The Precaspian depression is located within the southeastern margin of the East European Platform. This is one of the largest and deepest depressions of ancient platforms and one of the largest salt dome areas in the world. The article considers the problems associated with the reconstruction of the conditions of the unique Precaspian depression formation, peculiarities of applicability of geological and geophysical data for the analysis of different in age and depth parts of the geological section, provides a brief review of existing concepts of the formation of the depression. The dependence of formation and development of petroleum systems on the peculiarities of the considered concept is considered separately. All data for the analysis of hydrocarbon systems, as well as the results of any other studies of the Precaspian basin, are characterized by poor age and area distribution. In this regard, reconstructions of the conditions of the formation of the depression become of great importance, since they allow evaluation of the missing data, and therefore make forecasts more targeted. First of all, this relates to the restoration of sedimentation conditions, retrospective forecast of thermobaric conditions, etc. An important aspect of the study is the type of hydrocarbon systems. The authors consider drainless or autoclave systems, i.e. systems where hydrocarbons remain in situ - directly in oil and gas source rocks or in an adjacent reservoir without the possibility of long-distance migration. Deposits with such conditions could, for example, form in the Lower Permian alluvial fans in the central part of the depression. However, it is worth noting that deep-sea fans are found not only in the Permian, but also in the Carboniferous and Devonian complexes. Such conditions lead to a further stretching of the catagenesis scale, and also have a positive effect on the preservation of reservoirs, which, under conditions of the early arrival of hydrocarbons, become significantly less compacted as they sink. Thus, based on the considered concept of the formation of the Precaspian depression, the forecast for the oil and gas potential of the entire territory, including the most submerged Central Precaspian depression, and the entire Phanerozoic section is favorable.

References

1. 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, 262 p.

2. Pavlovskiy E.V., Zones of pericratonic subsidence - platform structures of the first order (In Russ.), Izvestiya Akademii nauk SSSR. Seriya geologicheskaya, 1959, no. 12, pp. 3–10.

3. Bogdanov A.A., Muratov M.V., Khain V.E., Ob osnovnykh strukturnykh elementakh zemnoy kory (About the main structural elements of the earth’s crust), Byulleten’ Moskovskogo obshchestva ispytateley prirody. Otdel geologicheskiy, 1963, V. 38, no. 3, pp. 3-32.

4. Burlin Yu.K., Yakovlev G.E., Galushkin Yu.I. Basseynovyy analiz (Basin analysis), Moscow: Publ. of MSU, 2007, 112 p.

5. Atlas litologo-paleogeograficheskikh, strukturnykh, palinspaticheskikh i geoekologicheskikh kart Tsentral’noy Evrazii (Atlas of lithological-paleogeographic, structural, palinspatic and geoecological maps of Central Eurasia), Almaty: Publ. of YuGGEO, 2002.

6. Zhuravlev V.S., Sravnitel’naya tektonika Pechorskoy, Prikaspiyskoy i Severomorskoy ekzogonal’nykh vpadin Evropeyskoy platformy (Comparative tectonics of the Pechora, Caspian and North Sea exogonal depressions of the European Platform), Moscow: Nauka Publ., 1972, pp. 408 p.

7. Izmalkova E.A., Khafizov S.F., Iskaziev K.O. et al., A new look at formation and the deep geological structure of the Pre-Caspian oil and gas basin based on a comprehensive analysis of geological and geophysical data (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2023, No. 5, pp. 14-20, DOI: https://doi.org/10.24887/0028-2448-2023-5-14-20

The oil and gas industry plays a key role in the economic development of the Republic of Kazakhstan, and strategic planning of prospecting and exploration of new fields also plays an important role in this process. The national oil and gas company KazMunayGas (KMG), represented by its subsidiary KMG-Barlau, is actively engaged in geological exploration of promising regional areas in the main oil and gas basins of the country. Research within the framework of geological exploration of subsoil is of a scientific and technical nature, and is aimed at poorly studied areas of promising regions. As a part of this research, KMG is conducting studies in five promising areas within the Aktobe (Mugodzhary block), West Kazakhstan (Berezovsky block), Mangistau regions (Zharkyn, Bolashak and North Ozen blocks). This project is carried out using modern technologies both when performing field seismic work and at the stage of processing and analyzing the obtained data in order to reduce uncertainties and geological risks. Most of the seismic work was completed in March 2024. Some areas are currently undergoing processing and interpretation of the new data acquired. The seismic work is expected to be completed by 2025. This article presents preliminary results as well as basic assumptions of the prospectivity of potential hydrocarbon deposits within the selected projects, with the total geological potential of the resource base estimated at approximately 3 billion tons of oil and gas equivalent.

References

1. Maksimov S.P., Shpil’man I. A., Bakhtiyarov R. B., Shpil’man S.I., The direction and geologic prospecting methods used to discover and explore gas fields on the northern flank of Precaspian depression (In Russ.), Geologiya nefti i gaza, 1983, no. 1, pp. 1-8.

2. 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.

3. Bakirov K Kh., Chimbulatov M.A., Yakovlev A.V., Valeev D.Z., Tektonika i neftegazonosnost’ Aktyubinskogo Priural’ya (Tectonics and oil and gas potential of the Aktobe Cis-Urals), Moscow: Nedra Publ., 1972, 199 p.

4. 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.

5. 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.

6. Kunitsyna I. V., Nikishin A.M., Malyshev N.A. et al., Tectonostratigraphy and history of geological development of North Caspian fold-thrust zone (In Russ.), Vestnik Moskovskogo universiteta. Seriya 4. Geologiya = Moscow University Bulletin Series 4 Geology, 2022, no. 5, pp. 35–46, DOI: http://doi.org/10.33623/0579-9406-2022-5-35-46

7. Popkov V.I., Popkov I.V., Pre-upper permian deposits of the buzachi peninsula and the prospects for their oil and gas potential (In Russ.), Vestnik Akademii nauk Respubliki Bashkortostan, 2021, no. 3(103), pp. 5-15, DOI: http://doi.org/10.24412/1728-5283-2021-3-5-15

The study of the Precaspian basin being the key oil and gas bearing basin in Kazakhstan remains extremely insufficient, despite the discovery of supergiant oil and gas fields. The main problem of its study is related to the large thickness of the sedimentary mantle, a significant part of which is assessed as oil-prospective due to the peculiarities of its structure. All discoveries made in the pre-salt complex relate to the marginal parts of the depression or the so-called flank zones. Deeper horizons in the central part remain virtually unexplored. The Eurasia project was initiated about 20 years ago to address this problem. It is divided into three phases. Phase 1, which involves reinterpretation of the accumulated geological and geophysical information, was completed in 2022. The main goal of phase 1 was to identify the most promising areas of deep-lying objects and develop programs for further geological exploration for phase 2. The geological exploration planned in phase 2 must be carried out using the most advanced, efficient, knowledge-intensive and innovative exploration technologies; its results must provide reliable data on the deep geological structure of the study area to depths of 20–25 km. Phase 3 is expected to involve the drilling of an ultradeep (10–15 km) parametric well. The results of phase 3 of the Eurasia project will make it possible to clarify the deep hydrocarbon potential of the Caspian basin. The data obtained can be used when planning similar work in other oil and gas basins. New methods of geophysical exploration and drilling of ultradeep wells will become the basis for new high-tech technologies and techniques. The criteria for selecting the location of the borehole, discussed in this article, are of critical importance.

References

1. Volozh Yu.A., Abukova L.A., Antipov M.P. et al., Utoclave type of the hydrocarbon systems in the Caspian oil and gas bearing province (Russia): Conditions of formation at great depth (In Russ.), Geotektonika, 2022, no. 6, pp. 1–19, DOI: https://doi.org/10.31857/S0016853X22060078

2. Volozh Yu.A., Antipov M.P., Kuandykov B.M. et al., Kaspiyskiy region: problema poiska uglevodorodov na bol’shikh glubinakh, vozmozhnye puti ee resheniya (Caspian region: the problem of searching for hydrocarbons at great depths, possible ways to solve it), Proceedings of ONGK, 2024, V. 4, pp. 20–33.

The article considers the results of 3D basin modeling of the subsalt deposits in Kazakhstan part of the Precaspian basin. Special attention is paid to the kinetic spectrum of kerogen degradation and its effect on the generation time of hydrocarbon fluids in oil and gas source rocks. According to the results of fluid dynamic modeling, the Devonian source rocks began to generate hydrocarbon fluids in the Prekungurian geological period, about 286,8 million years ago. At the turn of the Permian and Triassic time (251,9 million years ago), the degree of transformation of organic matter reached 50 % everywhere. The realization of the potential of the Carboniferous and Permian source rocks began after the accumulation of the Kungurian salt deposits. At the turn of the Permian and Triassic geological time (251,9 million years ago), the main generation center was formed in the Central Caspian depression, local generation occured in the south of the simulated region. Currently, the degree of potential realization for all oil and gas source rocks has a similar distribution. There are two large centeres of generation: in the central part of the Caspian basin and in the south of the simulated area. Laboratory studies of core samples of the Upper Devonian and Lower Permian ages show the presence of deposits rich in organic matter in these age ranges. The obtained kinetic spectrum for these rocks showed a relatively early generation of hydrocarbon fluids from the oil and gas source rocks. Thus, the peak generation for the Lower Permian deposits is observed in the temperature range 125–140 °C, for the Upper Devonian – 130–160 °C. A comparison of the calculation results of basic scenario 1 with standard kinetic spectrum from the TemisFlow™ library and scenario 2 with destruction schemes determined during laboratory studies showed differences in the transformation index of about 2–10 %. It is worth noting that the different reaction rates had the greatest impact on Devonian sediments in the Prekungurian stage of development of the Precaspian oil and gas basin in local areas of the side parts of the depression.

References

1. 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

2. Behar F., Vandenbroucke M., Tang Y. et al., Thermal cracking of kerogen in open and closed systems: Determination of kinetic parameters and stoichiometric coefficients for oil and gas generation, Organic Geochemistry, 1997, V. 26, no. 5–6, pp. 321–339, DOI: https://doi.org/10.1016/S0146-6380(97)00014-4

3. Vandenbroucke M., Behar F., Rudkiewicz J.L., Kinetic modelling of petroleum formation and cracking: Implications from the high pressure/high temperature Elgin Field (UK, North Sea), Organic Geochemistry, 1999, V. 30, no. 9, pp. 1105–1125, DOI: https://doi.org/10.1016/S0146-6380(99)00089-3

4. Burnham A.K., Global chemical kinetics of fossil fuels, Springer International Publishing, 2017, 315 p., DOI: https://doi.org/10.1007/978-3-319-49634-4

5. Peters K.E., Burnham A.K., Walters C.C., Petroleum generation kinetics: Single versus multiple heating ramp open-system pyrolysis, AAPG Bulletin, 2015, V. 99, no. 4, pp. 591–616, DOI: http://doi.org/10.1306/01141615146

The article presents a study of 17 crude oil samples and 6 source rock samples using geochemical methods from the Mesopotamian Basin (North-East Syria) and North-East Palmyrides (Central Syria), in order to identify the geochemical correlation between them.The results of the study allowed the identification of two groups of oils, which were labeled as A and B. The distinguishing feature of these oils is their different origin, which was established based on biomarkers. Oils of these groups are generated by different types of source rocks of different ages. Group A oils were formed in relatively young marine clastic source rocks found in Middle Triassic, Middle Jurassic and Upper Cretaceous reservoirs in the North-Eastern Palmyrides area. The geochemical characteristics of these oils are similar to extracts from the Lower Triassic Amanus Shale Formation. Group B oils are present in Middle Triassic, Middle Jurassic and Upper Cretaceous reservoirs in the Mesopotamian foredeep. The geochemical characteristics of these oils are similar to extracts from Middle Triassic dolomites of the Curra Chine and Upper Cretaceous Shiranish formations. This study provides information about the origin and migration of oil in these regions, which may have important practical implications for the exploration and development of oil fields in Syria. Determining the sources of oil and the characteristics of source rocks allows more efficient and accurate production planning and optimization of field development processes, which, in turn, can contribute to increased production and economic development of the region.

References

1. Brew G., Barazangi M., Al-Maleah K., Sawaf T., Tectonic and geologic evolution of Syria, GeoArabia, 2001, no. 6, pp. 573-616,

DOI: http://doi.org/10.2113/geoarabia0604573a

2. Litak R.K., Barazangi M., Brew G., Sawaf T., Structure and evolution of the petroliferous Euphrates graben system, Southern Syria, AAPG Bull., 1998, no. 82, pp. 1173–1190, DOI: http://doi.org/10.1306/1d9bca2f-172d-11d7-8645000102c1865d

3. Barazangi M., Saber D., Chaimov J., Tectonic evolution of the northern Arabian plate in Western Syria, In: Recent Evolution and Seismicity of the Mediterranean Region: edited by Boschi E. et al., Kluwer Academic Publishers, 1993, pp. 117-140.

4. Alyaseen M.Kh., Methods for predictive assessment of oil and gas content in the fields of the Euphrates graben (In Russ.), Neftegazovoe delo, 2021, no. 2, pp. 17–26, DOI: https://doi.org/10.17122/ngdelo-2021-2-17-26

5. Moldovan J.M., Seifert W.K., Gallegos E.J., Relationship between petroleum composition and depositional environment of petroleum source rocks, AAPG Bull., 1985, no. 69, pp. 1255–1268, DOI: https://doi.org/10.1306/AD462BC8-16F7-11D7-8645000102C1865D

6. Zumberge J.E., Sutton C., Martin S.J., Worden R.D., Determining oil generation kinetic parameters by using a fused-quartz pyrolysis system, Energy and Fuels, 1988, no. 2, pp. 264–266, DOI: http://doi.org/10.1021/ef00009a006

7. Peters K.E., Moldovan J.M., The biomarker guide interpreting molecular fossils in petroleum and ancient sediments, Prentice Hall, 1993, 363 p.

8. Fuex A.N., The use of stable carbon isotopes in hydrocarbon, Journal of Geochemical Exploration, 1977, no. 7, pp. 155–188, DOI: https://doi.org/10.1016/0375-6742(77)90080-2

9. Safer Z., Stable carbon isotope compositions of crude oils: Application to source depositional environments and petroleum alternation, AAPG Bull., 1984, no. 68, pp. 31–49, DOI: https://doi.org/10.1306/AD460963-16F7-11D7-8645000102C1865D

The article considers general information about the structure of the Western Precaucasus and adjacent territories of the Greater Caucasus orogen. The modern mountain structure of the Greater Caucasus, formed on the southern periphery of the Epigercine Scythian plate in the Late Alpine epoch of tectogenesis, is an example of a typical epiplatform orogen. The modern regions of the Greater Caucasus and western Precaucasia in the Mesozoic and Cenozoic up to the end of the Pliocene were part of the marginal continental part of the Parathetis basin. By the end of the Neogene, multi-kilometer Upper Mesozoic-Cenozoic strata of the plate cover was formed in the Greater Caucasus and Western Precaucasus. Probably, the Greater Caucasus orogen began to rise no earlier than the Pliocene, and possibly later – in the Quaternary, no earlier than 2,6–2 million years ago. Accordingly, over a short period of time (2,6–2 million years ago), the orogen experienced rapid uplift. The overlying strata of the plate cover underwent rapid denudation - hypergene and tectonic erosion, as a result, in the axial zone of the orogen, complexes of the granite-metamorphic basement of the Greater Caucasus were exposed, the erosion products of which are recorded in Quaternary molasse. The products of destruction of the orogen of the Greater Caucasus in the bends of the Western Precaucasia form low-power strata of orogenic molasses of Quaternary age. These formations comprise extremely small volumes, which are not comparable with the amplitudes of the uplift of the Greater Caucasus and the estimated capacities (many kilometers) of the strata that overlapped the complex of the Paleozoic base of the Greater Caucasus. The formation of the modern orogen of the Greater Caucasus and coarse Molasses deposits associated with the destruction of this uplift began no earlier than the Pliocene, probably in the Eopleistocene. The high growth rates of the Greater Caucasus orogen and the small volumes of its destruction products accumulated in the Western Precaucasian trough collectively represent a contradictory phenomenon that cannot be explained solely by the factor of erosion of the Greater Caucasus.

References

1. Bol’shoy Kavkaz v al’piyskuyu epokhu (Greater Caucasus in the Alpine era): edited by Leonov Yu.G., Moscow: GEOS Publ., 2007, 368 p.

2. Milanovskiy E.E., Khayn V.E., Geologicheskoe stroenie Kavkaza (Geological structure of the Caucasus), Moscow: Publ. of MSU, 1963, 357 p.

3. Kopp M.L., Shcherba I.G., Caucasian basin in the Paleogene (In Russ.), Geotektonika, 1998, no. 2, pp. 29–50.

4. Leonov M.G., Dikiy flish Al’piyskoy oblasti (Wild flysch of the Alpine region), Moscow: Nauka Publ., 1975, 149 p.

5. Stolyarov A.S., Paleogeography of Ciscaucasia, Volga-Don and Southern Mangyshlak in the Late Eocene and Early Oligocene (In Russ.), Byulleten’ MOIP. Otdel geologicheskiy = Bulletin of Moscow Society of Naturalists. Geological Series, 1991, V. 6, no. 4, pp. 64–80.

6. Sharafutdinov V.F., Geologicheskoe stroenie i zakonomernosti razvitiya maykopskikh otlozheniy severo-vostochnogo Kavkaza v svyazi s neftegazonosnost’yu (Geological structure and patterns of development of Maikop deposits of the northeastern Caucasus in connection with oil and gas potential): thesis of doctor geological and mineralogical science, Moscow, 2003.

7. Vincent S.J., Morton A.C., Carter A. et al., Oligocene uplift of the Western Greater Caucasus; an effect of initial Arabia-Eurasia collision, Terra Nova, 2007, no. 19, pp. 160-166.

8. Avdeev B., Niemi N.A., Rapid Pliocene exhumation of the central Greater Caucasus constrained by low-temperature thermochronometry (In Russ.), Tectonics, 2011,

V. 30, pp. 1–16, DOI: http://doi.org/10.1029/2010TC002808

9. Pushcharovskiy Yu.M., Kraevye progiby, ikh tektonicheskoe stroenie i razvitie (Marginal troughs, their tectonic structure and development), Proceedings of Geological Institute of the USSR Academy of Sciences, 1959, V. 28, 155 p.

10. Muratov M.V., Types of depressions in the sedimentary cover of ancient platforms (In Russ.), Byulleten’ MOIP. Otdel geologicheskiy = Bulletin of Moscow Society of Naturalists. Geological Series, 1972, V. 47, no. 5, pp. 61–71.

11. Popov S.V., Antipov M.P., Zastrozhnov A.S. et al., Sea level fluctuations on the northern shelf of the Eastern Paratethys in the Oligocene – Neogene (In Russ.), Stratigrafiya. Geologicheskaya korrelyatsiya, 2010, V. 18, no. 2, pp. 99–124.

12. Kuznetsov N.B., Romanyuk T.V., Dantsova K.I. et al., On the tectonic nature of the Western Kuban trough (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2023, no. 9, pp. 78–84, DOI: http://doi.org/10.24887/0028-2448-2023-9-78-84

13. Kuznetsov N.B., Romanyuk T.V., Shatsillo A.V. et al., Vozrasty detritovogo tsirkona iz peskov belorechenskoy svity (zapadnoe Predkavkaz’e): predvaritel’nye vyvody o ee vozraste i o vremeni nachala obrazovaniya noveyshego orogena Bol’shogo Kavkaza (Ages of detrital zircon from sands of the Belorechenskaya Formation (western Ciscaucasia): preliminary conclusions about its age and the time of the beginning of the formation of the newest orogen of the Greater Caucasus), Proceedings of All-Russian Conference with international participation “LV Tektonicheskoe soveshchanie. Tektonika i geodinamika Zemnoy kory i mantii: fundamental’nye problemy-2024” (LV Tectonic meeting. Tectonics and geodynamics of the Earth’s crust and mantle: fundamental problems-2024), 2024, V. 1, pp. 244–249.

14. Nikishin A.M., Ershov A.V., Nikishin V.A., Geological history of Western Caucasus and adjacent foredeeps based on analysis of the regional balanced section, Dokl. Earth Sci., 2010, V. 430, no. 2, pp. 155–157, DOI: https://doi.org/10.1134/S1028334X10020017

15. Gamkrelidze I., Shengelia D., Chichinadze G. et al., U–Pb LA-ICP-MS dating of zoned zircons from the Greater Caucasus pre-Alpine crystalline basement: Evidence for Cadomian to Late Variscan evolution, Geologica Carpathica, 2020, V. 71, no. 3, pp. 249‒263, DOI: http://doi.org/10.31577/GeolCarp.71.3.4

16. Korsakov C.G., Semenukha I.N., Beluzhenko E.V. et al., Gosudarstvennaya geologicheskaya karta Rossiyskoy Federatsii. Masshtab 1:200 000 (State geological map of the Russian Federation. Scale 1:200 000), Seriya Kavkazskaya (Caucasian Series). List L – 37 – XXXV. (Maykop). Poyasnitel’naya zapiska (Sheet L – 37 – XXXV. (Maykop). Explanatory note), St. Petersburg: Publ. of VSEGEI, 2004, 301 p.

17. Somin M., Pre-Jurassic basement of the Greater Caucasus: brief overview, Turkish J of Earth Sci., 2011, V. 20, pp. 545–610, DOI: https://doi.org/10.3906/yer-1008-6

18. Kolodyazhnyy S.Yu., Makhinya E.I., Shalaeva E.A., Dantsova K.I., Osobennosti pozdneal’piyskoy tektoniki Adygeyskogo sektora Bol’shogo Kavkaza (Features of the Late Alpine tectonics of the Adyghe sector of the Greater Caucasus), Proceedings of All-Russian Conference with international participation “LV Tektonicheskoe soveshchanie. Tektonika i geodinamika Zemnoy kory i mantii: fundamental’nye problemy-2024” (LV Tectonic meeting. Tectonics and geodynamics of the Earth’s crust and mantle: fundamental problems-2024), 2024, V. 1, pp. 202–206.

19. Beluzhenko E.V., Volkodav I.G., Derkacheva M.G. et al., Oligotsenovye i neogenovye otlozheniya doliny reki Beloy (Adygeya) (Oligocene and Neogene deposits of the Belaya River valley (Adygea)), Maykop: Publ. of ASU, 2007, 110 p.

20. Kuznetsov N.B., Romanyuk T.V., Dantsova K.I. et al., Characteristics of sedimentary strata of the Indolo-Kuban trough as indicated by the results of U–Pb isotopic dating of detrital zircons (In Russ.), Nedra Povolzh’ya i Prikaspiya, 2024, no. 1, pp. 4–15, DOI: http://doi.org/10.24412/1997-8316-2024-113-4-15

With the advent of the first satellite images of the Caspian Sea and the adjacent Turan plate, they became the object of studying the possibilities of using space imagery for geological purposes. The article presents the results of decryption using the WinLessa software package. The comparison of the lineament decoding scheme correlates well with modern tectonic schemes, for example, with the structural-tectonic map of the roof of the consolidated crust of the studied territory. The decryption scheme highlights all the main faults shown on the map of the consolidated crust, such as the North Karatau and Central Usyurt faults, and the Pachelma Rift. In addition, the southeastern extension of the Pachelma rift to the territory of the Caspian Sea and further to the Turan plate is highlighted, as well as the fault along which the valley in the lower reaches of the Volga River on the Volgograd-Astrakhan segment is developed. Elementary strokes are highlighted on different scales, which correspond to linear elements of the landscape of 715 km length and have similar characteristics on the same areas and differ in different ones. This indicates their reproducibility and informative value. The predominant orientation of small lineaments forms cluster sites in the form of blocks with a diameter of about 100 km. The highlighted rays of the rose diagrams correspond to the directions of the planetary fracturing (regmatic network). Global lineaments and their bundles divide the entire territory into separate blocks. When compared with the map of the consolidated crust, this is confirmed. At the same time, the well-defined lineaments in the images may be secondary and may not be the boundaries of large tectonic blocks, whereas the boundaries of large blocks are not so clearly expressed. The blocks that stand out in small strokes fit into the specified larger ones, like puzzle elements.

References

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2. 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.

3. Amurskiy G.I., Bondareva M.S., Kats Ya.G. et al., Izuchenie tektoniki neftegazonosnykh oblastey s ispol’zovaniem kosmicheskikh snimkov (Studying the tectonics of oil and gas bearing areas using satellite images), Moscow: Nedra Publ., 1985, 143 p.

4. Bush V.A., Analiz kosmogeologicheskoy karty SSSR masshtaba 1:2 500 000 (Analysis of the cosmogeological map of the USSR at a scale of 1:2,500,000), In: Kosmogeologiya SSSR (Cosmogeology of the USSR): edited by Bryukhanov V.N., Mezhelovskiy N.V., Moscow: Nedra Publ., 1987.

5. Shul’ts S.S., Planetarnaya treshchinovatost’ (Planetary fracturing), Leningrad: Publ. of LSU, 1973, 90 p.

6. Kats Ya.G., Poletaev A.I., Rumyantseva E.F., Osnovy lineamentnoy tektoniki (Fundamentals of Lineament Tectonics), Moscow: Nedra Publ., 1986, 140 p.

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8. Gavrilov V.P., Gulyaev N.B., Gibshman N.B. et al., Geologiya i perspektivy neftegazonosnosti verkhnepaleozoyskikh otlozheniy Ustyurtskogo regiona (Geology and prospects for oil and gas potential of Upper Paleozoic deposits of the Ustyurt region), Moscow: Nedra Publ., 2014, 247 p.

9. Zlatopol’skiy A. A., Using LESSA technology to obtain territory orientation characteristics. Methodology and testing with digital elevation model for the pre-Baikal region (In Russ.), Sovremennye problemy distantsionnogo zondirovaniya Zemli iz kosmosa, 2020, no. 4, pp. 98–110.

10. 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, 262 p.

The article presents the results of seismostratigraphic section analysis of the southern part of the Western Precaucasus basin. It showed a widespread development of detachments in the area under study. As a rule, detachments are confined to the boundaries of strata with different rheological behavior and zones with considerably tilted layers at areas adjacent to the Caucasus orogen or, less often, to buried uplifts. Various structures associated with sliding processes along detachments have been identified: asymmetric folds and small overhangs, domino structures and splintering zones. Numerous buried ledges and associated clinoforms have been deciphered on seismic sections of the eastern part of the Western Kuban trough, which can be considered as paleodeltas – accumulative structures of detrital material, transported from north to south into the area of wide shelf of the southern margin of the East European Platform. It is suggested that one of the forms of manifestation of the Greater Caucasus latest orogeny is the tectonic exhumation of the lower layers of the sedimentary cover and complexes of the granite-metamorphic base of the orogen due to the tectono-gravitational collapse of the mountain structure. The detachments are associated with asymmetric folds and thrusts, splintering zones, decompression and compression ramps, which under certain conditions can be traps for hydrocarbons.

References

1. Nikishin A.M., Ershov A.V., Nikishin V.A., Geological history of the Western Caucasus and associated foredeeps based on the analysis of a regional balanced section (In Russ.), Doklady RAN. Nauki o Zemle = Doklady Earth Sciences, 2010, V. 430, no. 4, pp. 515–517.

2. Klavdieva N.V., Tektonicheskoe pogruzhenie kavkazskikh kraevykh progibov v kaynozoe (Tectonic subsidence of the Caucasian marginal troughs in the Cenozoic): thesis of candidate of geological and mineralogical science, Moscow: MSU, 2007.

3. E Beluzhenko E.V., Volkodav I.G., Derkacheva M.G. et al., Oligotsenovye i neogenovye otlozheniya doliny reki Beloy (Adygeya) (Oligocene and Neogene deposits of the Belaya River valley (Adygea)), Maykop: Publ. of ASU, 2007, 110 p.

4. Korsakov C.G., Semenukha I.N., Beluzhenko E.V. et al., Gosudarstvennaya geologicheskaya karta Rossiyskoy Federatsii. Masshtab 1:200 000 (State geological map of the Russian Federation. Scale 1:200 000), Seriya Kavkazskaya (Caucasian Series). List L – 37 – XXXV. (Maykop). Poyasnitel’naya zapiska (Sheet L – 37 – XXXV. (Maykop). Explanatory note), St. Petersburg: Publ. of VSEGEI, 2004, 301 p.

5. Mollaev Z.Kh., Dotsenko V.V., Bachaeva T.Kh., Kontseptsii formirovaniya Zapadno-Kubanskogo kraevogo progiba (Concepts of the formation of the Western Kuban foredeep), Collective monograph based on the materials of the X All-Russian Scientific and Technical Conference “Sovremennye problemy geologii, geofiziki i geoekologii Severnogo Kavkaza” (Modern problems of geology, geophysics and geoecology of the North Caucasus), Groznyy, 14–16 October 2020, Part 1, Groznyy: Format Publ., 2020, pp. 179-186.

6. Popkov V.I., Bondarenko N.A., Tektonika orogennykh sooruzheniy Severo-Zapadnogo Kavkaza (Tectonics of orogenic structures of the Northwestern Caucasus), Materials of the XLI Tectonic Meeting “Obshchie i regional’nye problemy tektoniki i geodinamiki” (General and regional problems of tectonics and geodynamics), Part 2, Moscow: GEOS Publ., 2008, pp. 125–130.

7. Shempelev A.G., Prutskiy N.I., Fel’dman I.S., Kukhmazov S.U., Geologo-geofizicheskaya model’ po profilyu Tuapse-Armavir (Geological and geophysical model for the Tuapse-Armavir profile), Materials of the XXXIV Tectonic Meeting ”Tektonika neogeya: obshchie i regional’nye aspekty” (Neogean tectonics: general and regional aspects), Part 2, 2001, Moscow, GEOS Publ., 2001, pp. 316-320.

8. Van Baak C.G.C., Krijgsman W., Grothe A. et al., Paratethys response to the Messinian salinity crisis, Earth-Science Reviews, 2017, V. 172, pp. 193-223, DOI: http://doi.org/10.1016/j.earscirev.2017.07.015

9. Palcu D.V., Lazarev S., Krijgsman W. et al., Late Miocene Megalake regressions in Eurasia, Scientific Reports, 2021, V. 11, no. 1, DOI: http://doi.org/10.1038/s41598-021-91001-z

10. Milanovskiy E.E., Noveyshaya tektonika Kavkaza (Recent tectonics of the Caucasus), Moscow: Nedra Publ., 1968, 482 p.

11. Kuznetsov N.B., Romanyuk T.V., Dantsova K.I. et al., On the tectonic nature of the Western Kuban trough (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2023,

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

12. Kolodyazhnyy S.Yu., Makhinya E.I., Shalaeva E.A., Dantsova K.I., Osobennosti pozdneal’piyskoy tektoniki Adygeyskogo sektora Bol’shogo Kavkaza (Features of the Late Alpine tectonics of the Adyghe sector of the Greater Caucasus), Proceedings of All-Russian Conference with international participation “LV Tektonicheskoe soveshchanie. Tektonika i geodinamika Zemnoy kory i mantii: fundamental’nye problemy-2024” (LV Tectonic meeting. Tectonics and geodynamics of the Earth’s crust and mantle: fundamental problems-2024), 2024, V. 1, pp. 202–206.

13. Khain V.E., Tektonika kontinentov i okeanov (god 2000) (Tectonics of continents and oceans (year 2000)), Moscow: Nauchnyy mir Publ., 2001, 606 p.

14. Pfiffner O.A., Thick-skinned and thin-skinned tectonics: A global perspective, Geosciences, 2017, V. 3, no. 7, DOI: http://doi.org/10.3390/geosciences7030071

Some issues of the geological development and structure of the productive intervals of the section after the exploration work in the south-east of the South Tatar arch and the adjacent part of the Aktanysh-Chishmin depression have not been fully resolved. For example, the conditions of formation and the nature of the distribution of sandy-siltstone reservoir rocks in the kosvinsk-bobrikovsky deposits of the lower carboniferous terrigenous strata have not been fully clarified. At the same time, the reserves of most oil fields in the Paleozoic sedimentary cover of the designated territory have been significantly depleted during long-term production and therefore new sources of replenishment are required. Based on the study of geological and geophysical data, it was revealed that the accumulation of terrigenous rocks of the kosvinsk-bobrikovsky time occurred in the conditions of an alluvial delta extending in a southeastern direction into the shallow shelf area. In the well section, these deposits can be represented by distributive delta channels, estuarine bars of the delta front and sands of floodplain spills. Siltstone-sandy rocks of the delta channels and the proximal part of the bars are characterized by the best porosity and permeability properties, while sediments of floodplains and the distal part of the bars have lower values of such properties. During the detailed analysis, the paths of transfer of detrital material were mapped and the formed facies were shown on a detailed map of the facies zoning of the eastern part of the South Tatar arch at the end of bobrikovsky time. This map was compiled for the first time by the authors and, on its basis, the association of discovered fields and oil deposits with certain facies is compared and a forecast is given for the discovery of new oil deposits in the areas of intersection of delta channels, estuarine bars with slopes and arches of positive local structures.

References

1. Sedimentary environments: processes, facies and stratigraphy: edited by Reading H.G., Blackwell Publishing Limited, Second edition, 1986.

2. Valeeva I.F., Anisimov G.A., Anisimova L.Z., Geological aspects of oil and gas potential in the Upper Devonian and Lower Carboniferous sediments of Aktanysh-Chishminsky deflection of Kamsko-Kinelsky system of deflections (In Russ.), Georesursy, 2015, V. 2, no. 3(62), pp. 37–42.

3. Masagutov R.Kh., Tyurikhin A.M., Nasser Kh., Litologo-fatsial’naya kharakteristika radaevsko-bobrikovskikh otlozheniy osevoy zony Aktanysh-Chishminskogo progiba (na primere Ilishevskogo mestorozhdeniya) (Lithological-facial characteristics of the Radaevsky-Bobrikovsky deposits of the axial zone of the Aktanysh-Chishminsky trough (using the example of the Ilishevsky field)), Proceedings of RN-BashNIPIneft’ LLC, 2001, V. 108, pp. 44–52.

4. Masagutov R.Kh., Tektonicheskoe stroenie Bashkiro-Tatarskogo Pribel’ya (Tectonic structure of the Bashkir-Tatar region), Proceedings of RN-BashNIPIneft’ LLC, 2000, V. 100, pp. 44–56.

5. Krasnevskiy Yu.S., Lozin E.V., A new type of oil deposits: annular, encircling reef body (In Russ.), Oil&Gas Journal Russia, 2015, no. 1–2, pp. 38–42.

6. Komilov D.U., Maleev R.I., Masagutov R.Kh., Tomilin V.E., Late Tula delta geology and hydrocarbons occurrences in the Upper Kama depression and adjacent area

(In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 12, pp. 86–90, DOI: https://doi.org/10.24887/0028-2448-2019-12-86-90

7. Komilov D.U., Geologiya i perspektivy neftenosnosti verkhnetul’sko-mikhaylovskikh otlozheniy platformennogo Bashkortostana (Geology and oil-bearing prospects of the Verkhnetula-Mikhailovsky deposits of platform Bashkortostan): thesis of candidate of geological and mineralogical science, Ufa, 2022.

Vietsovpetro JV conducts exploration and development of hydrocarbon fields on the continental shelf of Vietnam. The following fields were put into development at block 09-1: White Tiger, Dragon, White Bear, White Hare and Southern Dragon-Sea Turtle. During production a detailed study of the geological structure of productive rocks and deposits is carried out and a large amount of data has been obtained in productive deposits which characterizes the properties of reservoir and their distribution in rocks. The article discusses methods for studying the heterogeneity of reservoir rocks properties of productive deposits of the Lower Miocene deposits located on block 09-1, in the Vietnamese offshore. Based on the sediments, 8 productive units and 48 productive layers were identified. Their distribution over the area of the block and the section of deposits was studied. The average values of the distribution of porosity and oil saturation, characterizing geological heterogeneity, were determined and analyzed using statistical methods. Algorithms for the distribution of calculation parameters for the probabilistic-stochastic volumetric method of for calculating oil and gas reserves are proposed. The Monte Carlo method was used to quantify the parameters of deposits. According to the results of reservoir properties study at the White Tiger and Dragon fields during the recalculation of reserves in 2023–2024 years new productive deposits were identified that had not previously been identified during the study of the geological structure. The results of reserve volumetric recalculation were approved and tested during the development of deposits. The obtained data from studying the heterogeneity of reservoir properties and the geological structure of the White Tiger and Dragon fields are of practical interest when using the results of work in similar geological conditions in poorly studied areas and marginal deposits of the continental shelf of Vietnam. According to geological survey data, development and additional study of existing fields of block 09-1, using the example of productive deposits of the Lower Miocene, characteristics of the distribution of porosity and oil saturation of were obtained. Methods for assessing reservoir properties and volumetric reserves, prospects and marginal hydrocarbon plays of Vietnam continental shelf are considered. Conclusions are drawn about the application of methods for studying physical properties for similar conditions. Using this method, reserves of the White Tiger and Dragon fields were recalculated in 2023–2024 and approved in Vietnam.

References

1. Pryzhok “Belogo Tigra” dlinoyu v 35 let...: Geologicheskoe stroenie i neftegazonosnost’ shel’fovykh neftyanykh mestorozhdeniy SP “V’etsovpetro” (Leap of the «White Tiger» 35 years long…: Geological structure and oil and gas potential of offshore oil fields of Vietsovpetro JV): edited by Ty Tkhan’ Ngia, Veliev M.M., St. Petersburg: Nedra Publ., 2016, 524 p.

2. Ryumkin A.G., Lebedeva E.T., Ryumkin D.A., Prognoz rasprostraneniya marginal’nykh zalezhey na bloke 09-1 po geologo-geofizicheskim dannym mestorozhdeniya “Belyy Tigr” (Forecast of distribution of marginal deposits in block 09-1 based on geological and geophysical data of the White Tiger field), Collected papers “Innovatsionnye tekhnologii v neftegazovoy otrasli. Problemy ustoychivogo razvitiya” (Innovative technologies in the oil and gas industry. Problems of sustainable development), Stavropol, 2020, pp. 137–143.

3. Gabrielyants G.A., Poroskun V.I., Sorokin Yu.V., Metodika poiskov i razvedki zalezhey nefti i gaza (The method of prospecting and exploration of oil and gas deposits), Moscow: Nedra Publ., 1985, 304 p.

4. Ivanov A.N., Ryumkin A.G., Kholodilov V.Yu. et al., Geological aspects of Vietsovpetro JV oilfields (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 6,

pp. 18–21, DOI: https://doi.org/10.24887/0028-2448-2019-6-18-21

5. Ivanov A.N., Ryumkin A.G., Fedoseev M.A. et al., Using of stochastic methods for evaluation of hydrocarbon accumulation in terrigenous deposits

on JV Vietsovpetro’s oil fields (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2018, no. 8, pp. 6–9, DOI: https://doi.org/10.24887/0028-2448-2018-8-6-9

6. Feller W., An introduction to probability theory and its applications, Vol. 1, Wiley, 1957, 704 p.

7. Dubrule O., Geostatistic in petroleum geology, AAPG Continuing Education Course Note Series no. 38, AAPG, Tulsa, Oklahoma, U.S.A., 1998.

Most of the identified hydrocarbon deposits in Russia are at a late stage of development. For further effective study of sediments in various territories of the oil and gas regions of Russia, it is necessary to improve approaches and techniques for studying their areal structure, primarily the geological objects that make up the section. At the present stage, such studies are carried out using seismic research. In the old oil and gas producing regions of Russia, the undetected part of the resources is often concentrated in small-sized anticlinal and non-anticlinal objects, which are poorly detected in the seismic field. When prospecting for low-amplitude traps, additional difficulties may be caused by the strong variability of the upper part of the section, which introduces uncertainties in the degree of reliability of constructing structural plans based on seismic data. The accuracy of constructing the structural surfaces of the reflecting horizon when interpreting the results of seismic studies is comparable to the amplitude of the uplift. The purpose of this work is to identify and map zones and areas of development of geological objects with anomalous properties in the upper part of the section of the Cenozoic-Paleozoic sedimentary mantle for subsequent consideration of their influence on the results of seismic exploration using the areas located within the platform part of the Republic of Bashkortostan. Based on the research results, geological preconditions were established that determined the formation of geological objects with anomalous properties in the upper part of the section, which can negatively affect the results of seismic exploration. The minimum required set of geological and geophysical information has been determined and an algorithm has been developed that makes it possible to identify and map zones of their development. The research results were used in the process of desk processing of materials from 3D work using common depth point method when calculating static corrections, which made it possible to minimize the influence of velocity inhomogeneities and increase the confirmability of structural plans during seismic exploration. This approach was recommended for use throughout the platform part of the Republic of Bashkortostan.

References

1. Abdrakhmanov R.F., Martin V.I., Popov A.P. et al., Karst Bashkortostana (Karst of Bashkortostan), Ufa: Informreklama Publ., 2002, 384 p.

2. Maksimovich G.A., Entsov I.I., Metodika izucheniya karsta (Methodology for studying karst), Part 5. Geofizicheskie metody (Geophysical methods), Perm’, 1963, 98 p.

3. Maksimovich G.A., Entsov I.I., Metodika izucheniya karsta (Methodology for studying karst), Part 4. Paleokarst i karst (Paleokarst and karst), Perm’, 1963, 81 p.

4. Nasyrov S.S., Kuryaeva V.V., Khat’yanov F.I., Ispol’zovanie kompleksa geofizicheskikh metodov razvedki s tsel’yu izucheniya drevnikh erozionnykh vrezov i paleokarsta v Bashkirskom Priural’e (Using a complex of geophysical exploration methods to study ancient erosion incisions and paleokarst in the Bashkir Urals), Collected papers “Karst Bashkirii” (Karst of Bashkiria), Ufa, 1971, pp. 88–91.

5. Martin V.I., Klassifikatsiya karsta Bashkirii (Classification of karst in Bashkiria), Collected papers “Karst Bashkirii” (Karst of Bashkiria), Ufa, 1971, pp. 10–13.

6. Levorsen A.I., Geologiya nefti (Petroleum Geology), Moscow: Gosoptekhizdat Publ., 1958, 488 p.

7. Zalyaev N.Z., Metodika avtomatizirovannoy interpretatsii geofizicheskikh issledovaniy skvazhin (Methodology for automated interpretation of geophysical well surveys), Minsk: Universitetskoe Publ., 1987, 142 p.

The article is devoted to the issues of justifying the unit cost of well construction when preparing project documents for the development of hydrocarbon deposits. Existing approaches to calculating capital investments for drilling wells are reviewed and analyzed, and the main disadvantages and advantages are identified. The analysis carried out by the authors showed that the actual drilling costs of the subsoil user differ significantly from the calculated ones, which significantly affects the assessment of drilling costs and the assessment of the volume of economically recoverable reserves. In order to increase the accuracy of calculations, the authors made proposals for improving approaches to justifying the cost of drilling. The article discusses the main types of services and cost items that form the cost of well drilling, and shows the structure of drilling costs in various geographic regions. Based on the analysis, the main drivers for each cost item that forms the cost of well construction were identified. The authors propose to use price groups of wells when justifying the cost of drilling, which increases the justification of the projected investment in drilling. A practical example shows the calculation of the cost of well drilling, a comparative analysis of the use of various approaches is made, on the basis of which the authors conclude that the maximum correspondence of the projected costs to the actual data is ensured by the approach proposed by the authors. As an evidence base, an example is considered showing the change in the volume of profitable reserves, capital investments, income of the subsoil user and the state over a profitable period using the traditional approach to justifying the cost of wells drilling proposed by the authors.

References

1. Resolution of the Government of the Russian Federation of November 30, 2021 No 2127 “O poryadke podgotovki, soglasovaniya i utverzhdeniya tekhnicheskikh proektov razrabotki mestorozhdeniy poleznykh iskopaemykh, tekhnicheskikh proektov stroitel’stva i ekspluatatsii podzemnykh sooruzheniy, tekhnicheskikh proektov likvidatsii i konservatsii gornykh vyrabotok, burovykh skvazhin i inykh sooruzheniy, svyazannykh s pol’zovaniem nedrami, po vidam poleznykh iskopaemykh i vidam pol’zovaniya nedrami” (On the procedure for the preparation, coordination and approval of technical projects for the development of mineral deposits, technical projects for the construction and operation of underground structures, technical projects for the liquidation and conservation of mine workings, boreholes and other structures related to the use of subsoil, by type of mineral resources and type of subsoil use).

2. Pravila podgotovki tekhnicheskikh proektov razrabotki mestorozhdeniy uglevodorodnogo syr’ya (Rules for the preparation of technical projects for the development of hydrocarbon deposits): approved by order of the Ministry of Natural Resources of Russia No. 639 on September 20, 2019, URL: http://www.consultant.ru/document/cons_doc_LAW_334817/

3. Metodicheskie rekomendatsii po otsenke effektivnosti investitsionnykh proektov (Methodical recommendations according to efficiency of investment projects), Moscow: Publ. of Ministry of Economics RF, Ministerstvo finansov RF, 2000.

The continued growth in the volume of prospecting and exploration leads to stricter requirements for the quality of well drilling, regulation of the rheological properties of weighted cement mortars, which is key for ensuring safety, drilling stability and preventing complications, as well as reducing the time to eliminate accidents. The main objective of the study is to study the use of a hyperplasticizer reagent as an additive to cement mortars made of pure portland cement, to obtain weighted solutions of high density with the necessary rheological properties. These grouting solutions are aimed at developing an increase in the spreadability of cement mortar and an increase in the strength of cement stone, which ensures high-quality fastening of casing columns in the intervals of zones with difficult mining and geological conditions and abnormally high pressure in ultra-deep wells. In laboratory conditions, using various instruments and equipment, a study based on standard methods of analysis of grouting mortar and properties of cement stone was carried out with the addition of a hyperplasticizer reagent, which made it possible to plasticize grouting solutions, increase spreadability and make it possible to regulate the density of weighted solutions. In the course of the study, the important results of laboratory tests for regulating the rheological properties of weighted grouting solutions with the addition of a hyperplasticizer reagent were obtained. It was found that the hyperplasticizer reagent effectively plasticizes grouting solutions, increasing their spreadability and reducing the water-cement ratio, which leads to the formation of a cement stone with increased strength. The results of industrial testing of the reagent during cementing of the production column in one of the wells confirmed the possibility of preparing a weighted slurry with a density of 2,40 g/cm3, thereby ensuring the successful performance of cementation work under high pressure conditions. This research justifying the use of a hyperplasticizer reagent in weighted cement mortars will be of great importance in well completion, and will also lead to an improvement in the quality of the cementing technology and reliable fastening of casing columns, especially in difficult mining and geological conditions of areas with abnormally high reservoir pressures, thereby improving the creation of high-strength cement stones while drilling of wells.

References

1. Deryaev A.R., Analysis of the opening of zones with abnormally high reservoir pressures in the oil and gas fields of the Western part of Turkmenistan (In Russ.), SOCAR Proceedings Special, 2023, no. 2, pp. 22–27, DOI: http://doi.org/10.5510/OGP2023SI200871

2. Aghayev B.S., Method for operational forecasting of high-pressure zones in oil and gas wells, Problems of Information Technology, 2022, V. 14(1), p. 29-36,

DOI: http://doi.org/10.25045/jpit.v14.i1.05

3. Deryaev A.R., Well trajectory management and monitoring station position borehole (In Russ.), SOCAR Proceedings Special Issue, 2023, no. 2, pp. 1–6,

DOI: http://doi.org/10.5510/OGP2023SI200870

4. Kumar S., Bera A., Shah S.N., Potential applications of nanomaterials in oil and gas well cementing: Current status, challenges and prospects, Journal of Petroleum Science and Engineering, 2022, V. 213, DOI: http://doi.org/10.1016/j.petrol.2022.110395

5. Beskopylny A., Stel’makh S.A., Shcherban E.M. et al., Nano modifying additive micro silica influence on integral and differential characteristics of vibrocentrifuged concrete, Journal of Building Engineering, 2022, V. 51, DOI: http://doi.org/10.1016/j.jobe.2022.104235

6. Hafezi S., Real-time detection of drilling problems & issues during drilling by listing & using their signs both on the surface and downhole: Master’s thesis, NTNU, 2023.

7. Deryaev A.R., Features of forecasting abnormally high reservoir pressures when drilling wells in the areas of Southwestern Turkmenistan (In Russ.), SOCAR Proceedings, 2023, Special Issue No. 2, pp. 7-12, DOI: http://doi.org/10.5510/OGP2023SI200872

8. Eren T., Suicmez V.S., Directional drilling positioning calculations, Journal of Natural Gas Science and Engineering, 2020, V. 73,

DOI: http://doi.org/10.1016/j.jngse.2019.103081

9. Deshmukh V., Dewangan S.K., Review on various borehole cleaning parameters related to oil and gas well drilling, Journal of the Brazilian Society of Mechanical Sciences and Engineering, 2022, V. 44(5), DOI: http://doi.org/10.1007/s40430-022-03501-2

10. Deryaev A.R., Selection of drilling mud for directional production and evaluation wells (In Russ.), SOCAR Proceedings, 2023, no. 3, pp. 51-57, DOI: http://doi.org/10.5510/OGP20230300886

11. Mansouri V., Khosravanian R., Wood D.A., Aadnøy B.S., Optimizing the separation factor along a directional well trajectory to minimize collision risk, Journal of Petroleum Exploration and Production Technology, 2020, V. 10, pp. 2113–2125, DOI: http://doi.org/10.1007/s13202-020-00876-7

12. Ahmed A., Abdelaal A., Elkatatny S., Evaluation of hematite and Micromax-based cement systems for high-density well cementing, Journal of Petroleum Science and Engineering, 2022, V. 220, DOI: http://doi.org/10.1016/j.petrol.2022.111125

13. Xin Chen, Chengwen Wang, Yucheng Xue et al., A novel thermo-thickening viscosity modifying admixture to improve settlement stability of cement slurry under high temperatures, Construction and Building Materials, 2021, V. 295, DOI: https://doi.org/10.1016/j.conbuildmat.2021.123606

14. Deryaev A.R., Features of the construction of directional deep wells in Turkmenistan (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2024, no. 2, pp.43-47,

DOI: https://doi.org/10.24887/0028-2448-2024-2-43-47.

15. Kong B., Chen Z., Chen S., Qin T., Machine learning-assisted production data analysis in liquid-rich Duvernay Formation, Journal of Petroleum Science and Engineering, 2021, V. 200, DOI: http://doi.org/10.1016/j.petrol.2021.108377

16. Jing Ni, Gang-Lai Hao, Jia-Qi Chen et al., The optimisation analysis of sand-clay mixtures stabilised with xanthan gum biopolymers, Sustainability, 2021, V. 13(7),

DOI: http://doi.org/10.3390/su13073732

17. Chilingarian G.V., Fertl W.H., Formation pressures, abnormal, In: Applied Geology. Encyclopedia of Earth Sciences Series: edited by Finkl C., Springer, Boston, MA., 1984, pp. 173-184, DOI: https://doi.org/10.1007/0-387-30842-3_23

18. Cheng Lu, Yuxuan Xia, Xiaoxiao Sun et al., Permeability evolution at various pressure gradients in natural gas hydrate reservoir at the Shenhu area in the South China Sea, Energies, 2019, V. 12(19), DOI: http://doi.org/10.3390/en12193688

The publication discusses the methodology used by Gazprom PJSC to calculate the productivity of gas-saturated reservoirs according to research data by a reservoir tester on a cable with hydrodynamic logging (TRC-HDL) in an open well bore. In the conditions of the Arctic shelf, on the example of the Kara Sea, in the short autumn-summer navigation season it is possible to drill one offshore well with a depth of 2500 meters and test a maximum of two pay zones in a full-cycle column. On the shelf of the Yamal Peninsula in the Kara Sea, wells exposed 10 or more productive formations, which made it difficult to complete the geological prospecting completely. Therefore, previously, a deep-sea well was drilled to the design bottom in one year (season), preserved and the next year tests were carried out in a column. In this case, the cost of well construction increased at least 1,6 times. At the same time, there were risks of damage to the wellhead by ice bodies (icebergs, etc.). Aquifers with saturation unclear according to geophysical well logging were also often tested in the column. Methodological recommendations for substantiating the calculated parameters of deposits in terrigenous deposits according to geophysical well logging data and new TRC-HDL methods when registering and transferring raw hydrocarbons to industrial reserve categories make it possible to avoid testing aquifers in a column, take conditioned samples of reservoir fluids, and also determine the productivity of the interval based on actual well testing data and to transfer raw hydrocarbons to the industrial category C1 and, accordingly, to complete the construction of an offshore well in one drilling season per navigation (2,5–3 months) without significant loss of geological information. The article provides a brief description of the methodology. A brief analysis of the conducted research on offshore wells of the Kara Sea is presented.

References

1. Metodicheskie rekomendatsii po primeneniyu klassifikatsii zapasov i resursov nefti i goryuchikh gazov (Guidelines on the application of oil and combustible gas resources and reserves classification), Moscow: Publ. of Russian Ministry of Natural Resources, 2016.

2. Trebovaniya k sostavu i pravilam oformleniya predstavlyaemykh na gosudarstvennuyu ekspertizu materialov po podschetu zapasov nefti i goryuchikh gazov (Requirements for the composition and rules of registration of materials submitted for state examination on the calculation of oil and combustible gas reserves): approved by order of the Ministry of Natural Resources of Russia No. 564 on December 28, 2015, URL: http://www.consultant.ru/document/cons_doc_LAW_112447/

3. Pravila podgotovki tekhnicheskikh proektov razrabotki mestorozhdeniy uglevodorodnogo syr’ya (Rules for the preparation of technical projects for the development of hydrocarbon deposits): approved by order of the Ministry of Natural Resources of Russia No. 639 on September 20, 2019, URL: http://www.consultant.ru/document/cons_doc_LAW_334817/

4. Metodicheskie rekomendatsii po podgotovke tekhnicheskikh proektov razrabotki mestorozhdeniy uglevodorodnogo syr’ya (Methodological recommendations for the preparation of technical projects for the development of hydrocarbon deposits), Moscow: Publ. of Russian Ministry of Natural Resources, 2016.

5. Abdrakhmanova L.G., Akhmedsafin S.K., Blinov V.A. et al., Metodicheskie rekomendatsii po obosnovaniyu podschetnykh parametrov zalezhey v terrigennykh otlozheniyakh po dannym GIS i novym metodam GDK-OPK pri postanovke na uchet i perevode UVS v promyshlennye kategorii zapasov (Methodological recommendations for substantiating the calculated parameters of deposits in terrigenous deposits using well logging data and new methods of hydrodynamic logging and formation testing when registering and transferring hydrocarbons to industrial categories of reserves), Moscow: Publ. of Gazprom, 2015, 64 p.

6. Khoshtariya V.N., Khaziev M.I., Svikhnushin N.M. et al., Opportunities for borehole productivity estimation (from wireline formation testers data) by hydrodynamical simulation with the Petrel software (In Russ.), Karotazhnik, 2017, no. 9, pp. 12–20.

7. Khoshtariya V.N., Martyn A.A., Kurdin S.A. et al., Wireline formation tester data for reserves classification: The Russian methodology and experience (In Russ.),

PE-181975-MS, 2016, DOI: https://doi.org/10.2118/181975-MS

8. Cherepanov V.V., Akhmedsafin S.K., Rybal’chenko V.V. et al., Geological exploration of PJSC «Gazprom» in the arctic shelf of the Russian federation: Results and prospects (In Russ.), Stroitel’stvo neftyanykh i gazovykh skvazhin na sushe i na more, 2018, no. 7, pp. 47–56, DOI: https://doi.org/10.30713/0130-3872-2018-7-47-56

Due to the depletion of traditional oil and gas reservoirs and a change in volumes of production, therefore issues of extracting oil from oil and gas source rocks are becoming more important. The petroleum industry has to constantly develop various pilot trials to develop technology for maintaining production performance. Since 2018 pilot works have been launched to develop approaches to the domanic deposits development in the Samara and Orenburg regions operated by Rosneft Oil Company. Hydraulic fracturing operations have been performed in over 20 wells for the last 5 years in these regions. The paper presents the analysis results of the hydraulic fracturing operations in 4 vertical wells. Operations in 3 wells were completed with crosslinked guar-based fluid, whereas 1 well was fractured with the use of polyacrylamide based high viscosity friction reducer (HVFR). A one-dimensional geomechanical model of the nearest well was used as a basis for the hydraulic fracturing modeling of wells participating in the pilot project. As the result of this study it was found that integrated approach should be conducted while preparing to hydraulic fracturing operations in domanic deposits, including the laboratory core studies, 1D geomechanical modeling, fracture geometry measurements, proper perforation interval selection, bottom hole gauge use, fracturing technology selection (fluid type, proppant type and mass, slurry rate, etc.), use of surface and downhole equipment rated for 100 MPa. Further research and pilot works are necessary to determine the optimal well completion and hydraulic fracturing technology for the domanic deposits development in the Samara and Orenburg regions. The goal of this work is to define factors influencing the technological success of hydraulic fracturing in domanic deposits.

References

1. Economides M.J., Nolte K.G., Reservoir stimulation, JohnWilley & Sons, Ltd., New York, 2000, 848 p.

2. Stupakova A.V., Kalmykov G.A. et al., Domanic deposits of the Volga-Ural basin - types of section, formation conditions and prospects of oil and gas potential

(In Russ.), Georesursy, 2017, Special Issue, pp. 112–124.

3. Fjar E., Holt R.M., Raaen A.M., Horsrud P., Petroleum related rock mechanics. – Elsevier, 2008. – 514 p.

4. Roberts G.A., Chipperfield S.T., Miller W.K., The evolution of a high near-wellbore pressure loss treatment strategy for the Australian cooper basin, SPE-63029-MS, 2000, DOI: https://doi.org/10.2118/63029-MS

5. Zoback M., Kohli A., Unconventional reservoir geomechanics: Shale gas, tight oil, and induced seismicity, 2019, 496 p., DOI: https://doi.org/10.1017/9781316091869

6. Barree R.D., Miskimins J.L., Gilbert J.V., Diagnostic fracture injection tests: Common mistakes, misfires, and misdiagnoses, SPE-169539-PA, 2015,

DOI: https://doi.org/10.2118/169539-PA

7. Vinod P.S., Flindt M.L., Card R.J., Mitchell J.P., Dynamic fluid-loss studies in low-permeability formations with natural fractures, SPE-37486-MS, 1997,

DOI: https://doi.org/10.2118/37486-MS

8. 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.

9. Miller B.D., Warembourg P.A., Prepack technique using fine sand improves results of fracturing and fracture acidizing treatments, SPE-5643-MS, 1975,

DOI: https://doi.org/10.2118/5643-MS

Hydrocarbon filed development is the multistage process, which includes the stages of: growing production, maximum production plateau, decreasing production and the final stage of development. Enhancement of a degree and quality of residual oil production at the final development stage is the important aspect for the improved efficiency of the field development. Decrease of well flow decline rates, maintenance of production target indicators, and thus, improved yield and increased ultimate recovery factor are achieved through the justification and implementation of complex well intervention programs and methods to enhance oil recovery. Therefore, a successful field development requires constant upgrading of technologies and operation methods, which benefit in optimized production processes and increased total volume of produced hydrocarbon. The process of selecting and planning the well intervention programs in offshore fields has its own key features, which should be considered during all decision-making phases, starting from the analysis of geological and field criteria for selecting the well candidates to the conditions for implementing the proposed solutions. Vietsovpetro JV specialists have revised the set of logging data from clastic reservoirs, which allowed defining the structure and volume of reserves after the re-interpretation of geophysical information. Significant influence of a drilling mud invasion zone to the records of lateral log, as well as a presence of polymathic sandstones in a cross-section, made it difficult to interpret the standard well logging and correctly specify the oil saturated intervals. Implementation of a petrophysical modelling and processing of deep/shallow electro logging methods allowed resolving the uncertainties. As a result, the geologic and hydrodynamic models have been built in accordance with the new understanding of the reservoir, as well as the new well intervention program has been proposed to maintain the oil production levels and to increase development of residual oil from White Tiger field of Socialist Republic of Vietnam continental shelf. The approach, described in this article, can be expanded to the similar offshore projects.

References

1. Kudryashov S.I., Le Viet Hai, Fam Suan Shon et al., The White Tiger field: from the history of development to development prospects (dedicated to the 40th anniversary of the Vietsovpetro joint venture) (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 6, pp. 6-14.

2. Merkulov V.P., Posysoev A.A., Otsenka plastovykh svoystv i operativnyy analiz karotazhnykh diagramm (Evaluation of reservoir properties and operational analysis of well logs), Tomsk: Publ. of TPU, 2004, 113 p.

3. Kovalenko K.V., Sistema petrofizicheskogo obespecheniya modelirovaniya zalezhey nefti i gaza na osnove effektivnoy poristosti granulyarnykh kollektorov (Petrophysical support system for modeling oil and gas reservoirs based on the effective porosity of granular reservoirs): thesis of doctor of geological and mineralogical science, Moscow, 2015.

4. Darling T., Well logging and formation evaluation, Elsevier Science, 2005, 336 p.

5. Lubnin A.V., Justification of technical and economic criteria of re-equipment wells from gas lift operation to ESP (In Russ.), PROНЕФТЬ. Профессионально о нефти = PROneft. Professionally about Oil, 2023, V. 8, no. 1, pp. 98-106, DOI: https://doi.org/10.51890/2587-7399-2023-8-1-98-106

6. Shchekin A.I., Grishchenko E.N., Lotfullin Sh.R. et al., Applying statistical and oilfield methods in predicting waterflood induced hydraulic fractures in the injection wells (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2016, no. 9, pp. 78-81.

The paper compares conventional and alternative methods of hydraulic fracturing (fracking) in wells with close water-oil contact in low-permeability reservoirs of the Tournaisian Stage featuring high risk of formation's bottom water breakthrough. Developing this type of reservoirs is not as efficient as other structures in terms of drilling, development control by means of formation pressure maintenance system and hydrodynamics of products extraction due to the peculiarities of geological structure and poroperm properties of formations. The theory part of this article presents typified data on critical specific resistivity values of carbonate deposits of oil fields in the south-eastern part of the Republic of Tatarstan used to estimate fluid saturation of rocks distributed by oil saturation ratio depending on induction values of electrometry in an open hole. The article also provides information on the geological structure of the Tournaisian Stage sediments with more extensive breakdown into Kizelovsky, Cherepetsky, Upinsky and Malevsky horizons, and briefly outlines the theory of hydraulic fracturing in the context of the peculiarities of fluid percolation during modeling of fracturing processes and their subsequent implementation, and demonstrate the main drawbacks and advantages of the technology. The paper presents a comparative analysis of hydraulic fracturing processes using conventional (guar gum) technology and an alternative technology based on hydrophobically associative polyacrylamide with distinct surfactant properties in carbonate reservoirs of the Tournaisian stage of the Rzhavetskaya structure of the Letneye oilfield in the Republic of Tatarstan. The results of the survey suggest that the alternative technology makes it possible to implement gentle fracturing by reducing the risk of fracture penetration into the water-bearing zone of the reservoir, including the peripheral areas of deposits with minor oil-saturated thickness, to bring the oil production rate to a profitable level due to the absence of colmatation (clogging) by guar within the target interlayers, to increase the number of wells eligible for hydraulic fracturing and to bring into development the reserves that were previously considered substandard.

References

1. Yunusov I.M., Takhautdinov R.Sh., Novikov M.G. et al., Assessment of man-made fracturing of carbonate reservoirs of the western slope of the South-Tatar arch based on the results of multi-stage hydraulic fracturing (In Russ.), Stroitel’stvo neftyanykh i gazovykh skvazhin na sushe i na more, 2022, no. 3(351), pp. 63–68.

DOI: https://doi.org/10.33285/0130-3872-2022-3(351)-63-68

2. Tekhnologicheskiy proekt razrabotki Krasnooktyabr’skogo neftyanogo mestorozhdeniya AO “Sheshmaoyl” (Technological project for the development of the Krasnooktyabrsky oil field of Sheshmaoil JSC), Minutes of the Central Committee of Rosnedra No. 7335 dated November 15, 2018.

3. Dopolnenie k tekhnologicheskoy skheme razrabotki Letnego neftyanogo mestorozhdeniya AO “Sheshmaoyl” (Addition to the technological scheme for the development of the Letney oil field of Sheshmaoil JSC), Minutes of the Central Committee of Rosnedra No. 7385 dated December 11, 2018.

4. Dopolnenie k tekhnologicheskoy skheme razrabotki Novo-Sheshminskogo neftyanogo mestorozhdeniya AO “Sheshmaoyl” (Addition to the technological scheme for the development of the Novo-Sheshminskoye oil field of Sheshmaoil JSC), Minutes of the Central Committee of Rosnedra No. 7356 dated November 29, 2018.

5. Tekhnologicheskiy proekt razrabotki Severnogo neftyanogo mestorozhdeniya AO “Sheshmaoyl” (Technological project for the development of the Northern oil field of Sheshmaoil JSC), Minutes of the Central Committee of Rosnedra No. 7923 dated September 18, 2018.

6. Muslimov R.Kh., Abdulmazitov R.G., Khisamov R.B. et al., Neftegazonosnost’ Respubliki Tatarstan. Geologiya i razrabotka neftyanykh mestorozhdeniy (Oil and gas bearing of the Republic of Tatarstan. Geology and development of oil fields), Part 2, Kazan’: FEN Publ., 2007, 524 p.

7. Davletov M.Sh., Lysenkov A.V., Yunusov I.M. et al., Comparative analysis of well flow testing with respect to porosity and permeability properties of reservoirs by direct and indirect methods on fields confined to the slopes of the South Tatar Arch (In Russ.), Problemy sbora, podgotovki i transporta nefti i nefteproduktov = Problems of Gathering, Treatment and Transportation of Oil and Oil Products, 2022, no. 6 (140), pp. 66–82, DOI: https://doi.org/10.17122/ntj-oil-2022-6-66-82

8. Zoback M.D., Reservoir geomechanics, Stanford University, California, 2007, DOI: https://doi.org/10.1017/CBO9780511586477

9. Isaev A.A., Takhautdinov R.Sh., Malykhin V.I. et al., A set of options for stimulation of wells, SPE-212098-MS, 2022, DOI: https://doi.org/10.2118/212098-MS

10. Economides M., Oligney R., Valko P., Unified fracture design. Bridging the gap between theory and practice, Orsa Press, Alvin, Texas, 2002, 262 p.

Carbonate reservoirs worldwide are the main oil production resources due to their large scale and wide spread. One of the challenges in the carbonates development is increasing waterflooding efficiency. This paper considers the issue of a water loss to an underlying aquifer through the fractures in non porous carbonates that open at a high water injection pressure. The results of the field data analysis allow suggesting that carbonate rocks are fractured under conditions of waterflooding. These fractures may cause a loss of injected water. Consequently, the oil recovery efficiency may also decrease. In order to solve this problem in the oilfields of the Republic of Bashkortostan, the water loss percentage was calculated using a material balance analysis. Also, a conceptual model of a fluid flow during a waterflooding of the tournaisian carbonate reservoir of Tujmazinskoe oilfield was proposed. On the basis of this model an algorithm of the water loss estimation was developed. The new algorithm takes into account the results of well testing and a variation of geological parameters, and can increase the accuracy of calculations for the carbonate reservoirs with uncertainties in the aquifer influx and a flow behind casing. The results of this research could be used to estimate injection rates for carbonate reservoirs of the oilfields of the Republic of Bashkortostan in the conditions of water loss to an underlying aquifer.

References

1. Carbonate reservoirs – Overcome challenging heterogeneity, URL: https://www.slb.com/technical-challenges/carbonates#related-information.

2. Yakupov R.F., Mukhametshin V.Sh., Problem of efficiency of low-productivity carbonate reservoir development on example of Turnaisian stage of Tuymazinskoye field (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2013, no. 12, pp. 106–110.

3. Akbar M. et al., A snapshot of carbonate reservoir evaluation, Oilfield Review, 2000, V. 12, no. 4, pp. 20–41.

4. Zheng-Xiao Xu et al., A review of development methods and EOR technologies for carbonate reservoirs, Petroleum Science, 2020, V. 17, no. 4, pp. 990–1013,

DOI: https://doi.org/10.1007/s12182-020-00467-5

5. Akhmetzyanov R.R. et al., How to increase the efficiency of the reservoir pressure maintenance system during field development (In Russ.), Territoriya Neftegaz, 2015, no. 2, pp. 14–17.

6. Dake L.P., The practice of reservoir engineering, Elsevier, 2001, 572 p.

7. Prilozhenie 13 k instruktsii PAO “NK “Rosneft’” (Appendix 13 to the instructions of Rosneft PJSC), Rukovodstvo pol’zovatelya informatsionnoy sistemy “Kompleks instrumentov dlya neftyanogo inzhiniringa” (User’s guide for the Information System “Complex of Tools for Petroleum Engineering”), Modul’ material’nyy balans (Material balance module). Ver. 2.0, Moscow: Publ. of Rosneft Oil Company, 2020. – 26 p.

The article is devoted to studying the issues of segregation and relaxation of reserves and taking into account these effects when forming a program of development optimization of the production target BS10 of the Mamontovskoye field, which is at a late stage of development. The results of the analysis of actual drilling data from wells and sidetracks, sampling and testing of core material, studies of transit wells using carbon-oxygen logging with the subsequent implementation of measures to transfer them into production at the production target BS10 confirm the theoretical ideas about the effects under consideration occurring in the formation. The processes of relaxation of reserves in the reservoirs of the production target BS10 lead to the localization of oil pillars in the top part of the reservoir, which is additionally confirmed by the results of hydrodynamic modeling. Taking these effects into account is crucial when planning the most efficient drilling activities. For offshore objects in Western Siberia, which are at a late stage of development, where fresh water was injected to maintain reservoir pressure, one of the effective methods for determining the current saturation of the formation in conditions of low salinity of formation waters is carbon-oxygen logging. The results of research and commissioning of wells indicate a connection between the residual oil-saturated thicknesses and their starting parameters. Logging shows a high differentiation of the current oil saturation along the section with the accumulation of hydrocarbons near the top of the formation. Based on the results of core studies, a vertical differentiation of the fluid saturation value in the formation can be traced. Oil shows are contrastingly illuminated in the ultraviolet glow in the upper part of the section, while lower down the section the glow is less pronounced, which indicates the depletion of the initial recoverable reserves in the lower part of the formation. The glow data correlates well with the interpretation results of geophysical studies. The positive experience gained while drilling horizontal wells in a separate section of the production target BS10 served as a decisive factor for starting to scale up infill drilling to the production target as a whole. The results of the work are applicable to a number of production targets which are at a late stage of development and are characterized by similar filtration and capacitance properties in order to increase the efficiency of production of current reserves.

References

1. Khisamiev T.R., Khabibullin G.I., Shaykhatdarov D.R. et al., Prospects for infill drilling of wells at a late stage of development on the example of the BS10 object of the Mamontovskoye field (In Russ.), Neftegazovoe delo, 2023, V. 21, no. 6, pp. 103–115, DOI: https://doi.org/10.17122/ngdelo-2023-6-103-115

2. Suleymanova M.V., Mironenko A.A., Safin A.Z. et al., Oil migration on the last stage of oil fields development (In Russ.), Ekspozitsiya Neft’ Gaz, 2023, no. 1, pp. 72–75, DOI: http://doi.org/10.24412/2076-6785-2023-1-72-75

3. Gafarov Sh.A., Yusupova E.R., The oils composition and oil reservoirs influence to capillary-gravitational segregation of hydrocarbons (In Russ.), Neftegazovoe delo, 2010, V. 9, no. 1, pp. 35–38.

4. Eremenko N.A. et al., Izvlechenie nefti iz vyrabotannykh zalezhey posle ikh pereformirovaniya (Extraction of oil from depleted deposits after their reformation), Moscow: Publ. of VNIIOENG, 1978. - 59 s.

5. Krylov A.P., About some issues of oil recovery (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 1974, no. 3, pp. 37–40.

6. Lozin E.V., Arzhilovskiy A.V., Chervyakova A.N. et al., About hydrodynamics effect after plural outage of wells in 90’s last century (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2018, no. 6, pp. 62–65, DOI: http://doi.org/10.24887/0028-2448-2018-6-62-65

7. Shchelkachev V.N., Itogi vypolnennykh v voennykh usloviyakh (1941-1944) issledovatel’skikh rabot na groznenskikh neftyanykh promyslakh (The results of research on the Grozny oil fields which was done in time of war (1941-1944)), In: Vazhneyshie printsipy nefterazrabotki. 75 let opyta (The most important principles of oil production. 75 years of experience), Moscow: Neft’ i gaz Publ., 2004, pp. 261–263.

8. Khalimov E.M., Vtorichnaya razrabotka neftyanykh mestorozhdeniy (Secondary development of oil fields), St. Petersburg: Nedra Publ., 2006, 361 p.

9. Khalimov E.M., Lozin E.V., Vtorichnaya razrabotka neftyanykh mestorozhdeniy Bashkortostana (Secondary development of oil fields of Bashkortostan), ST. Petersburg: Publ. of VNIGRI, 2013, 182 p.

10. Povzhik P.P., Kudryashov A.A., Secondary development as one of the main methods of oil recovery ratio enhancement (In Russ.), Oborudovanie i tekhnologii dlya neftegazovogo kompleksa, 2009, no. 6, pp. 61–64.

11. Shaykhutdinov T.F., Yarkeeva N.R., Analiz osnovnykh prichin povysheniya obvodnennosti produktsii dobyvayushchikh skvazhin na neftyanykh mestorozhdeniyakh (Analysis of the main reasons for the increase in water cut in production wells in oil fields), Collected papers “Innovatsii i naukoemkie tekhnologii v obrazovanii i ekonomiki” (Innovation and high technology in education and economics), Proceedings of VIII International scientific, practical and methodological conference, Ufa, 2019, pp. 206–209.

12. D’yachuk I.A., Formirovanie sistem razrabotki neftyanykh mestorozhdeniy na zaklyuchitel’noy stadii v usloviyakh zavodneniya (Formation of oil field development systems at the final stage under flooding conditions), Ufa: Publ. of USPTU, 2015, 275 p.

The article discusses the implementation of information system «Parus» for production activity monitoring in a group of oil-and-gas design institutes of Rosneft Oil Company. The system operates various types of data, such as oil production plans, business plans, project plans and projected and actual data of projects delivery. The main users of the system are project managers, assistants and top-managers. The paper reveals the main functionality of the developed software, including the tracking of changes in key indicators of production activities what enables retrospective and comparative data analysis of the datasets in the form of reports and dashboards. Particular attention is paid to the application of the «Parus» tools to processes of monitoring and assessing the project activities effectiveness as well as integration of the «Parus» into other systems of Rosneft corporate environment: the «Sapsan-2020» engineering document management system, local systems for contract management, the «Parus-Monitoring» data consolidation system and the «Sapsan-M» corporate portal. The implementation of the software provided Rosneft Oil Company with a new efficient means of projects control and reducing delays in projects delivery through prompt implementation of corrective actions. The implemented automation of processes made it possible to increase the efficiency of risk management and speed of decision-making as well as create a transparent reporting system in the company.

References

1. Dakueva E.R., Machueva D.A., Research and implementation of a system for monitoring the activities of an enterprise (In Russ.), Universum: tekhnicheskie nauki, 2021, no. 11(92), URL: https://7universum.com/ru/tech/archive/item/12613

2. Sistema sbalansirovannykh pokazateley (BSC). Sistemy kachestva (Balanced score card (BSC). Quality systems), 2011, URL: http://www.qm-s.com/it_consulting/balanced_scorecard_bsc

3. Gromakov E.I., Aleksandrova T.V., Liepin’sh A.V., Malyshenko A.M., Avtomatizirovannyy monitoring klyuchevykh pokazateley deyatel’nosti proektnoy organizatsii (In Russ.), Izvestiya Tomskogo politekhnicheskogo universiteta. Inzhiniring georesursov = Bulletin of the Tomsk Polytechnic University. Geo Assets Engineering, 2012, V. 321, no. 5, pp. 173-178.

4. Bobkov O., Informatsionnye tekhnologii v upravlenii organizatsiey: rol’, tsel’ i obshchaya kharakteristika upravlencheskikh IT (Information technology in organization management: role, purpose and general characteristics of management IT), URL: https://www.cleverence.ru/articles/auto-busines/informatsionnye-tekhnologii-v-upravlenii-organizatsi...

5. Garrison R.H., Noreen E.W., Brewer P.C., Managerial accounting, McGraw-Hill/Irwin, 2006, 863 p.

The article shows the results of combined analysis of statistical data and the laboratory studies of fluid seepage under the conditions when the gas is artificially pumped from the annular space of a well. As a part of statistical analysis, the performance profiles of producing wells of Sheshmaoil JSC, Ideloil JSC, Geology JSC and Geotech JSC operated by sucker rod pumping units and fitted with compressor units for extraction of annular gas have been examined. 438 wells were selected for analysis. In 25 % of wells the pump location depth is below the depth of the producing reservoir, and in 10 % of wells the bottomhole pressure is zero – these are the wells where the fluid dynamic level is located below the depth of the top of the formation. When the gas is pumped from the wellbore annulus, the bottomhole pressure of these formations corresponds to the gas pressure in the annulus and almost equals zero. For wells fitted with compressor units for extraction of annular gas, stable performance of reservoirs is observed even under the conditions of extremely low values of bottomhole pressure, particularly of oil-saturated reservoirs with low water cut (average value is 33 %). Firstly, this is due to the low gas-oil ratio of the crude oil (3,7 m3/t for the sample under consideration), and, secondly, due to the beneficial role of gas pumping and its effective removal from the reservoir. The gas released in the formation shall be recovered from the bottom-hole formation zone nearest to the well and shall retain fluid relative permeability. Besides, the gas evacuated using compressor units for extraction of annular gas will not enter the pump thereby having no adverse effect on its operation, which makes it possible to maintain a low value of pressure at the pump inlet. For reference, the average pressure at the pump inlet in wells with zero bottomhole pressure was about 0,65 MPa, while across the entire sample of examined wells the pressure was 1,4 MPa.

The method has been proposed to calculate the inlet pressure based on the data of field measurements (the gas pressure in the annular space and the dynamic level) using the linear dependence of the inlet pressure on these parameters. The results of statistical analysis indicate the applicability of the linear dependence for calculating the pump inlet pressure. The inlet pressure is generated as the aggregate of the annular gas pressure (equal to zero after pumping) and the pressure of the fluid column in the annular space between the depth of the dynamic level and the depth of downhole sucker rod pump location. The effect of gas pressure in the annulus on the generation of bottomhole pressure was examined, provided that the gas is pumped from a wellbore. It has been established that the nature of influence of annular gas pressure on bottomhole gas pressure is determined by the relative location of the dynamic level, the depth of pump setting, and the depth of the active reservoir. If the downhole sucker rod pump is placed below the depth of the producing formation, a situation may occur where the dynamic level will be below the depth of the formation. The analysis of well operation regimes revealed 10 % of wells operating under the mentioned mode. For the wells where the dynamic level is below the formation depth, the bottomhole pressure will be the same as the annular gas pressure. However, after pumping, the bottomhole pressure will be almost zero. For the 10 % sample of wells with the dynamic level below the formation depth, the average annular gas pressure (and, respectively, the bottomhole pressure) was equal to 0,03 MPa.

References

1. Isaev A.A., Takhautdinov R.Sh., Malykhin V.I., Sharifullin A.A., Oil production stimulation by creating a vacuum in the annular space of the well, SPE-198401-MS, 2019, DOI: https://doi.org/10.2118/198401-MS

2. Isaev A.A., Malykhin V.I., Sharifullin A.A., Feasibility evaluation of vacuum presence in a well annulus (In Russ.), Neftepromyslovoe delo, 2020, no. 1, pp. 60–64,

DOI: https://doi.org/10.30713/0207-2351-2020-1(613)-60-64

3. Isaev A.A., Takhautdinov R.Sh., Malykhin V.I., Sharifullin A.A., Development of the automated system for gas extraction from wells (In Russ.), Neft’. Gaz. Novatsii, 2017, no. 12, pp. 65–72.

4. Adonin A.N., Dobycha nefti shtangovymi nasosami (Oil production with rod pumps), Moscow: Nedra Publ., 1979, 213 p.

5. Sukhanov G.N., Ustanovlenie rezhima raboty skvazhiny, oborudovannoy shtangovoy glubinnonasosnoy ustanovkoy (Establishing the operating mode of a well equipped with a deep-rod pumping unit), Proceedings of USPTU, 1972, V. 8.

Currently Data Mining methods acquire popularity as a tool for analyzing volumetric information; such methods are based on both classical principles of exploratory data analysis and modern ones, including neural networks. Due to their high practical significance, Data Mining methods make it possible to compactly describe data, understand their structure, and classification, discover patterns in a chaos of random phenomena. The article is devoted to the issue of using detailed statistical analysis of some characteristics of directional wells for the purpose of predictive assessment of the oil potential of new wells or sidetracks. According to the authors, it is possible to increase the predictive potential of Data Mining methods only when the production characteristics of wells are predicted without using of production data, relying only on geological and technological parameters. The authors solve regression and classification problems at the intersection of exploratory data analysis and Data Mining methods, assess the forecasting accuracy of the algorithms used on several samples, and also demonstrate the statistically substantiated influence of geological and technological parameters on the production characteristics of wells. The performed studies confirm the adequate forecasting ability of geo-statistical models in conditions of data limitations. Working with categorized variables under the conditions of a classifier, an approach has been proposed that allows reducing significantly the probability of prediction error. Matrices of the influence of parameters that are valid for all directional wells of the object under consideration are derived. The importance and indispensability of data analysis technologies is indicated that allow obtaining data from 2D and 3D geological models, and, as a result, assessing the production potential and efficiency of well placement already at the modeling stage. Thus, it is proposed to introduce data analysis technologies into the field development process that are capable of describing volumetric data, identifying patterns, conducting classification and forecasting under conditions of uncertainty.

References

1. StatSoft.Ink, URL: https://www.statsoft.ru/home/textbook/default.htm

2. STATISTICA. Ofitsial’noe rukovodstvo (STATISTICA. Official Guide), Vol. 3, 2007.

3. 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.

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dannykh na komp’yutere: dlya professionalov (STATISTICA. The art of data
analysis on a computer: for professionals), St. Petersburg: Piter Publ., 2003,
688 p.

Improvement of the efficiency of the industrial safety management system for oil and gas facilities, in particular major pipeline transport objects, is one of the current issues solved by modern science. The article discusses the intermediate result of multi-year study carried out by the authors in the field of improving the accident forecasting system efficiency. During the study, the methodology for improving the efficiency of the system for forecasting the accident consequences at major pipeline objects was completed. The method of expert assessments, building of computer models using technologies of geoinformation system with the terrain relief taking into account, the main aspects of the methodology of the quality management system based on the process approach of the ISO 9000 series standards form the basis of the methodology. Individual fragments of the proposed changes are proven at the system departments of Transneft PJSC and implemented into the plans for the reconstruction and overhaul of facilities. Forecasts are embedded in documents in the field of industrial safety, including plans for the prevention, localization and elimination of oil and petroleum product spills. As a part of the ongoing developments, recommendations for site facilities were given as a separate element of possible forecasting systems. The system of forecasting the consequences of accidents at tank farms, proposed by the authors, which includes mathematical modeling and strength calculations, allows taking into account a greater number of factors. Testing of the methodology for predicting the consequences of accidents at tank farms was carried out within the framework of several research works, the results of which are taken as a principle into new design solutions of the sites. Statements for improving the system of forecasting the consequences of possible accidents are planned to be normatively fixed in the governing documents of the major pipeline system of oil and petroleum products.

References

1. Arkticheskiy shleyf. Chto potyanetsya za avariey pod Noril’skom (Arctic plume. What will happen after the accident near Norilsk),

URL: https://www.kommersant.ru/doc/4366214.

2. http://prosou.ru/viewtopic.php?t=599&ysclid=lvwdzij9wb596486997

3. https://tass.ru/proisshestviya/14010585?ysclid=lvwehvvabt441996811

4. Slepnev V.N., Maksimenko A.F., The basic principles of building a quality management system for prevention, localization and liquidation of effects of accidents at pipeline transport facilities (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2018, V. 8, no. 4, pp. 456–467, DOI: https://doi.org/10.28999/2541-9595-2018-8-4-456-467

5. Slepnev V.N., Maksimenko A.F., Organizing the quality management system for the processes of prevention, localization and elimination of accidents at pipeline transport facilities (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 2, pp. 106–111, DOI: https://doi.org/10.24887/0028-2448-2019-2-106-111

6. Slepnev V.N., Maksimenko A.F., Glebova E.V., Volokhina A.T., Methods of risk assessment in forecasting the consequences of accidents at pipeline transport facilities (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2020, V. 10,

no. 6, pp. 663–673, DOI: https://doi.org/10.28999/2541-9595-2020-10-6-663-673

7. Polovkov S.A., Gonchar A.E., Maksimenko A.F., Slepnev V.N., Assessment of the risk of damage to pipelines located in the arctic zone of the Russian Federation. Modeling of a spill and determination of the possible volume of oil taking surface topography into consideration (In Russ.), Territoriya Neftegaz, 2016, no. 12, pp. 88–93.

8. Polovkov S.A., Shestakov R.Yu., Aysmatullin I.R., Slepnev V.N., System conception in the development of measures on prevention and localization of accident consequences on oil pipelines in the arctic zone of Russian Federation (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2017, no. 1(28), pp. 20–29.

9. Polovkov S.A., Gonchar A.E., Pugacheva P.V., Slepnev V.N., Development of additional protecting constructions from oil spills based on three-dimensional digital modeling (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2018, V. 8, no. 2, pp. 197–205, DOI: https://doi.org/10.28999/2541-9595-2018-8-2-197-205

10. Aysmatullin I.R. et al., A systematic approach to protecting the Arctic from the effects of accidents on trunk pipelines (In Russ.), Neftegaz.Ru, 2018, no. 5, pp. 66–72.

11. Polovkov S.A., Gonchar A.E., Slepnev V.N., Maksimenko A.F., Modelling the consequences of possible accidents as a mechanism to improve the efficiency of planning and implementation of confinement and response operations (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 10, pp. 108–112,

DOI: https://doi.org/10.24887/0028-2448-2020-10-108-112