The article discusses issues of planning and conducting ice and metocean surveys in the license blocks located on the Arctic offshore. The major research objectives are described, followed by requirements to the expected results, as well as the main research directions and methods. The tasks of expeditionary ice and metocean surveys were determined both to provide meteo data for exploratory drilling stage, and also to provide design data for offshore oil and gas facilities for year-round operations in the freezing seas. Information on vessels and other technical means used during research is also presented. Unique experience of large-scale expeditionary research carried out by Rosneft Oil Company in the Barents, Kara, Laptev, East Siberian and Chukchi seas in 2012-2020 is described by the leading Russian scientific organizations that involved: Arctic and Antarctic Research Institute, Arctic Research Center and Far Eastern Federal University. The recommendations given in the article make it possible to optimize expeditionary and laboratory scope of work needed to study environmental conditions on the Arctic offshore. The obtained data can be used for design of infrastructure and exploration facilities, offshore production structures and hydrocarbon transportation in the arctic seas of the Russian continental shelf, as well as for marine logistics related to the transportation of hydrocarbons along the Northern Sea Route.

References

1. Pashali A.A., Kornishin K.A., Tarasov P.A. et al., Ice and hydrometeorological survey at Khatangskiy license block in the Laptev Sea (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2018, no. 3, pp. 22–27, DOI: 10.24887/0028-2448-2018-3-22-27.

2. Pavlov V.A., Kornishin K.A., Mironov E.U. et al., Peculiarities of consolidated layer growth of the Kara and Laptev Sea ice ridges (In Russ.),  Neftyanoe khozyaystvo = Oil Industry, 2016, no. 11, pp. 49–54.

3. Pavlov V.A., Kornishin K.A., Tarasov P.A. et al., Experience in Monitoring and Sizing Up of Icebergs and Ice Features in the South-Western Part of Kara Sea During 2012-2017 (In Russ.),  Neftyanoe khozyaystvo = Oil Industry, 2018, no. 12, pp. 82–87, DOI: 10.24887/0028-2448-2018-12-82-87.

4.  Pashali A.A., Kornishin K.A., Tarasov P.A., Efimov Ya.O., Nesterov A.V., Chernov A.V., Buzin I.V., Svistunov I.A., Maksimova P.V., Iceberg towing as a technology for its drift change to ensure safe Arctic development (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2018, no. 11, pp. 36-40, DOI: 10.24887/0028-2448-2018-11-36-40.

5. Pashali A.A., Kornishin K.A., Tarasov P.A. et al., Special aspects of ice strength seasonal variability in Russian Arctic (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 11, pp. 51–56, DOI: 10.24887/0028-2448-2020-11-51-55.

6. Pashali A.A., Kornishin K.A., Efimov Ya.O. et al., Seasonal variability of strength properties of ice formations on the Russian continental shelf (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 8, pp. 63–67, DOI: 10.24887/0028-2448-2021-8-63-67.

7. Sochnev O.Ya., Kornishin K.A., Tarasov P.A. et al., Studies of glaciers in the Russian Arctic for safe marine operations in iceberg waters (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2018, no. 10, pp. 92–97,  DOI: 10.24887/0028-2448-2018-10-92-97.

8. Kornishin K.A., Tarasov P.A., Efimov Ya.O. et al., Development of corporative Ice Management System for Arctic license blocks (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2017, no. 11, pp. 48-51, DOI: 10.24887/0028-2448-2017-11-48-51.

9. Sochnev O.Ya., Kornishin K.A., Tarasov P.A. et al., Special aspects of iceberg towing in early ice conditions for arctic shelf development (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 10, pp. 78–81, DOI: 10.24887/0028-2448-2019-10-78-81.

The main issue of the article is the assessment of an economic effect from the use of the Information System (IS), developed by Rosneft Oil Company for Arctic offshore projects. Most of the Rosneft’ Arctic offshore license
blocks are the areas with a high level iceberg hazard. It requires the permanent monitoring of the ice conditions around the “working point” (drilling, undersea pipe laying, subsea production complex installation etc.) both with the establishing of constant readiness for possible threats response. Exact estimation of ice threats together with well-timed and well-judged actions eliminating them, allow to avoid unjustified brakes of work, to reduce drilling rig and support vessels idle time and as the result to reduce or even to avoid the financial losses caused by the abovementioned reasons. The Rosneft experience in Arctic offshore drilling enlightened the desperate need in exact ice threat detection and correct estimation of the threat level refer to current working drilling operations. IS was created to meet these requirements. This information system is intended for monitoring ice and  hydrometeorological conditions, for there changes forecasts developing, timely detection of all  potentially dangerous ice formations (icebergs and bergy bits) and arranging of effective physical impact on these objects (usually towing) for changing of their drifts trajectories. The functions implemented in the IS allow to integrate data obtained from various sources (satellite images, aeronautical reconnaissance data, weather station data, hydrometeorological forecasts, etc.), and to perform an estimation of ice threats, as well as calculate the recommended trajectory and towing mode of ice formations. IS use in Rosneft offshore projects allow to increase the safety of exploration work in areas with high iceberg hazard, as well as to reduce significantly rigs and vessels possible downtime due to ice threats.

The article has been prepared by specialists from Rosneft Oil Company and the Reservoir and Petroleum Engineering Department of RN-Shelf-Arctic LLC, a subsidiary of Rosneft which carries out geological research and hydrocarbon exploration within the Rosneft’s license blocks upon the Arctic and Far Eastern shelves of the Russian Federation. The article provides an overview of structure and depositional environments of the Permian clastic deposits within the marine extension of the Kolvinsky megaswell. There are large oil fields (Vozeiskoye, Kharyaginskoye, Yuzhno-Khylchuyuskoye) within onshore part of this vast area of oil and gas accumulation. These fields have wide stratigraphic range of oil-bearing capacity from the Lower Devonian to the Triassic. The importanсе of this research is associated with the proven petroleum potential of the Permian deposits within Timan-Pechora petroleum basin. Generalization of the previous results and comprehension with new detailed 3D seismic interpretation allowed the authors to: 1) detail the geological structure and depositional environments of the Permian clastic deposits; 2) identify and map the most perspective deposits that can be considered as a potential hydrocarbon reservoir; 3) reduce geological uncertainties associated with the presence and quality of the Permian clastic reservoir. The article is based on the results of interpretation of 3D and 2D seismic data, geological and geophysical data of adjacent areas, as well as regional geology of the Pechora Sea.

References

1. Atlas neftegazonosnosti i perspektiv osvoeniya zapasov i resursov uglevodorodnogo syr'ya Nenetskogo avtonomnogo okruga (Atlas of oil and gas content and prospects for the development of reserves and resources of hydrocarbon raw materials of the Nenets Autonomous District), Nar'yan-Mar: Publ. of GUP NAO NIATs, 2004, 115 p.

2. Kalamkarov L.V., Neftegazonosnye provintsii Rossii i sopredel'nykh stran (Oil and gas provinces of Russia and neighboring countries), Moscow: Neft' i gaz Publ., 2005, 570 p.

3. Malysheva E.O., Larionova Z.V., Ryabinkina N.N., Timonina N.N., Prirodnye rezervuary v terrigennykh formatsiyakh Pechorskogo neftegazonosnogo basseyna (Natural reservoirs in terrigenous formations of the Pechora oil and gas basin), Syktyvkar: Publ. of Komi Scientific Center of the Ural Branch of the Russian Academy of Sciences, 1993, 154 p.

4. Teplov E.L., P.K. Kostygova, Larionova Z.V. et al., Prirodnye rezervuary neftegazonosnykh kompleksov Timano-Pechorskoy provintsii (Natural reservoirs of oil and gas bearing complexes of the Timan-Pechora province), St. Petersburg, Renome Publ., 2011, 286 p.

5. Larionova Z.V., Bogatskiy V.I., Dovzhikova E.G. et al., Timano-Pechorskiy sedimentatsionnyy basseyn (Atlas geologicheskikh kart i ob"yasnitel'naya zapiska) (Timan-Pechora sedimentary basin (Atlas of geological maps and explanatory note)), Ukhta: Publ. of TP NITs, 2000, 122 p.

6. Grunis E.B., Marakova I.A., Rostovshchikov V.B., Structural features and formation conditions of the Permian terrigenous sequence and stages of non-anticlinal trap formation in the northeastern part of the Timan-Pechora Province (In Russ.), Geologiya nefti i gaza, 2017, no. 1, pp. 13–25.

Rosneft Oil Company focuses on research work at the West Siberian basin. The territories are characterized by a low hydrocarbon potential, but they are of interest to the company in the future. Such territories include the peripheral regions of the basin, where the main problem for the Jurassic reservoirs is the forecast of their phase saturation. This problem does not allow the company to actively invest in prospecting and exploration work in such areas. In order that, Rosneft Oil Company to be able to increase the company's hydrocarbon resource base by opening new hydrocarbon deposits in the peripheral regions of the West Siberian basin, it is necessary to understand the mechanism of formation of deposits of different phase composition. For example, small Yuzhno-Venikhyartskoye gas-condensate field was discovered in 2014 on the border of the northern districts of the Uvat region and Khanty-Mansiysk autonomous district. The phase composition of hydrocarbons is uncharacteristic for territories where oil deposits are usually discovered.

The article considers the results of the studying the nature of the formation of gas-condensates in the peripheral territories of West Siberian basin on the example of Yuzhno-Venikhyartskoye gas-condensate field. The authors briefly describe geological, geodynamic, geochemical, thermobaric and tectonic conditions that are necessary for the formation and existence of gas-condensate deposits at depths of up to 2 km in the peripheral territories of the West Siberian basin. There is no doubt that understanding the formation mechanism of gas-condensate deposits in the peripheral territories of sedimentary basins will allow the company to expand its prospects for prospecting not only in the northern part of the Uvat region, but also in the southern regions of the Khanty-Mansiysk autonomous district.

1. Elisheva O.V., Lazar' E.L., Lyzhin E.A. et al., The methodology of adaptation for searching new hydrocarbon reservoir in the Jurassicand Neokomian sediments of the Uvat project areas by the results of the exploration 2015–2019 (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 12, pp. 2–7, DOI: 10.24887/0028-2448-2020-11-32-37

2. Tissot B.P., Welte D.H., Petroleum formation and occurrence, Springer-Verlag Telos, 1984, 699 p.

3. Kontorovich A.E., Ocherki teorii naftidogeneza (Essays on the theory of naphthydogenesis), Novosibirsk: Publ. of SB RAS, 2004, 545 p.

4. Lyugay D.V., Lapshin V.I., Volkov A.N. et al., Features of the composition, properties and phase characteristics of reservoir mixtures of deep-seated deposits of oil and gas condensate fields of Gazprom PJSC (In Russ.), Vesti gazovoy nauki, 2015, no. 4(24), pp. 74–83.

5. Lapshin V.I. et al., Features of the phase behavior of reservoir gas condensate systems in the field of direct evaporation (In Russ.), Vesti gazovoy nauki, 2016, no. 2(26), pp. 131–137.

6. Zhuze N.G., Residual saturation of Neocomian deposits in the north of Western Siberia - an additional source of hydrocarbons (In Russ.), Geologiya nefti i gaza, 1989, no. 11, pp. 8-14.

7. Taranenko E.I., Gerasimov Yu.A. et al., The problem of gas condensate systems formation (In Russ.), Vestnik RUDN. Seriya: Inzhenernye issledovaniya, 2008, no. 1, pp. 96–104.

8. Bazhenova O.K., Rannyaya generatsiya nefti i perspektivy neftenosnosti nebol'shikh glubin (Early oil generation and shallow oil-bearing prospects), Geoinformak’s Review: Geologiya, metody poiskov, razvedki i otsenki mestorozhdeniy toplivno-energeticheskogo syr'ya (Geology, methods of prospecting, exploration and evaluation of deposits of fuel and energy raw materials), 1992, V. 6, pp. 50–52.

9.  Stroganov L.V., Skorobogatov V.A., Gazy i nefti ranney generatsii Zapadnoy Sibiri (Earlier generation gas and oil of Western Siberia), Moscow: Nedra Publ., 2004, 415 p.

10. Bylinkin G.P., Evaluation of phase transition of deep-buried formation fluids (In Russ.), Geologiya nefti i gaza, 2006, no. 2, pp. 55–63.

11. Neruchev S.G., Nefteproizvodyashchie svity i migratsiya nefti (Oil producing formations and oil migration), Leningrad: Nedra Publ., 1969, 240 p.

12. Vassoevich N.B., The theory of sedimentary-migration origin of oil (historical overview and current state) (In Russ.), Izvestiya AN SSSR. Ser. Geologiya, 1967, no. 11, pp. 135-156.

13. Lopatin N.V., Historical and genetic analysis of oil generation using the model of uniform continuous lowering of the source reservoir (In Russ.), Izvestiya AN SSSR. Ser. Geologiya, 1976, no. 8, pp. 93-101.

14. Volkov A.N. et al., Behavior of geochemical factors in context of low reservoir pressures at development of deposits (In Russ.), Vesti gazovoy nauki, 2016, no. 2(26), pp. 28–33.

15.  Zor'kin L.M., Genezis gazov podzemnoy gidrosfery (v svyazi s razrabotkoy metodov poiska zalezhey uglevodorodov) (The underground hydrosphere gases genesis (in connection with the development of methods for the search for hydrocarbon deposits)), URL: http://www.geosys.ru/images/articles/Zorkin_1_2008.pdf.

16. Goncharov I.V., Geokhimiya neftey Zapadnoy Sibiri (Geochemistry of oil in Western Siberia), Moscow: Nedra Publ., 1987, 181 p.

17. Starobinets I.S., Geologo-geokhimicheskie osobennosti gazokondensatov (Geological and geochemical features of gas condensates), Leningrad: Nedra Publ., 1974, 151 p.

The main purpose of geologists and geophysicists work is creation of a reliable consistent geological model of a target area. At the same time, one of the main problems is the reliability of seismic predictions of reservoir parameters in complex reservoirs. The article discusses the features of predicting effective thicknesses from seismic data for the deposits of the Ju₂ formation of the Tyumen suite in case of the group of fields in the Tortasinsky block. The upper part of Tyumen suite is productive almost for all deposits of Khanty-Mansiysk Autonomous District. Deposits of Ju₂ strata were formed in transitional depositional environment of a coastal plain. Distinguishing features of Middle Jurassic deposits are: laterally poorly continuous shale barriers, high heterogeneity, low thickness of sandy-silty layers (close to seismic resolution), laterally abrupt sandstone facies replacement with mudstone and siltstone, presence of carbon-bearing interlayers - all of these form a complex structure of a predicted interval. Therefore, facies analysis is one of the most important tools for oil and gas reservoir study. The use of multi-scale geological and geophysical information including 3D seismic data enable interpreters to perform lateral wave pattern variation analysis and based on it identify the main facies, specified their internal structure and formation features.

Based on results obtained by specialists of Tyumen Petroleum Research Center, Sorovskneft and Rosneft it is shown that dividing of a study area into facies zones gives opportunity to improve prediction accuracy of effective thickness based on seismic attributes. The outcome of this work allow to specify hydrocarbon prospects of Ju₂ strata deposits of Tyumen suite in Tortasinsky license areas of Rosneft Oil Company. 

References

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

2. Gayfulina E.F., Nadezhnitsskaya N.V., Belousov S.L. et al., Comprehensive analysis of geological and geophysical information for the facies depositional environment prediction of Ju2 strata of Tyumen suite (In Russ.), Izvestiya vuzov. Neft' i gaz, 2020, no. 6, pp. 25–39.

3. Kornev V.A., Prognozirovanie ob"ektov dlya poiskov zalezhey uglevodorodnogo syr'ya po seysmogeologicheskim dannym (Forecasting objects for prospecting for hydrocarbon deposits based on seismic and geological data), Tyumen: Publ. of Tyumen State Oil and Gas University, 2000, 374 p.

4. Nezhdanov A.A., Geologicheskaya interpretatsiya seysmorazvedochnykh dannykh (Geological interpretation of seismic data), Tyumen: Publ. of Tyumen State Oil and Gas University, 2000, 133 p.

5. Bilibin S.I., Perepechkin M.V., Yukanova E.A., Geological modelling while insufficient data availability using DV-Geo software package (In Russ.), Geofizika, 2007, no. 4, pp. 191–194.

6. Kavun M.M., Stepanov A.V., Stavinski P.V., Forecasting effective reservoir thickness within interwell space: General approach, trends and data apprisal (In Russ.), Geofizika, 2008, no. 4, pp. 17–21.

The article describes the main principles of estimating volumetric parameters of gas onshore deposits in low-permeable reservoirs of the Turonian stage that were formed as a result of long-term study of "over-Cenomanian" deposits at the fields of Rosneft Oil Company, in particular, at the largest Kharampurskoye oil and gas condensate field. Based on a detailed analysis of the section, the authors formulated recommendations for optimal logging suite, well testing and analysis of core taken from highly swellable clay rocks of the Kuznetsovskaya suite, as well as for complex interpretation of geological and geophysical data for estimating gas reserves in unconventional reservoirs that were previously considered as substandard. The authors substantiated an optimal development strategy and technology for low-permeable gas reservoirs of the Turonian age based on the cycle of conceptual design of infrastructure, geomechanical and dynamic modeling of the reservoir, taking into account the economic efficiency at each stage of the work. Recommendations for drilling and research work have also been substantiated. Based on the results of the study of the Kharampurskoye field, a special methodology for the development design and assessment of volumetric parameters of dry gas in the Turonian deposits makes it possible to increase the reliability of the obtained geological and petrophysical information, and to calculate initial gas in-place with a higher degree of accuracy. This, in turn, will make it possible to correctly substantiate an economically efficient strategy for the development of low-permeable Turonian gas deposits, as well as reduce technological and economic risks. And the proposed approaches to the development of a specific target will involve prospective areas of the Turonian gas deposits in Western Siberia into development.

References

1. Kiselev A.N., Oshnyakov I.O., Melikov R.F. et al., Aspects of the development of low-permeability gas reservoirs of Turonian age (In Russ.), SPE-191653-18RPTC-RU, 2018, DOI: https://doi.org/10.2118/191653-18RPTC-MS

2. Kudamanov A.I., Agalakov S.E., Marinov V.A., The problems of Turonian-early Coniacian sedimentation within the boundaries of the West Siberian plate (In Russ.), Geologiya, geofizika i razrabotka neftyanykh i gazovykh mestorozhdeniy, 2018, no. 7, pp. 19-26.

3. Popov A.P., Russian companies are ready to produce Turonian gas (In Russ.), Neftegazovaya vertikal', 2018, no. 2, pp. 59-62.

4. Mal'shakov A.V., Oshnyakov I.O., Kuznetsov E.G. et al., Innovative approaches to study heterogeneous anisotropic reservoirs of Turonian deposits for reliable assessment of reservoir properties (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2016, no. 11, pp. 18–22.

5. Mal'shakov A.V., Oshnyakov I.O., Zhadeeva E.A. et al., Justification of microlayered Turonian age deposits petrophysical model for reliable reservoir properties assessment (In Russ.), SPE-182501-RU, 2016, DOI: https://doi.org/10.2118/182501-RU.

6. Agalakov S.E., Kudmanov A.I., Marinov V.A., Facies model of the Western Siberia Upper Cretaceous (In Russ.), Interekspo GEO-Sibir', 2017, V. 2, no. 1, pp. 101-105.

7. Metodicheskie rekomendatsii po podschetu zapasov nefti i gaza ob’emnym metodom. Otsenka kharaktera nasyshchennosti po dannym GIS (Guidelines for the calculation of reserves of oil and gas by volumetric method. Assessment of the nature of saturation according to well logging): edited by Petersil’e V.I., Poroskun V.I., Yatsenko G.G., Moscow – Tver: Publ. of VNIGNI, 2003, 261 p.

8. Kiselev A.N., Buchinskiy S.V., Yushkov A.Yu. et al., Pilot development of Turonian low-permeability gas reservoirs of the Kharampurskoye field (In Russ.), Vestnik OAO “NK “Rosneft”, 2015, no. 3, pp. 46-49.

9. Khakimov A.A., Kholkina Yu.D., Loznyuk O.A. et al., Improving the quality of predicted technological parameters of development by using integrated approach to modeling (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 9, pp.82-85, DOI: 10.24887/0028-2448-2021-9-82-85

10. Loznyuk O.A., Surtaev V.N., Sakhan' A.V. et al., A multistage stimulation operation to unlock the gas potential of the Turonian siltstone formation in Western Siberia (In Russ.), SPE-176706-RU, 2015, DOI: https://doi.org/10.2118/176706-MS

Modern well-testing equipment allows to record changing of bottomhole pressure with a resolution of 1 per second and sensibility less than 0.0001 MPa. The definition of gauges, using for recording a build-up curve, gives to modern engineers an opportunity of identification such a difficult filtration models as dual porosity, linear/radial composite and so on. However, along with increasing accuracy of high-sensitive gauges (strain gauges of quartz or sapphire type) records of build-ups there is an appearance of derivative bottomhole pressure noisiness. And a final interpretation of well-tests depends on quality of a derivative. Currently available noise reduction tools are based on linear or logarithmic filtering. The basic principle of the filtering is excepting current amount of pressure points of each logarithmic cycle. That method could be called a necessary measure, because excepting a part of records leads to a simplification of real difficult dinamics, and the real case could have some artifacts. There are no points of view in domestic and foreign literature, covering such issues as a nature of noisiness and its correlations with different technological factors. The understanding of these issues will make us able to adjust well testing and make some technical preparations even at a planning stage.

This paper is considering depression drainage mode influence on noisiness of derivatives. According to the authors, it is possible to decrease negative effects using some methods, consisting of the right choice of depression mode before a pressure transient test.

References

1.  Houzé O., Viturat D., Fjaere O.S., The theory and practice of pressure transient and production analysis & The use of data from permanent downhole gauges, URL: https://www.kappaeng.com/documents/flip/dda51001/files/assets/basic-html/page-1.html

2. Deeva T.A., Kamartdinov M.R., Kulagina T.E., Mangazeev P.V., Gidrodinamicheskie issledovaniya skvazhin: analiz i interpretatsiya da

nnykh (Well test: analysis and interpretation of data), Tomsk: Publ. of TPU, 2009, 243 p.

In conditions of deterioration of the reservoir properties of potential oil and gas bearing areas on mature and green fields, engineers are continuously searching and developing effective well completion technologies to maintain and increase oil production levels. Based on successful international experience, Russian oil and gas companies use horizontal wells (HW) with multi-stage hydraulic fracturing (MSHF) for the cost-effective development of low-permeable reservoirs. In searching for the best technologies and engineering solutions, the companies tested different lengths of horizontal section of HW, the number of hydraulic fracturing (HF) stages and distances between hydraulic fracturing ports, as well as different specific mass of the proppant per frac port. At the same time, publications practically do not describe systemic approaches to assessing the actual technological efficiency of HW with MSHF and the viability of increasing the technological complexity of horizontal well completion technologies.

The aim of this work was to develop the methodical recommendations for analyzing the actual ratio of performance indicators of HW with MSHF of various designs (different lengths of horizontal section of HW and the number of HF stages) compared with directional wells (DW) with single HF. Developing the methodical recommendations for analyzing we discovered the typical methodological errors and developed the methodology for analysis of the actual ratio of indicators of wells of various designs, in particular, HW with MSHF relative to DW with HF. The discussed methodological recommendations and automated forms of the actual multiplicity of performance indicators analysis of HW with MSHF and DW with HF have been tested at key fields of Rosneft Oil Company.

References

1. Galeev R.R., Zorin A.M., Kolonskikh A.V. et al., Optimal waterflood pattern selection with use of multiple fractured horizontal wells for development of the low-permeability formations (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2013, no. 10, pp. 62–65.

2. Gilaev G.G., Afanas'ev I.S., Timonov A.V.,  Priobskoe oilfield pilot area (In Russ.), Nauchno-tekhnicheskiy vestnik OAO “NK “Rosneft'”, 2012, no. 2, pp. 22–26.

3. Zorin A.M., Usmanov T.S., Kolonskikh A.V. Et al., Operational efficiency improvement in horizontal wells though optimizing the design of multistage hydraulic fracturing at Priobskoye Northern territory (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2017, no. 11, pp. 122–125, DOI: 10.24887/0028-2448-2017-12-122-125

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

5. Mulyak V.V., Chertenkov M.V., Shamsuarov A.A. et al., Increasing efficiency of hard-to-recover reserves involving in the development with use of multi-zone hydraulic fracturings in horizontal wells (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2011, no. 11, pp. 48–51.

6. Rodionova I.I., Shabalin M.A., Mironenko A.A., Khabibullin G.I., Field development plan and well completion system optimization for ultra-tight and ultra-heterogeneous oil reservoirs (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 10, pp. 72-76, DOI: 10.24887/0028-2448-2019-10-72-76

7. Sitnikov A., Asmandiyarov R., Pustovskikh A. et al., Benchmarking of various types of completions and MS technologies for horizontal wells at the Priobskoe field southern license topic (In Russ.), SPE-187771-RU, 2017, https://doi.org/10.2118/187771-MS

8. Fedorov A.E., Dil'mukhametov I.R., Povalyaev A.A. et al., Multivariate optimization of the development systems for low–permeability reservoirs of oil fields of the Achimov formation  (In Russ.), SPE-201811-RU, 2020, https://doi.org/10.2118/201811-MS

9. Cherevko M.A., Optimizatsiya sistemy gorizontal'nykh skvazhin i treshchin pri razrabotke ul'tranizkopronitsaemykh kollektorov (Optimization of a system of horizontal wells and fractures in the development of ultra-low-permeability reservoirs): thesis of candidate of technical science, Tyumen, 2015.

10. Cherevko M.A., Yanin K.E., The first results of the application of multi-stage hydraulic fracturing in horizontal wells Priobskoye field (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2015, no. 2, pp. 74–77.

11. Shabalin M., Khabibullin G., Suleymanov E. et al., Tight oil development in RN-Yuganskneftegas (In Russ.), SPE-196753-MS, 2019, https://doi.org/10.2118/196753-MS

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

13. Butler R.M., Horizontal wells for the recovery of oil, gas and bitumen, Petroleum Society of CIM, Monograph no. 2, 1994.

Analysis of Rosneft's mechanized well stock has shown that the main causes of failures of electric submersible pump (ESP) units are mechanical impurities, salt deposits and corrosion. Average mean time between failures of the equipment depends not only on well conditions, but also on the design of the pump, materials used for ESP stages, as well as the construction of ESP stages themselves. However, the essential difference of the data about the reasons of failures and operating conditions does not allow to provide the accurate analysis of the influence of the design of the pumps and the materials used on the ESP performance up to failure. In order to clarify the influence of negative factors on the ESP performance, a methodology and stands for comprehensive comparative testing of ESP units were developed within the framework of a targeted innovative project. The test results allow us to answer the questions about the applicability of ESP assembly materials and designs for operation in different field conditions with due regard to the complicating factors. The main statements of the methods are presented, including the methods of determining partial and integral equipment quality indices; the construction schemes of stands for hydrodynamic and endurance tests of ESP components and parts are shown. The results of the bench tests became the basis to draw conclusions about the construction of ESP stages and bearings preferable for working in the wells in the presence of complicating factors. The results of the bench tests have already started to be used to select the optimal ESP unit in terms of design and materials and will also be used for creating a new version of Rosneft's uniform technical requirements, which will further increase the efficiency of oil production with the use of ESP.

References

1. Yakimov S.B., Shportko A.A., Sabirov A.A., Bulat A.V., The influence of concentration of abrasive particles in the produced fluid to the reliability of electric centrifugal submersible pumps (In Russ.), Territoriya “NEFTEGAZ” = Oil and Gas Territory, 2017, no. 6, pp. 50–56.

2. Dolov T.R., Donskoy Yu.A., Ivanovskiy A.V. et al., To the question of the characteristics dependence of vane pumps stages on the test conditions (In Russ.), Oborudovanie i tekhnologii dlya neftegazovogo kompleksa, 2020, no. 2 (116), pp. 23–26, DOI: 10.33285/1999-6934-2020-2(116)-23-26

3. Ivanovskiy V.N., Sabirov A.A., Dolov T.R. et al., Methods and stands for testing stages of electric driven vane pumps. Main test results (In Russ.), Territoriya “NEFTEGAZ” = Oil and Gas Territory, 2020, no. 7-8, pp. 26–33.

Hydrogen sulfide and mercaptans dissolved in oil have a negative impact on the rate of corrosion of metal equipment of refineries. The content of hydrogen sulfide in oil is regulated limited. According to the Technical Regulation of the Eurasian Economic Union 045/2017, the content of hydrogen sulfide in oil allowed for circulation should be reduced from 100 to 20 ppm. This tightening requires oil producers to strengthen measures to reduce the background value of hydrogen sulfide, including a significant increase in the use of specific chemical absorbers (H2S - scavengers, most of which are formaldehyde or triazine based compounds.) A negative aspect of the use of H2S-scavengers is the formation of solid polymethylene sulfides - as reaction products, which are subsequently deposited in the equipment of primary oil distillation. Isolated pockets of corrosion develop under the deposits, in addition, the sections of pipe sections are blocked and the drainage lines of separators are clogged, which in turn causes unscheduled stops, repairs and deterioration of the technical and economic indicators of enterprises. The use of other methods of protection against hydrogen sulfide is accompanied by significantly higher costs.

In order to assess the validity of the regulated values of hydrogen sulfide content in oil, Rosneft Oil Company has initiated research aimed at studying the effect of hydrogen sulfide in oil on refining processes, including product quality and corrosion processes. The article presents the results of the first series of laboratory and field experiments. The most large-scale experiment was the organization of the run of oil with an increased content of hydrogen sulfide without the preliminary introduction of H2S-scavengers to two refineries of Rosneft Oil Company. The result indicates that there are no deviations in the key processes of oil refining with a hydrogen sulfide content of up to 80-90 ppm.

References

1. Leont'eva S.A., Podlesnova E.V., Botin A.A. et al., Determination of 1,2,4-trithiolane in oil and petroleum products by gas chromatography (In Russ.), Zhurnal analiticheskoy khimii = Journal of Analytical Chemistry, 2019, V. 74, no. 12, pp. 930-933.

2. Ishmiyarov E.R., Reagenty dlya neftepromyslovoy khimii (neytralizatory serovodoroda, ingibitory soleotlozheniya i bakteritsidy) na osnove poluatsetaley formal'degida (Reagents for oilfield chemistry (hydrogen sulfide neutralizers, scale inhibitors and bactericides) based on formaldehyde hemiacetals): thesis of candidate of chemical science, Ufa, 2016.

The article addresses various aspects of companies digitalization with respect to the regulatory documents of the Russian Federation and as applied to major companies program documents. The authors make the point that at present, in spite of the numerous documents, there is no generally accepted concept of digitalization or of its components; each company has its own understanding of the term. At the same time, the major companies realize that digitalization must not be carried out for its own sake. Digitalization is the tool for improving business performance. The article describes the evolution of the concept ‘digital twin’. It points out that a number of data resources can be used for entering data into the digital twin, e.g., the theoretical background, real data from the facility obtained by means of physical sensors, or from virtual analyzers, external ports, and other sources. Because the digital twin is used for predicting the facility operation in various conditions to optimize the real facility, then, eventually, carrying out virtual testing instead of real testing should result in more effective processes. A digital company or a digital factory in particular is not a three-dimensional model with excessive data, but a set of interrelated digital initiatives in which each of the initiatives improves business performance. The authors offer an explanation why it is only by gradual preparation of the company for digital transformation and by systematic implementation of the digitalization road map that real results can be achieved. The authors give examples of the various ways of applying predictive analytics to gradual digitalization of production, as well as examples of incorporating virtual/augmented reality into training courses that employ models based on digital twin.

References

1. Tao F. et al., Digital twin in industry: State-of-the-art, IEEE Transactions on Industrial Informatics, 2018, V. 15, no. 4, pp. 2405–2415, DOI:10.1109/TII.2018.2873186

2. Borovkov A.I. et al., Digital twins and digital transformation of defense industry enterprises (In Russ.), Vestnik Vostochno-Sibirskoy otkrytoy akademii, 2019, V. 32.

3. Ponomarev K.S., Feofanov A.N., Grishina T.G., Enterprise digital twin - instrument of digitalization the activity of the organization (In Russ.), Avtomatizatsiya i modelirovanie v proektirovanii i upravlenii, 2019, no. 2(4), DOI: 10.30987/article_5cf2d1c56f8944.09486334

4. Danilov-Danil'yan V.I., Ecology, hydrology, digitalization, digital twins and the elementary truths of modeling methodology (In Russ.), Collected “Nauchnye problemy ozdorovleniya rossiyskikh rek i puti ikh resheniya” (Scientific problems of rehabilitation of Russian rivers and ways to solve them), 2019, pp. 497–502.

5. Kulagin V., Sukharevski A., Meffert Yu., Nastol'naya kniga po tsifrovizatsii biznesa (Business digitalization handbook), Moscow: Intellektual'naya Literatura Publ., 2019, 293 p.

6. Khaimovich I.N., Ramzaev V.M., Razrabotka modeli dannykh dlya funktsionirovaniya proizvodstvennykh aktivnykh elementov na osnove informatsionnogo vzaimodeystviya (Development of data model for production active elements functioning on the basis of information interaction), IV International conference and youth school “Informatsionnye tekhnologii i nanotekhnologii” (Information technology and nanotechnology), 2018, pp. 2149-2158.

7. Pavlov V.A. et al., Prospects for applying virtual simulators to hazardous production (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 11, pp. 70–72, DOI: 10.24887/0028-2448-2020-11-70-72

The geology paradigm plays a very important role in geological exploration of a petroleum sedimentary basin or sedimentary complex. Paradigm changing or adjusting leads to a new level of exploration and discovery of new hydrocarbon deposits. The Upper Devonian sedimentary complex has important structure-forming significance for overlying deposits of Carboniferous and Permian in the Volga-Ural petroleum province. It contains numerous open oil deposits and has significant resource potential. Main attention was paid for a long time to the barrier arch-shaped rises framed the Kama-Kinel depressions, since the largest oil traps and oil deposits are confined to them. At the same time, the internal structure of the Upper Devonian deposits has a much more complex structure than is generally believed. The Famenian rimmed carbonate platforms are the resulting morphological forms of Late Devonian sedimentation in Volga-Ural paleobasin. Sedimentary carbonate bodies of a smaller scale stand out inside them. The traditional bed approach leads to underestimation and loss of potential oil reservoirs and significantly narrows the field of the geology exploration. Understanding of morphology features of multi-scale carbonate bodies of Frasnian and Famenian has important practical value as directly influences the strategy of exploration works within license areas and geological interpretation of the 3D seismic.

References

1. Fortunatova N.K., Zaytseva E.L., Bushueva M.A. et al., Verkhniy devon Volgo-Ural'skogo subregiona: materialy po aktualizatsii stratigraficheskikh skhem (Upper Devonian of the Volga-Ural subregion: materials for updating stratigraphic), Moscow: Publ. of VNIGNI, 2015, 176 p.

2. Mirchink M.F., Khachatryan R.O., Gromeka V.I. et al., Tektonika i zony neftegazonakopleniya Kamsko-Kinel'skoy sistemy progibov (Tectonics and oil and gas accumulation zones of the Kama-Kinel system of troughs), Moscow: Nedra Publ., 1965, 214 p.

3. Shcherbakov O.A., Pakhomov I.V., Sharonov L.V. et al., Paleotectonics and facies of the Late Devonian and Early Carboniferous of the western slope of the Middle and South Urals and Urals (In Russ.), Litologiya i poleznye iskopaemye, 1966, no. 2, pp. 87–98.

4. Atlas neftyanykh i neftegazovykh mestorozhdeniy gruppy “LUKOYL-PERM''” (Atlas of oil and oil and gas fields of the LUKOIL-PERM group): edited by Tret'yakov O.V., Perm: Aster Plyus Publ., 2017, 160 p.

5. Lozin E.V., Atlas neftyanykh i gazovykh mestorozhdeniy, razrabatyvaemykh PAO ANK “Bashneft'” (Atlas of oil and gas fields developed by Bashneft PJSC), Ufa: Publ. of BashNIPIneft', 2015, 270 p.

6. Riding R., Structure and composition of organic reefs and carbonate mud mounds: concepts and categories, Earth-Science Reviews, 2002, V. 58, pp. 163–231, DOI:10.1016/S0012-8252(01)00089-7.

7. Shakirov V.A., Nikitin Yu.I., Vilesov A.P. et al., A new direction of exploration of oil deposits on the Bobrovsko-Pokrovsky arch (Orenburg region) (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2016, no. 12, pp. 90–94.

8. Vilesov A.P., Nikitin Yu.I., Akhtyamova I.R., Shirokovskikh O.A., The Frasnian reefs of the Rybkinsky group: facial structure, formation stages, oil potential (In Russ.), Geologiya, geofizika i razrabotka neftyanykh i gazovykh mestorozhdeniy, 2019, no. 7, pp. 4–22, DOI: 10.30713/2413-5011-2019-7(331)-4-22

9. Vilesov A.P., Boyarshinova M.G., Vinokurova E.E., Znachenie stromatolitov v formirovanii karkasa famenskikh rifov Volgo-Ural'skoy neftegazonosnoy provintsii (Role of stromatolites in Famenian reef framework formation of Volga-Ural oil-and-gas-bearing Province), Collected papers “Geologiya rifov” (Geology of reefs), Proceedings of Vserossiyskogo litologicheskogo soveshchaniya, Syktyvkar: Publ. of Institute of Geology of the Komi Science Center of the Ural Branch of the Russian Academy of Sciences, 2015, pp. 27–29.

10. Vilesov A.P., A model of the carbonate thickness sedimentation of the Famennian stage of Bobrovsko-Pokrovsky swell (Volgo-Ural oil and gas province) (In Russ.) Geologiya, geofizika i razrabotka neftyanykh i gazovykh mestorozhdeniy, 2017, no. 6, pp. 4-12.

11. Gritchina V.V., Prospecting works on reef deposits using the example of Yuzhno-Orlovskoye oil field (In Russ.), Nauchno-tekhnicheskiy vestnik OAO “NK “Rosneft'”, 2013, no. 3, pp. 3–7.

12. Neganov V.M., Shumilov A.V., Cherepanov S.S., Shumskiy I.F., Major discovery of perm region geophysics and oilers in early XXI century (In Russ.), Geofizika, 2013, no. 5, pp. 26–31.

13. Nefedov N.V., Karpov V.B., Aref'ev Yu.M. et al., Geological structure features of Menzelinsky, Timerovsky and Olginsky fields of the Republic of Tatarstan as a result of their genetic nature (In Russ.), Georesursy = Georesources, 2018, V. 20(2), pp. 88–101.

14. Stashkova E.K., Belyaeva N.V., Geological modeling, reservoirs and development sequence on the example of one of the fields in the Perm territory (In Russ.), Geologiya, geofizika i razrabotka neftyanykh i gazovykh mestorozhdeniy, 2007, no. 7, pp. 51–56.

15. Vilesov A.P., Pyatunina E.V., Chudinov Yu.V., Opyt kompleksirovaniya sovremennykh geologo-geofizicheskikh metodov issledovaniya verkhnedevonskikh rifov pri poiskovom burenii v severnykh rayonakh Permskogo Kraya (The experience of integrating modern geological and geophysical methods for studying the Upper Devonian reefs during exploratory drilling in the northern regions of the Perm Territory), In: Stratigrafiya i regional'naya geologiya vostoka Russkoy platformy i Zapadnogo Urala (Stratigraphy and regional geology of the east of the Russian platform and the Western Urals), Perm', 2009, pp. 72–82.

The article presents the results of increasing the efficiency of geological exploration at one of the key clusters of Rosneft Oil Company in Eastern Siberia. The increase in the efficiency of work is ensured due to the integration of field geophysical methods - geoelectric prospecting and vintage 2D seismic data. This allowed not only to significantly reduce the geological risks associated with the unique geology of the region, but also to reduce the cost of exploration.

The paper presents a brief description of the geological structure of the Yurubchen-Tokhomo oil and gas accumulation zone. As well as, the paper describes the main difficulties in separating Riphean sediments from the basement rocks based on vintage 2D seismic data. It is proposed to combine the seismic CDP method and the TEM method to separate the Riphean terrigenous-carbonate sediments from the basement granitoids. In addition, the paper describes the theoretical prerequisites of the TEM method using resistivity for the separation of the Riphean sedimentary rocks from the intrusive basement rocks. The integration of the methods are justified by using numerical modeling and the results of the analysis of well logging data. An approach to the complex analysis of the two methods at the qualitative level is demonstrated. This approach allows to greatly decrease the main limitations of each of the methods, thereby increasing the reliability of the data interpretation results, the success of subsequent exploration and reducing the risks of drilling into the unproductive basement rocks. The resulting geological model is fully consistent with the drilling results, which could not be achieved by only using the vintage 2D seismic data. A quantitative assessment of the change in the probability of geological success and an assessment of the value of information (VOI) obtained as a result of integration were carried out.

References

1. Mel'nikov N.V., Mel'nikov P.N., Smirnov E.V., The petroleum accumulation zones in the geological-prospecting regions of the Lena-Tunguska province (In Russ.), Geologiya i geofizika = Russian Geology and Geophysics, 2011, V. 52, no. 8, pp. 1151–1163.

2. Trofimuk A.A., Kuyumbo-Yurubcheno-Tayginskoe gazoneftyanoe mestorozhdenie supergigant Krasnoyarskogo kraya. Osnovy tekhniko-ekonomicheskogo obosnovaniya razrabotki (The Kuyumbo-Yurubcheno-Taiginskoye gas and oil field is a supergiant in the Krasnoyarsk Territory. Basics of a feasibility study for development), Novosibirsk: Publ. of OIGGM, 1992, 60 p.

3. Filiptsov Yu.A., Neftegazonosnost' verkhnego proterozoya zapadnoy chasti Sibirskoy platformy (Oil and gas content of the upper Proterozoic in the western part of the Siberian platform): thesis of doctor of geological and mineralogical science, Krasnoyarsk, 2015.

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

5. Kharakhinov V.V., Shlenkin S.I., Neftegazonosnost' dokembriyskikh tolshch Vostochnoy Sibiri na primere Kuyumbinsko-Yurubcheno-Tokhomskogo areala neftegonakopleniya (Oil and gas potential of the Precambrian strata of Eastern Siberia on the example of the Kuyumbinsky-Yurubcheno-Tokhomsky oil accumulation area), Moscow: Nauchnyy mir, 2011, 420 p.

6. Votintsev A.N., Krasil'nikova N.B., Oil and gas occurrence of the Siberian platform basement within the Kamovsky arch of the Baikitsky anteclise (In Russ.), Geologiya nefti i gaza = Russian Geology and Geophysics, 2019, no. 2, pp. 55–62.

7. Pospeev A.V., Buddo I.V., Agafonov Yu.A. et al., Sovremennaya prakticheskaya elektrorazvedka (Modern practical electrical exploration), Novosibirsk: Geo Publ., 2018, 231 p.

8. Mostovoy P.Ya., Shakirzyanov L.N., Ostankov A.V. et al., Decision making practice of applying electromagnetic surveys in different geological areas and geophysical conditions (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 2, pp. 26–30, DOI: 10.24887/0028-2448-2021-2-26-30

9. Antonov E.Yu., Matematicheskoe modelirovanie kvazistatsionarnykh elektromagnitnykh poley v dispergiruyushchikh i magnitnykh sredakh (Mathematical modeling of quasi-stationary electromagnetic fields in dispersive and magnetic media): thesis of doctor of physical and mathematical science, Novosibirsk, 2011.

10. Bratvold R.B., Bickel E.J., Lohne H.P., Value of information: the past, present, and future, SPE-110378-PA, 2009, DOI: https://doi.org/10.2118/110378-MS.

11. Sitnikov A.N., Butorin A.V., Timoshenko G.M., Vashevnik A.M., Application of Value of Information approach to seismic data for decreasing well drilling risks (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2016, no. 12, pp. 40–43.

Oil and gas reserves and resources are fundamental assets of any oil and gas company. They affect market value of companies, determine the basis and criteria for lending for banks, as well as the business activity and strategic planning when making the most important investment decisions. Estimation of reserves and resources provides a benchmarking for comparing companies with each other and is the basis for calculating depreciation and depletion of capital. Zarubezhneft JSC, as a company is operating not only in Russian Federation, but also abroad. In 2013 it was decided to make independent reserves audit according to the international classification SPE PRMS developed by the International Society of Petroleum Engineers (SPE) and the US Securities and Exchange Commission (SEC) in order to ensure transparency of financial reporting to the State and foreign partners. Since 2018, Zarubezhneft JSC started making its own assessment of reserves. This allowed the Company developed own competence and canceled independent auditor service by the end of 2020. All the necessary work is carried out by Corporate Reserves Group, which includes specialists from the Corporate Center and VNIIneft. The reserves audit process in Zarubezhneft JSC has become an effective, understandable and demanded tool for top management to plan, analyze and monitor the state of the company's reserves and resources, providing reliable and easily interpretable estimates for making management decisions. The continual development of automation of assessment processes has made it possible to reduce the time spent by specialists for performing routine operations, minimize the human factor, increase the time for analyzing obtained results and increase the reliability of the assessment.

References

1. Petroleum resources management system, SPE, 2018, Version 1.01, URL: https://www.millerandlents.com/wp-content/uploads/2020/03/2018-Petroleum-Resources-Management-System...

2. Vygon G., Inventory of reserves: from state expertise to national audit (In Russ.),  Neftegazovaya vertikal', 2019, no. 18/19, pp. 19–24.

3. Inventarizatsiya zapasov: neobkhodimost' sistemnykh izmeneniy (Inventory inventory: the need for systemic changes), VYGON Consulting, 2019, URL: https://vygon.consulting/products/issue-1701

4. Starinskaya G., Foreign auditors know more about oil in Russia than the state (In Russ.), Vedomosti, 2019, https://www.vedomosti.ru/business/articles/2019/12/26/819732-inostrannie-auditori.

5. Mavrina L., Foreign auditors will be banned from checking some Russian companies (In Russ.), Vedomosti, 2021, URL: https://www.vedomosti.ru/economics/articles/2021/04/26/867738-inostrannim-auditoram

Intensive study of the oil and gas content of the Permian system in the Samara region was carried out mainly in the fifties in connection with the identification and industrial development of oil and gas fields in the Pokhvistnevsko-Buguruslansky (Upper Permian deposits) and Kinel-Cherkassky (Upper and Lower Permian deposits) areas. By the mid-sixties, prospecting interest in Permian deposits had declined after the discovery of high-yield deposits in the carboniferous and Devonian deposits in the central part of the region. A common feature for the central and southern parts of the drilled territory is the discrepancy between the structural plans of the upper and Lower Permian. In addition, there is a local discrepancy between the structural plans inside the Kungurian and Kazanian strata (due to changes in the thickness of the halite layers). Due to the deep occurrence of subsalt deposits in the extreme south and in the center of the district, the technical equipment and economic conditions for drilling enterprises did not allow drilling on the subsalt Kungurian deposits. All these facts were the reason for the termination of structural drilling and its replacement with seismic exploration.  The Permian deposits were not studied purposefully, but during the drilling of deep wells, they were repeatedly recorded throughout the eastern part of the Buzuluk Depression. At the same time, there is reason to believe that the prospects for the oil and gas content of the Permian deposits are not fully disclosed, and with further improvement of their geological structure by modeling shooting spread of the common depth point method observation systems to select the optimal parameters, new oil deposits can be discovered in them. Relatively small depths of occurrence of promising Permian deposits (from 600-700 m in the central part to 1000-1200 m in the extreme south of the region), relatively simple geological drilling conditions determine high-quality testing and cost-effectiveness of work.

References

1. Kochubenko O.V., Aleksandrov A.A., Otsenka perspektiv neftegazonosnosti permskikh otlozheniy Buzulukskoy vpadiny Samarskoy oblasti (Assessment of the oil and gas potential of the Permian deposits of the Buzuluk depression of the Samara region), Samara: Publ. of Volga branch of IGiRGI, 1999, 191 p.

2. Kornienko A.A., Sozdanie tsifrovoy modeli geologicheskogo stroeniya verkhnego opornogo otrazhayushchego gorizonta osadochnogo chekhla v zone sochleneniya Buzulukskoy vpadiny i Zhigulevsko-Pugachevskogo svoda (Creation of a digital model of the geological structure of the upper key reflecting horizon of the sedimentary cover in the junction zone of the Buzuluk depression and the Zhigulevsko-Pugachevsky arch), Samara: Publ. of SNGEO, 2015, 97 p.

The problem of localization of fractured zones is one of the most important for the development of fractured reservoirs. Its relevance is determined by the fact that in most cases these zones are located unevenly in area, and at the same time it is hard to identify them by direct methods. The paper proposes a method for localizing zones with a high content of fractures associated with tectonic mechanisms of how it is forming. It is based on the assumption that the strain field determines the zones of fracture propagation using a design characteristic called the fracture intensity, which is expressed through the invariants of volumetric strain and the intensity of shear strain. The method allows to build a map of fracture intensity, as well as to determine the preferred direction of fractures. The method has been successfully tested at one of the oilfields in Russia. Two approaches to assessing the strain field are considered. Taking into account the applied relationships, they are called "geomechanical" and "tectonophysical". So, for the tectonophysical approach, structural data are required (the position of horizons, faults, which can be distinguished from seismic data, as well as, if available, information on the kinematics of these faults). The geomechanical approach additionally requires formation mechanical properties (Young's modulus and Poisson's ratio), Biot's ratio, rock density, and pore pressure.

References

1. Biot M.A., General theory of three dimensional consolidation, Journal of Applied Physics, 1941, V. 12, no. 2, pp. 155–164.

2. Gallagher R.H., Finite element analysis: Fundamentals, Pearson College Div., 1975, 420 p.

3. Zienkiewicz O., The finite element method in engineering science, London; New York: McGraw-Hill, 1971, 521 p.

4. Fadeev A.B., Metod konechnykh elementov v geomekhanike (Finite element method in geomechanics), Moscow: Nedra Publ., 1987, 221 p.

5. Skvortsov A.V., Triangulyatsiya Delone i ee primenenie (Delaunay triangulation and its application), Tomsk: Publ. of Tomsk University, 2002, 128 p.

6. Kudinov V.A., Tekhnicheskaya termodinamika i teploperedacha (Technical thermodynamics and heat transfer), Moscow: Yurayt Publ., 2019, 454 p.

7. Papadopoulos P., Introduction to the finite element method, Department of Mechanical Engineering, University of California, Berkeley, 2010, 204 p.

8. Antonov A.S., Parallel'noe programmirovanie s ispol'zovaniem tekhnologii OpenMP (Parallel programming using OpenMP technology), Moscow: Publ. of MSU,  2009, 77 p.

9. Balandin M.Yu., Shurina E.P., Metody resheniya SLAU bol'shoy razmernosti (Methods for solving large-dimensional simultaneous linear algebraic equations), Novosibirsk: Publ. of NSTU, 2000, 70 p.

Technologies of non-stationary reservoir flooding are a settled oil recovery method of oil production and reservoir pressure maintenance under the development of most hydrocarbon deposits in the Russian Federation. First of all, this is due to the feasibility, accessibility and low price of water sources for waterflooding. However, the water injection of creates a deferred problem – the inevitable, often water breakthrough, provoked by a sudden and irreversible change in water saturation. The problem of optimization and effective management of the process of non-stationary flooding remains an urgent task. The two-phase flowtheory of Buckley and Leverett does not take into account the loss of stability of the displacement front, provoking a step change and the triplicity of the water saturation value. Therefore, at one time, a mathematically simplified approach was proposed - a repeatedly differentiable approximation to exclude a "jump" in water saturation. Such a simplified solution results in negative consequences well-known from the practice of flooding, recognized by experts as "viscous instability of the displacement front", "finger-shaped displacement front", "dagger flooding of well products", "premature water breakthrough in producing wells", "fractal geometry of displacement front movement". The core of the problem is an attempt to predict the beginning of the loss of stability of the oil displacement front and to prevent its negative consequences on the water flooding in difficult conditions of interaction of hydrothermodynamic, capillary, molecular, inertial and gravitational forces.

In this study, the methods of catastrophe theory are used as a new approach for the analysis of nonlinear polynomial dynamical systems. For this purpose, a mathematical model of growth is selected and by solving the inverse problem, the initial coefficients of the system of differential equations of a two-phase flow are defines. A unified control parameter has been identified, which is used as a discriminant criterion of oil and water growth models for monitoring, control and optimizing the process of water flooding.

References

1. Kreyg F.F., Razrabotka neftyanykh mestorozhdeniy pri zavodnenii (Applied waterflood field development), Moscow: Nedra Publ., 1974, 191 p.

2. Dake L.P., The practice of reservoir engineering, Elsevier Science, 2001, 570 p.

3. Aziz Kh., Settari A., Petroleum reservoir simulation, Applied Science Publishers, 1979, 476 p.

4. Rose W., Rose D.M., “Revisiting” the enduring Buckley – Leverett ideas, Journal of Petroleum Science and Engineering, 2004, V. 45, pp. 263–290, DOI:10.1016/j.petrol.2004.08.001

5. Abbasi J., Ghaedi M., Riazi M., A new numerical approach for investigation of the effects of dynamic capillary pressure in imbibition process, Journal of Petroleum Science and Engineering, 2018, V. 162, pp. 44–54, DOI:10.1016/j.petrol.2017.12.035

6. Yonggang D., Ting L., Mingqiang W. et al., Leverett analysis for transient two-phase flow in fractal porous medium, CMES, 2015, V. 109–110, no. 6, pp. 481–504.

7. Charnyy I.A., Podzemnaya gidrogazodinamika (Underground hydraulic gas dynamics), Moscow – Leningrad: Gostoptekhizdat Publ., 1963, 396 p.

8. Barenblatt G.I., Entov V.M., Ryzhik V.M., Dvizhenie zhidkostey i gazov v prirodnykh plastakh (Movement of liquids and gases in natural reservoirs), Moscow: Nedra Publ., 1982, 211 p.

9. Nigmatullin R.I., Dinamika mnogofaznykh sred (The dynamics of multiphase media), Part 2, Moscow: Nauka Publ., 1987, 360 p.

10. Shakhverdiev A.Kh., Sistemnaya optimizatsiya protsessa razrabotki neftyanykh mestorozhdeniy (System optimization of oil field development process), Moscow: Nedra Publ., 2004, 452 p.

11. Mirzadzhanzade A.Kh., Shakhverdiev A.Kh., Dinamicheskie protsessy v neftegazodobyche: sistemnyy analiz, diagnoz, prognoz (Dynamic processes in the oil and gas production: systems analysis, diagnosis, prognosis), Moscow: Nauka Publ., 1997, 254 p.

12. Mandrik I.E., Panakhov G.M., Shakhverdiev A.Kh., Nauchno-metodicheskie i tekhnologicheskie osnovy optimizatsii protsessa povysheniya nefteotdachi plastov (Scientific and methodological and technological basis for EOR optimization), Moscow: Neftyanoe khozyaystvo Publ., 2010, 288 p.

13. Shakhverdiev A.Kh., Once again about oil recovery factor (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2014, no. 1, pp. 44–48.

14. Shakhverdiev A.Kh., System optimization of non-stationary floods for the purpose of increasing oil recovery (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 1, pp. 44–49, DOI:10.24887/0028-2448-2019-1-44-49

15. Shakhverdiev A.Kh., Shestopalov Yu.V., Mandrik I.E., Aref'ev S.V., Alternative concept of monitoring and optimization water flooding of oil reservoirs in the conditions of instability of the displacement front (In Russ.),Neftyanoe khozyaystvo = Oil Industry, 2019, no. 12, pp. 118–123, DOI:10.24887/0028-2448-2019-12-118-123

16. Shakhverdiev A.Kh., Some conceptual aspects of systematic optimization of oil field development (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2017, no. 2, pp. 58–63, DOI: 10.24887/0028-2448-2017-2-58-63

17. Shakhverdiev A.Kh., And Shestopalov Yu.V., Qualitative analysis of quadratic polynomial dynamical systems associated with the modeling and monitoring of oil fields, Lobachevskii journal of mathematics, 2019, V. 40, no. 10, pp. 1691–1706.

18. Shakhverdiev A.Kh., Shestopalov Yu.V., Kachestvennyy analiz dinamicheskoy sistemy podderzhaniya plastovogo davleniya s tsel'yu povysheniya nefteotdachi zalezhey (Qualitative analysis of a dynamic system for maintaining reservoir pressure in order to increase oil recovery), Proceedings of 14 International Conference “Novye idei v naukakh o Zemle” (New ideas in earth sciences), Moscow, 2-5 April 2019. – https://www.mgri.ru/science/scientific-practical-conference/2019-doc/tom%205.pdf

19. Thompson J. M. T, Instabilities and catastrophes in science and engineering, John Wiley & Sons, 1982, 226 p.

20. Arnol'd V.I., Teoriya katastrof (Catastrophe theory), Moscow: Nauka Publ., 1990, 128 p.

21. Nicolis G., Prigogine I., Self-organization in nonequilibrium systems: From dissipative structures to order through fluctuations, John Wiley & Sons, 1977, 512 p.

22. Gaiko V.A., On global bifurcations and Hilbert’s sixteenth problem, Nonlinear Phenomena in Complex Systems 3, 2000, no. 1, pp. 11–27.

The article presents a geometric method for comparative assessment of formation coverage in steady-state and cyclic waterflooding and an analytical algorithm to divide into groups the injection wells for cyclic waterflooding, taking into account the method of filtration flow redirection. The amount of injection well grouping options for cyclic waterflooding is large enough to calculate each at simulation model. An analytical algorithm has been developed to find the best option for grouping injection wells for cyclic waterflooding, taking into account the method of filtration flow redirection. The area of oil-saturated reservoir zones, additionally involved in production, and their corresponding mobile oil in place are used as the optimization criterion. The main directions of filtration flows are formed in a steady waterflooding and areas of the reservoir that are poorly covered by waterflooding appear. In the first half-cycle of the waterflooding, new directions of filtration flows are formed when some of the injection wells are shut down. Similarly, in the second half-cycle of waterflooding. By obtaining the resulting area of coverage of the oil in place by active production zones after two half-cycles and using the map of current mobile oil in place, we can determine the reserves involved in active production for this grouping of injection wells. The analysis showed that there is a sufficient correlation between the value of additionally covered current mobile oil in place as a result of filtration flow redirection, obtained by analytical evaluation, and technological efficiency, obtained by the results of calculations at simulation model. The results of the analytical evaluation significantly reduce the total time of calculations at simulation model, which allows in a short time to make a decision on the choice of the optimal case of cyclic waterflooding for implementation in the oilfield.

References

1. Kulushev M.M., Gil'miyanova A.A., Petukhov N.Yu. et al., Experience of implementing wellworks to change the direction of fluid filtration in the monolith block of the field of Western Siberia (In Russ.), Territoriya Neftegaz, 2020, no. 11–12, pp. 66–70.

2. Ovchinnikov K.A., Kovaleva G.A., Lebedeva A.V., The experience of oil recovery enhancement of carbonate reservoirs by the method of filtration flows direction change (In Russ.), Neftepromyslovoe delo, 2020, no. 6, pp. 12–16, DOI: 10.30713/0207-2351-2020-6(618)-12-16

3. Fomkin A.V., Petrakov A.M., Bench A.R. et al., Effect for method of changing fluid flow direction on the field with carbonate reservoir (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2014, no. 10, pp. 96–99.

4. Aubakirov A.R., Designing optimal technology cyclic waterflooding using hydrodynamic modeling (In Russ.), Ekspozitsiya Neft' Gaz, 2015, no. 7, pp. 40–44.

5. Ivanov A.N., Pyatibratov P.V., Aubakirov A.R., Dzyublo A.D., Justification of injection wells operating modes for cyclic waterflooding application (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 2, pp. 28–31, DOI: 10.24887/0028-2448-2020-2-28-31

6. Pyatibratov P.V., Aubakirov A.R., Assessing the impact of reservoir permeability anisotropy on the cyclic waterflooding effectiveness (In Russ.), Ekspozitsiya Neft' Gaz, 2016, no. 5, pp. 60–62.

7. Chertenkov M.V., Chuyko A.I., Aubakirov A.R., Pyatibratov P.V., Zones and regions selecting for cyclic waterflooding (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2015, no. 8, pp. 60–64.

8. Surguchev M.L., Tsynkova O.E., Sharbatova I.N. et al., Tsiklicheskoe zavodnenie neftyanykh plastov (Cyclical flooding of oil reservoirs), Moscow: Publ. of VNIIOENG, 1977.

9. Sharbatova I.N., Surguchev M.L., Tsiklicheskoye vozdeystviye na neodnorodnyye neftyanyye plasty (Cyclical effects on heterogeneous oil layers), Moscow: Nedra Publ., 1988, 121 p.

10. Kostyuchenko S.V., Direct calculation of the current sweep efficiency at geologic-hydrodynamic modeling (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2006, no. 10, pp. 58-61.

11. Kostyuchenko S.V., Cheremisin N.A., Direct calculation of sweep efficiency and localization of current recoverable oil reserves in digital models (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 7, pp. 94–98, DOI: 10.24887/0028-2448-2019-7-94-98

12. Mett D.A., Aubakirov A.R., The study of signal changes dynamics from disturbing well to observation well (In Russ.), Ekspozitsiya Neft' Gaz, 2017, no. 1, pp. 40–43.

The challenges related to transforming asset management business processes are caused not only by the deterioration in quality and oil reserves depletion, but also by a more significant level of assets digitalization. A huge amount of information from numerous sensors and measuring devices have begun to accumulate in corporate data warehouses, computing capacities and transmission channels have to process an increasing amount of data, new computational algorithms have been built, which opened up the possibility of implementing digital solutions that automatically process huge arrays of field information and data from service companies, systematize the information through a wide range of algorithms, and offer ready-made robust solutions that allow to achieve target production levels.

The purpose of this study is to demonstrate a comprehensive solution to managing the physical (production) potential (operational and technological) of a production company using modern digital information systems to automatically assess and select economic scenarios for field development targets, form a unified base of wellwork, as well as select first-priority scenarios, implement and monitor their performance, and determine critical deviations to adjust the scenarios and identify the best practices. The studied solution covers the entire production well stock, including injection and other wells. It consists in finding targeted opportunities to unlock the production potential of each well using various types of wellwork or their combinations. During the assessment process both wellwork available for implementation and locked-potential wells characterized by a set of constraints (geological, technological or economic) are identified. Therefore, in addition to a unified wellwork base, the solution also results in the following: a request for the search for new technologies, reengineering the field infrastructure, transformation of a field development system. And here we are talking about a targeted, well-by-well request, which is digitized.

References

1. Yudin E.V., Khabibullin R.A., Smirnov N.A., New approaches to gaslift and ESP well stock production management (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 6, pp. 67–73, DOI: 10.24887/0028-2448-2021-6-67-73

2. Vogel J.V., Inflow performance relationships for solution gas drive wells, Journal of Petroleum Technology, 1968, V. 20, no. 1, pp. 83–92, DOI: 10.2118/1476-PA.

3. Mishchenko I.T., Skvazhinnaya dobycha nefti (Oil production), Moscow: Neft’ i gaz Publ., 2003, 816 p.

4. Babu D.K., Odeh A.S., Productivity of a horizontal well. Appendices A and B, SPE-18334-MS, 1988, https://doi.org/10.2118/18334-MS

5. Li H., Jia Z., Wei Z., A new method to predict performance of fractured horizontal wells, SPE-37051-MS, 1996, DOI: https://doi.org/10.2118/37051-MS

In recent years, interest in the use of polymer systems to improve the efficiency of oil production has grown significantly, and the intensification of their use has been noted in a number of oil-producing countries, including Brazil, Venezuela, Canada, China, Colombia, the United States, Russia, France. The result of pilot works on the injection of SPA-Well reagent into the injection well of the Zhalgiztobe field, which has an oil viscosity of more than 800 mPa·s, a layered heterogeneous reservoir and a core permeability spread of more than 200 times, are presented. The waters of the Zhalgiztobe field are chlorocalcium brines with mineralization of 35-55 g/l, which significantly reduce the viscosity of the polymer solution relative to the polymer mixing in fresh water. A feature of the SPA-Well reagent is its hydrophobicity, however, allowing it to be used for mxing in injected water. The SPA-Well reagent is actively retained in a porous media, practically without being washed out into production wells, unlike traditional polymers. The results of experimental studies of the reagent solution on the water of the deposit are presented. Experiments have shown that the SPA-Well reagent has a viscosity of 30 mPa·s when injected, reaching values of hundreds of thousands of millipascal-second in reservoir conditions. Pilot works on the injection of SPA-Well solution at the site of injection well No. 218 in a total volume of 5.3 tons in the form of a fractional rim were carried out on December 11-16, 2019. The technological effect of more than 1300-2200 tons of additional production or 300-400 tons per 1 ton of injected reagent was obtained. In accordance with the mechanism of influence of thickening viscoelastic systems on the process of oil displacement, the technological effect will only increase over time (by increasing the volume of injection of pushing water).

References

1. Grigorashchenko G.I., Zaytsev Yu.V., Kukin V.V. et al., Primenenie polimerov v dobyche nefti (The use of polymers in oil recovery), Moscow: Nedra Publ., 1985, 1978, 213 p.

2. Surguchev M.L., Vtorichnye i tretichnye metody uvelicheniya nefteotdachi plastov (Secondary and tertiary methods of enhanced oil recovery), Moscow: Nedra Publ., 1985, 308 p.

3. Abidin A.Z., Puspasari T., Nugroho W.A., Polymers for enhanced oil recovery technology, Procedia Chem., 2012, V. 4, pp. 11–16.

4. Khavkin A.Ya., Fizika neftegazovykh plastov i nelineynye yavleniya (Physics of oil and gas reservoirs and nonlinear phenomena), Moscow: Publ. of Gubkin University, 2019, 288 p.

5. Kadet V.V., Khavkin A.Ya., Khavkin B.A., On the trend of polymer EOR-technologies (In Russ.), Estestvennye i tekhnicheskie nauki, 2020, no. 12, pp. 138–145.

6. Dupuis G., Nieuwerf J., A cost-effective technique to enhance oil recovery and reduce carbon intensity with polymer flooding and modular skids (In Russ.), Territoriya NEFTEGAZ, 2020, no. 9–10, pp. 38–41.

7. Patent RU 2723797 C1, Composition for increasing oil production, Inventors: Fakhretdinov R.N., Selimov D.F., Tastemirov S.A., Yakimenko G.Kh., Pasanaev E.A.

8. Fakhretdinov R.N., Khavkin A.Ya., Imanbaev B.A., Possibilities of modern gel-forming reagents to increase oil production at kalamkas oil field (In Russ.), Estestvennye i tekhnicheskie nauki, 2019, no. 10, pp. 197–201.

9. Fakhretdinov R.N., Khavkin A.Ya., Imanbaev B.A., Shilanov N.S., Application peculiarities of the polymer-gel-forming single-component reagent SPA-WELL in technologies well injection capacity regulation (In Russ.), Estestvennye i tekhnicheskie nauki, 2020, no. 1, pp. 99–102.

10. Fakhretdinov R.N., Khavkin A.Ya., Imanbaev B.A. et al., Applicability research the polymer-gel-forming system at a oil field with high-viscosity oil (In Russ.), Estestvennye i tekhnicheskie nauki, 2020, no. 1, pp. 103–108.

11. URL: https://www.cse-inc.ru/.

12. Fakhretdinov R.N., Fatkullin A.A., Selimov D.F. et al., Laboratory and field tests of AC-CSE-1313-A reagent as the basis of water control technologies (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 6, pp. 68–71, DOI: 10.24887/0028-2448-2020-6-68-71.

13. Ayshuak K., Perspektivy mestorozhdeniya Zhalgiztobe (Prospects for the Zhalgiztobe field), URL: http://nomad.su/?a=4-201004190015.

14. Imanbaev B.A., Torbeev T., Engel's A.A., Khavkin A.Ya., Primenenie potokootklonyayushchey tekhnologii na neftyanom mestorozhdenii Zhalgiztobe (Application of flow diverting technology at the Zhalgiztobe oil field), Proceedings of III International Scientific and Practical Conference named after V.I. Kudinova “Sovremennye tekhnologii izvlecheniya nefti i gaza. Perspektivy razvitiya mineral'no-syr'evogo kompleksa (rossiyskiy i mirovoy opyt)” (Modern technologies for oil and gas extraction. Prospects for the development of the mineral resource complex (Russian and world experience)), 21-22 May 2020, Izhevsk: Udmurtskiy universitet Publ., 2020, pp. 69–73.

15. Imanbaev B.A., Bisekenov T., Sagyndikov M.S., Khavkin A.Ya., Application of flow-diverting procedure at Zhalgiztobe oil field (In Russ.), Neft'. Gaz. Novatsii, 2021, no. 3, pp. 9–12.

16. RD 153-39.1-004-96, Metodicheskoe rukovodstvo po otsenke tekhnologicheskoy effektivnosti i primeneniya metodov uvelicheniya nefteotdachi (Guidelines for assessing the technological effectiveness of enhanced oil recovery methods), Moscow: Publ. of VNIIneft, 88 p.

17.  Savel'ev V.A., Tokarev M.A., Chinarov A.S., Geologo-promyslovye metody prognoza nefteotdachi (Field-geologic methods of oil recovery forecast), Izhevsk: Udmurt University, 2008, 147 p.

18. Kazakov A.A., Metody kharakteristik vytesneniya nefti vodoy (Methods for the characteristics of oil displacement by water), Nedra Publishing House, 2020, 276 p.

The methods of improving the hydraulic fracturing technology for terrigenous and carbonate reservoirs of the fields of Udmurtneft named after V.I. Kudinov are considered, which make it possible to effectively stimulate wells taking into account complicated geological conditions. For terrigenous reservoirs, which include Devonian deposits, hydraulic fracturing makes it difficult to have nearby water-saturated layers from the interval of stimulation. The complexity of stimulation of carbonate reservoirs represented by medium carbon deposits, the main factors complicating hydraulic fracturing are a large floor of oil capacity (up to 150 m), high partition of productive layers, as well as a significant difference in the geological, physical and geomechanical properties of nearby layers, processing of which is impossible separately. The use of traditional hydraulic fracturing technologies for wells leads to breakthroughs in water-saturated formations or ineffective stimulation of the target reservoir, therefore there is a need to optimize the hydraulic fracturing technology. The article presents the technological solutions proposed for each factor complicating hydraulic fracturing. For terrigenous reservoirs (Visean Stage), acid injection before hydraulic fracturing, refusal of mini-hydraulic fracturing and a gradual increase in fluid viscosity during the main hydraulic fracturing process were recommended. When highly partitioned formations (Moscovian Stage) are stimulated with large perforation intervals, hydraulic fracturing is carried out with a proppant filling of the lower intervals during the injection process. This method of hydraulic fracturing is implemented according to the following scheme: at first the lower penetrated horizon is stimulated, and then the proppant agent is put to the bottomhole to the specified interval of perforation, after setting of the sand (proppant agent) in the wellbore the reservoir is stimulated through the upper intervals. In conditions of nearby water- or gas-saturated undesirable interlayers (Tournaisian Stage), it is effective to conduct hydraulic fracturing with a step-by-step, alternating with stops, and injection of acid stages with a gradual increase in the injection rate and subsequent fixing of the created crack with a proppant. In order to intensify production from simultaneously developed formations with different properties, it is recommended to conduct hydraulic fracturing according to an adaptive design, i.e., modified during the injection process.

The proposed methods will improve the efficiency of hydraulic fracturing, perform effective stimulation of wells in complicated geological conditions, as well as increase the pool of candidate wells for hydraulic fracturing.

 References

1. Shekhodanov V.A., Provorov V.M., Fedorchuk Z.A., Sharonov L.V., Pogrebnyak M.M., Geologiya i neftenosnost' Udmurtskoy ASSR (Geology and oil-bearing capacity of the Udmurt ASSR), Izhevsk: Udmurtiya Publ., 1976, 128 p.

2. Topal A.Yu., Firsov V.V., Usmanov T.S. et al., Regional aspects of hydraulic fracturing in Udmurtneft OJSC (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 4, pp. 45–48, DOI: 10.24887/0028-2448-2020-4-44-48

3. Topal A.Yu., Usmanov T.S., Zorin A.M. et al., Introduction of the acid and proppant hydrofracturing technology at Udmurtneft fields (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2018, no. 3, pp. 34–37, DOI: 10.24887/0028-2448-2018-3-34-37

4. Cleary M.P., Analysis of mechanisms and procedures for producing favourable shapes of hydraulic fractures, SPE-9260-MS, 1980.

5. Sharafeev R.R., Kondrat'ev S.A., Novokreshchennykh D.V. et al., Experience in propant hydraulic fracturing without a mini-frac stage (In Russ.) Neftepromyslovoe delo, 2021, no. 1, pp. 24–29, DOI: 10.33285/0207-2351-2021-1(625)-24-29

Hydraulic fracturing is currently a necessary part of the unconventional hydrocarbon reserves development. The efficiency of hydraulic fracturing is influenced by a large number of factors, one of which is the quality of the near-fracture zone of the formation, the so-called fluid loss damage zone. The flow rate and productivity index of the well significantly depend on the parameters of this zone. Therefore, it is important to have a way to estimate these parameters. The following problem was considered: in an infinite reservoir saturated with a single-phase fluid, there is a well that is intersected by a symmetric vertical hydraulic fracture along its entire thickness. The formation around the fracture has a damaged zone that has reduced reservoir properties. The hydraulic connection between the reservoir and the well is realized only through the lateral surface of the fracture. At the initial moment of time, the pressure in the formation and the fracture is the same, and the well is put into production at a constant flow rate. The solution obtained by application of the Laplace integral transform method, is presented in the form of the dependence of the bottomhole pressure on time and the hydrodynamic parameters of the system reservoir – skin zone – hydraulic fracture. This expression is essentially a ‘type curve’ equation that can be used to solve inverse problems of reservoir hydrodynamics and interpretation problems of well testing. The solution includes a parameter that can be considered as a value that determines the additional pressure drop in the skin zone, which in its meaning coincides with the skin factor.

References

1. Khabibullin I.L., Khisamov A.A., Modeling of unsteady filtration around the well with vertical hydraulic fracture (In Russ.), Vestnik Bashkirskogo gosudarstvennogo universiteta, 2017, V. 22, no. 2, pp. 309–314.

2. Khabibullin I.L., Khisamov A.A., Unsteady flow through a porous stratum with hydraulic fracture (In Russ.), Izvestiya RAN. Mekhanika zhidkosti i gaza = Fluid Dynamics, 2019, no. 5, pp. 6–14, DOI: 10.1134/S0568528119050050.

3. Nagaeva Z.M., Shagapov V.Sh., Elastic seepage in a fracture located in an oil or gas reservoir (In Russ.), Izvestiya RAN. Prikladnaya Matematika i Mekhanika = Journal of Applied Mathematics and Mechanics, 2017, V. 81, no.  3, pp. 319–329.

4.  Barenblatt G.I., Entov V.M., Ryzhik V.M., Dvizhenie zhidkostey i gazov v prirodnykh plastakh (Movement of liquids and gases in natural reservoirs), Moscow: Nedra Publ., 1982, 211 p.

5. Cinco-Ley H., Samaniego V. F., Effect of wellbore storage and damage on the transient pressure behavior of vertically fractured wells, SPE-6752-MS, 1977, DOI: 10.2118/6752-ms.

6. Cinco-Ley H., Samaniego V.F., Transient pressure analysis: Finite conductivity fracture case versus damaged fracture case, SPE-10179-MS, 1981,  DOI: 10.2118/10179-MS

7. Lavrent'ev M.A., Shabat B.V., Metody teorii funktsiy kompleksnogo peremennogo (Methods of the theory of functions of a complex variable), Moscow: Nauka Publ., 1987, 688 p.

8. Gringarten A.C., Type-curve analysis: What it can and cannot do, Journal of Petroleum Technology, 1987, January, V. 39, no. 1, pp. 11–13, DOI: 10.2118/16388-pa.

The article provides an innovative approach to prioritizing the installation of soil thermal stabilizers when performing activities based on the results of geotechnical monitoring of oil and gas fields. The urgency of the problem lies in the significant risks of direct damage during thawing of permafrost soils. The proposed method is based on the use of the hierarchy analysis method. The method allows to reduce the influence of subjective factors and improve the quality of management decisions of the operation services of oil and gas producing enterprises. The article presents the factors influencing the priority of the installation of thermal stabilizers as a way to ensure the safety of objects when the temperature regime of soils changes. The use of soil thermal stabilizers is accepted as the most effective way to regulate the thermal state of the soil. It is proposed to decompose the task into a 3-level hierarchy. Next, matrices are created for pairwise comparisons of factors and structures with each other, depending on various criteria. The comparison is performed using a scale of relative importance. For the resulting comparison matrices, vectors of local priorities are formed, which express the relative influence of a set of elements on an element of the adjacent top level. The consistency of local priorities is determined by calculating the consistency index and the consistency ratio. Depending on the size of the matrices, the consistency ratio is compared with the corresponding value of random consistency to check the reliability of judgments in pairwise comparisons. The final stage is the preparation of a table of generalized priorities, in accordance with which a decision is made on the ranking of priorities for the appointment of measures for thermal stabilization of soils. The article gives an example of choosing the optimal installation of soil thermal stabilizers for 3 structures based on 4 criteria. The proposed technology can be used to determine the priorities of the geological and technical measures network in the fields, where previously the observation of deformations of structures and temperature control was not provided.

References

1. Informatsionnyy byulleten' “Izmenenie klimata”, 2020, V. 87, URL: http://global-climate-change.ru/downl/byulletenyo/Izmenenie_klimata_N87_OctNov_2020.pdf

2. Gilev N.G., Zenkov E.V., Poverennyy Yu.S. et al., Optimization of capital costs for pile foundations during construction of oil and gas production facilities on permafrost soils (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 11, pp. 46–49, DOI: 10.24887/0028-2448-2019-11-46-49

3. Saati T.L., Decision making for leaders: The analytical hierarchy process for decisions in a complex world, Wadsworth, 1988.

For the past 10 years Russia has seen an active increase in oil and gas production. The main reason for this is the increase in the number of oil fields being developed, while the development of each field requires the involvement of many tangible and intangible resources and has a long duration in time. However, we can say that the construction of wells has become an ordinary matter and is carried out according to a common technology, and therefore is being formed a new concept – "conveyor" construction, that is when the fields are unified and have a standard solution. Based on this, a promising way to reduce costs and losses during construction is lean manufacturing technology.

This article covers the basics of lean manufacturing, its goals and tools, as well as the advantages of the technology used. A general algorithm of actions is considered to understand the processes of constructing of oil and gas wells. Based on these data, a cross-comparison of lean production and well construction is carried out and tools are formed for improving the efficiency of work. The focus of the article is on computer technologies and ensuring the safety of employees at the oil field. Besides that, we offer tools for optimizing the processes of well construction and improving the skills of employees. The article also describes the general principle of operation of a new lean manufacturing system based on computer technologies and suggests key performance indicators for evaluating the quality of the using technologies.

References

1. Roos D., Womack J.P., Jones D.T., The machine that changed the world: The story of lean production, Harper Perennial, 1991.

2. Womack J.P., Jones D.T., Lean thinking: Banish waste and create wealth in your corporation, Free Press, 2003, 396 p.

3. URL:  https://gazprom-neft-ru.turbopages.org/gazprom-neft.ru/s/press-center/sibneft-online/archive/2017-ap...

4. Fattakhov R., Opyt vnedreniya berezhlivogo proizvodstva v dobyche nefti: Leninogorskneft' (Experience in implementing lean production in oil production: Leninogorskneft), URL: http://www.up-pro.ru/library/production_management/ lean/lean-neft.html

5. URL: https://www.gazprom-neft.ru/press-center/sibneft-online/archive/2018-february/1439928/

Assessment of the state of the environmental components of the Sakhalinsky and Vostochno-Sakhalinsky licensed areas is of particular interest, since these areas are located in two physico-geographical provinces with completely different geochemical conditions for landscape formation - the Surgut bog and the Ob-Irtysh floodplain. The main watercourses located in the areas under consideration originate in the overwatered landscapes of the bogs of the Middle Ob region; therefore their waters are characterized by high acidity, a large amount of organic matter, and a low content of dissolved oxygen. The acidic reaction of the medium and the high content of organic substances predetermine the active mobility of many trace elements in surface waters, primarily iron and manganese, to a lesser extent zinc, copper, vanadium, chromium, titanium, lead, nickel and aluminum. The transit watercourse is the Ob River, flowing in the southern part of the Sakhalin area. Originating thousands of kilometers away in the mountains of Southern Siberia, the river receives various pollutants along its entire length. Therefore, its waters in the Middle Ob region are heavily polluted, including by substances that are associated with oil and gas production. Thus, when assessing the current state of surface waters, the influence of external pollutants should be taken into account. In the bottom sediments of water reservoirs on the territory of oil and gas fields the accumulation of oil products was not recorded. The content of petroleum products, as well as other substances, is close to the background indicators determined before the start of the operation of the Zapadno-Sakhalinskoye, Yavinlorskoye and Vostochno-Sakhalinskoye fields. In addition to water and bottom sediments, soils are an indicator for assessing the quality of the natural environment. Soils also serve as the basis for vegetation cover, species diversity and productivity. Swamp soils prevailing in the subsoil are characterized by a low content of trace elements, some of which are extremely important for the development of plants. In the soils of riverine terraces and floodplains of large rivers, the content of trace elements is higher, which contributes to an increase in the biodiversity of the vegetation cover.

References

1. Resolution of the Government of the Khanty-Mansi Autonomous Okrug-Yugra no. 485-P of 23.12.11. “O sisteme nablyudeniya za sostoyaniem okruzhayushchey sredy v granitsakh litsenzionnykh uchastkov na pravo pol'zovaniya nedrami s tsel'yu dobychi nefti i gaza na territorii Khanty-Mansiyskogo avtonomnogo okruga-Yugry” (On the system for monitoring the state of the environment within the boundaries of licensed areas for the right to use subsoil for the purpose of oil and gas production in the Khanty-Mansiysk Autonomous Okrug-Yugra).

2. Zhirnova T.L., Malyshkina L.A., Patrina T.A. et al., Determination of the content of petroleum hydrocarbons in surface waters and bottom sediments by chromatography-mass spectromy (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2006, no. 2, pp. 116–117.

3. Resolution of the Government of the Autonomous Okrug No. 441-P dated 10.11.04. “Predel'no dopustimyy uroven' (PDU) soderzhaniya nefti i nefteproduktov v donnykh otlozheniyakh poverkhnostnykh vodnykh ob"ektov na territorii Khanty-Mansiyskogo avtonomnogo okruga-Yugry” (Maximum permissible level (MPL) for the content of oil and oil products in bottom sediments of surface water bodies on the territory of the Khanty-Mansiysk Autonomous Okrug-Yugra).