:  Nedra Publ., 1983, 455 p.

3. Serrano J.C., Natural separation efficiency in electric submersible pump systems: Master Thesis, Tulsa, Oklahoma: The University of Tulsa, 1999.

4. Marquez R., Modeling downhole natural separation: PhD dissertation, The University of Tulsa, 2004.

5. Alhanati F.J.S., Bottomhole gas separation efficiency in electrical submersible pump installation:  Ph. D. Dissertation, Tulsa, Oklahoma: The University of Tulsa, 1993.

6. Sambangi S.R., Gas separation efficiency in electrical submersible pump installation with rotary gas separator: Master Thesis, Tulsa, Oklahoma: The University of Tulsa, 1994.

7. Lackner G., The effect of viscosity on downhole gas separation in a rotary gas separator: Ph. D. Dissertation, Tulsa, Oklahoma: The University of Tulsa, 1997.

8. Wilson B.L., ESP gas separator’s affect on run life, SPE-28526-MS, 1994, https://doi.org/10.2118/28526-MS

9. Pashali A.A., Mikhaylov V.G., Petrov P.V., Mathematical model for natural gas separation factor calculation at creation of reversive liquid current in well punching zone (In Russ.), Vestnik UGATU, 2011, V. 15, no. 2(42), pp. 74–81.

At the late stages of field development, the issues of optimizing well oil production become topical. Artificial oil lift is the most energy-intensive process in an oil field. On the territory of the Perm region a significant part of the production fund is operated by electric submersible pumps, and the main complication in oil production is the formation of asphalt-resin-paraffin deposits. The authors proposed a technological justification for changing the diameter of the tubing string to reduce the intensity of organic deposits formation. This justification includes determining the change in the following parameters: friction pressure losses, energy consumption of oilfield equipment, oil flow rate and temperature distribution along the wellbore. Changing the last parameters has a significant impact on the intensity of paraffin deposits on the inner surface of the tubing. Evaluation calculations for the target well showed that a decrease in the diameter of the lifting string leads to an increase in the temperature of its inner surface, the flow rate in the lifting string, friction pressure losses and, accordingly, the energy consumption of oilfield equipment. For correct modeling of changes in the intensity of paraffin formation, laboratory studies were carried out on the WaxFlowLoop installation under various thermobaric and kinetic conditions. It has been shown that an increase in the flow rate and temperature in the lifting string can significantly reduce the rate of paraffin formation and, accordingly, increase the time interval between cleaning the well from organic deposits. An assessment of the inter-cleaning period of the well was carried out, and a clean-up operation for different diameters of the production string is supposed to be carried out when the same residual flow area is reached. As a result of the calculations, it was found that by reducing the diameter of the production string from the standard size from 73 to 42 mm it is possible to reduce the well cleanup period by 96.2%. At the same time, the increase in the cost of electricity for changing the operating mode of the downhole pumping equipment is insignificant.

References

1. Ilushin P., Vyatkin K., Kozlov A., Development of an approach for determining the effectiveness of inhibition of paraffin deposition on the wax flow loop laboratory installation, Inventions, 2021, V. 7, no. 1, https://doi.org/10.3390/inventions7010003

2. Bukreev V.G., Sipaylova N.Yu., Sipaylov V.A., Control strategy in accordance with economical criterion for electrotechnical installation of mechanized oil production (In Russ.), Izvestiya Tomskogo politekhnicheskogo universiteta. Inzhiniring georesursov = Bulletin of the Tomsk Polytechnic University. Geo Assets Engineering, 2017, V. 328, no. 3, pp. 75-84.

3. Jia A., Guo J., Key technologies and understandings on the construction of Smart Fields, Petroleum Exploration and Development, 2012, V. 39m, pp. 127–131, https://doi.org/10.1016/S1876-3804(12)60024-X

4. Ehsani S., Mehrotra A.K., Validating heat-transfer-based modeling approach for wax deposition from paraffinic mixtures: an analogy with ice deposition, Energy & Fuels, 2019, V. 33, no. 3, pp. 1859–1868, https://doi.org/10.1021/acs.energyfuels.8b03777

5. Mehrotra A.K. et al., A review of heat transfer mechanism for solid deposition from “waxy” or paraffinic mixtures, The Canadian Journal of Chemical Engineering, 2020, V. 98, no. 12, pp. 2463-2488, https://doi.org/10.1002/cjce.23829

6. Ilyushin P.Yu., Vyatkin K.A., Votinova A.O., Kozlov A.V., Methodology for evaluation of organic deposits thermal conduction using laboratory facility wax flow loop (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2021, V. 11, no. 6, pp. 622–629, https://doi.org/10.28999/2541-9595-2021-11-6-622-629

7. Li H., Zhang J., Viscosity prediction of non-Newtonian waxy crude heated at various temperatures, Petroleum science and technology, 2014, V. 32, no. 5, pp. 521–526, https://doi.org/0.1080/10916466.2011.596886

8. Safiulina A.G. et al., Modeling of paraffin wax deposition process in poorly extractable hydrocarbon stock, Chemistry and Technology of Fuels and Oils, 2018, V. 53, no. 6, pp. 897–904, https://doi.org/10.1007/s10553-018-0879-x

9. Krivoshchekov S.N., Vyatkin K.A., Kozlov A.V., Modeling of asphaltene-resin-wax deposits formation in a string of hollow rods during simultaneous separate operation of two oil reservoirs, Chemical and Petroleum Engineering, 2021, V. 57, pp. 213–219, https://doi.org/10.1007/s10556-021-00920-1

Petroleum industry rapid development requires prompt decision-making. The main focus is given to the industrial risks at offshore facilities, since this allows forecasting possible failures and avoiding explosions, fire or hydrocarbon spills. The offshore structures risk mitigation program contains technical, technological and organizational solutions, which allows converting the marine facilities to the recoverable systems and prolong their service life. As of today, Vietsovpetro operates the offshore facilities of fixed and wellhead platform type, the most of which have been built over 25 years ago and running out of their initially designed lifespans. Moreover, due to the long operation, many facilities had undergone changes of initial deck structure and equipment layout and have new unplanned wells. Besides man-induced operational factors it is required to consider the environment impact, which weakens the structures by corrosion and fouling leading to increased load from waves and currents. All these aspects lead to the reduced integrity of supporting frames and emergency stop risks of the platform or even collapsing. To ensure safety during operational and critical conditions, the support frames should undergo the reanalysis.

The article covers the stages of reanalysis for the support frames of the offshore fixed platform jacket. The calculation is made in DNV GL SESAM software complying API standards under operational and critical storm conditions. It is determined the period for removing the fouling from the support frames within the high-wave loads areas in order to reduce the cyclic impact to the structure, dismantling the non-required equipment and structures for off-loading the jackets. In case of need to install the unplanned additional wells at the offshore fixed platforms, authors propose the reduction of the existing tilting moment by decreasing the impact area of waves and currents.

References

1. Le Minh Tuan, Aleksan’yan A.A., Veliev M.M., Safe operation of the offshore oil and gas field facilities at Vietsovpetro JV (In Russ.), Problemy sbora, podgotovki i transporta nefti i nefteproduktov, 2011, no. 2 (84), pp. 116–123.

2. Veliev M.M., Bondarenko V.A., Zung L.V. et al., Sbor, podgotovka i transport produktsii skvazhin shel’fovykh mestorozhdeniy SP “V’etsovpetro” (Collection, preparation and transport of production wells of offshore fields of Vietsovpetro JV), St. Petersburg: Nedra Publ., 2020, 456 p.

3. API RP 2A-WSD. Recommended practice for planning, designing and constructing fixed offshore platforms – Working stress design, 22nd edition, 2014, 310 p.

4. AISC-ASD. Manual of steel construction – Allowable stress design, 9th Edition, 1989.

5. Local and technical conditions for 2007 “Gidrometeorologicheskie usloviya i iskhodnye raschetnye dannye dlya proektirovaniya ob”ektov obustroystva mestorozhdeniy “Belyy Tigr” i “Drakon” (Hydrometeorological conditions and initial design data for the design of the White Tiger and Dragon fields).

To ensure the safe operation of main oil pipelines, their periodic diagnostics by in-line inspection tool is carried out with the identification of a full range of various defects, determining their sizes, performing calculations for the strength and durability of pipe sections with defects, assigning the number and timing of repairs. The most dangerous are defects of the planar type of the factory weld and the base metal of the pipes, oriented in the longitudinal direction. The date of the next in-line inspection should be determined from the condition that none of the identified defects will lead to a failure during the inter-inspection period, or that the probability of such a failure should be sufficiently small. In this regard, it is important to assess the probability of failure of a pipeline section with in-plane defects identified by in-line inspection tool during the inter-inspection period. Failure is understood as the achievement of the dimensions of a planar defect during its fatigue growth of the limiting dimensions. The limiting dimensions of the defect are determined using a two-criteria fracture diagram according to the given design pressure for each defective section and the mechanical properties of the metal of pipes and welded joints.

This article presents a method for assessing the probability of destruction of a pipeline section with surface-type defects of a factory weld and the base metal of pipes, detected by an in-line inspection tool during scheduled in-line diagnostics. The technique was developed under the assumption that the initial depth and growth rate of defects are random variables. Thus, the parameter of cyclic crack resistance for pipe steels is also considered as a random variable. Empirical and calculated distributions of the error in measuring of the defect depth by in-line inspection tool are constructed. All defects are considered as surface semi-elliptical fatigue cracks with dimensions determined during in-line inspection. The fatigue crack growth kinetics is described by the Paris equation. The deterministic values are the length of the defect, the limiting depth of the defect at the design pressure, the reduced pressure cycling and operating pressure in the defective section, the pipe wall thickness. The results of the calculation according to the developed method of the dependence of the probability of failure on the value of the inter-inspection period for a section of the main oil pipeline containing 301 flat-type defects in the factory seam, oriented in the longitudinal direction. The length and depth of the defects were determined from the data of the in-line inspection tool.

References

1. Bushinskaya A.V., Otsenka veroyatnosti otkaza truboprovodnykh sistem s defektami korrozionnogo tipa po rezul'tatam ikh diagnostiki (Evaluation of the probability of failure of pipeline systems with corrosion-type defects based on the results of their diagnostics): thesis of candidate of technical science, Chelyabinsk, 2012.

2. Chirkov Yu.A., Bauer A.A., Shchepinov D.N., Kushnarenko E.V., Metodika otsenki veroyatnosti razrusheniya truboprovodov (Methodology for assessing the probability of destruction of pipelines), Proceedings of V International scientific conference “Prochnost' i razrushenie materialov i konstruktsiy” (Strength and destruction of materials and structures), March, 12–14, 2008, Orenburg: Publ. of OSU, 2008.

3. Witek M., Steel pipeline failure probability evaluation based on in-line inspection results (In Russ.), Pipeline Technology Journal, 2018, V. 3, pp. 16-21.

4. Bushinskaya A.V., Timashev S.A., Predictive maintenance of pipelines with different types of defects, Russian Journal of Construction Science and Technology, 2018, V. 4, no. 1, pp. 25-33, https://doi.org/10.15826/rjcst.2018.1.002

5. Matvienko Yu.G., Reznikov D.O., Kuz'min D.A., Potapov V.V., Assessment of the probability of the fatigue fracture of structural components subjected to deterministic and stochastic loading taking into account the scatter in the initial crack size (In Russ.), Zavodskaya laboratoriya. Diagnostika materialov, 2021, V. 87, no. 10, pp. 44–53, https://doi.org/10.26896/1028-6861-2021-87-10-44-53

6. Bubenik T., Harper W.V., Moreno P., Polasik St., Determining reassessment intervals from successive in-line inspections, Proceedings of the 2014, 10th International Pipeline Conference, September 29 – October 3, 2014, Calgary, https://doi.org/10.1115/IPC2014-33025

7. Semiga V., Dinovitzer A., Probabilistic fitness-for-service assessment of pipeline, Proceedings of the 2012 9th International Pipeline Conference, September, 24–28, 2012, Calgary, https://doi.org/10.1115/IPC2012-90422

8. Chan P.D., Webster D., Probabilistic assessment of ILI metal loss features, Proceedings of the 8th International Pipeline Conference, September 27 – October 1, 2010, Calgary, https://doi.org/10.1115/IPC2010-31298

9. Bushinskaya A.V., Timashev S.A., Predictive maintenance of pipelines with different types of defects (In Russ.), Neftegaz.ru, 2014, no. 5, рр. 28–35.

10. Timashev S.A., Bushinskaya A.V., Practical methodology of predictive maintenance for pipelines, Proceedings of the 8th International Pipeline Conference, September 27 – October 1, 2010, Calgary, https://doi.org/10.1115/IPC2010-31197

11. Matvienko Yu.G., Kuz'min D.A., Zatsarinnyy V.V. et al., Substantiation of probabilistic safety factors as a factor for optimizing the metal consumption of pipelines and the permissible operating pressure (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2021, no. 11(4), pp. 364–371, https://doi.org/ 10.28999/2541-9595-2021-11-4-364-371

12. CSA Z662:19. Oil and gas pipeline systems, CSA Group, 2019, 922 p.

13. Mekhanika katastrof. Opredelenie kharakteristik treshchinostoykosti konstruktsionnykh materialov. Metodicheskie rekomendatsii (Mechanics of catastrophes. Determination of crack resistance characteristics of structural materials. Guidelines), Part 2, Moscow: Publ. of FTsNTP PP “Bezopasnost'”, Assotsiatsiya KODAS, 2001, 254 p.

14. Pestrikov V.M., Morozov E.M., Mekhanika razrusheniya tverdykh tel (Fracture mechanics of solid bodies), St. Petersburg: Professiya Publ., 2002, 320 p.

15. API 579/ASME FFS-1. Fitness for service.

16. Sapunov V.T., Prochnost' povrezhdennykh truboprovodov. Tech' i razrushenie truboprovodov s treshchinami (Strength of damaged pipelines. Leakage and destruction of pipelines with cracks), Moscow: KomKniga Publ., 2005, 192 p.

17. Kapur K.C., Lamberson, L.R., Reliability in engineering design, New York: John Wiley&Sons, 1997.