Articles

Geology

Development of the northern (including the Kara sea) and northeastern territories of Western Siberia (Yamal peninsula)

Yurova M.P.

DOI: 10.24412/2076-6785-2023-5-20-22

Abstract
The northern (including the Kara Sea) and northeastern territories of Western Siberia (the Yamal Peninsula) are being considered, which in the near future may become a priority territory in which gas deposits will be discovered on deep horizons (Permo-Triassic). This is confirmed by the interpretation of seismic profiles in the north-west of the Yamalo-Nenets Autonomous District (Paleozoic with a capacity of 1 500 m). Paleozoic terrigenous deposits are common within the South Kara syneclise.

Systematization of mega-reservoir accumulations of oil and gas in the sedimentary deposits

Punanova S.A., Samoilova A.V.

DOI: 10.24412/2076-6785-2023-5-16-19

Abstract
Based on the analysis and generalization of factual material, the article systematizes ideas about the formation of oil and gas mega-reservoirs in the sedimentary cover of oil and gas basins in Russia and the world. These are accumulations of hydrocarbons that accumulate large reserves both in traditional reservoirs and in reservoirs of unconventional low-porous shale formations, in reservoirs with hard-to-recover reserves of extraviscous
oils and natural bitumen deposits, as well as in reservoirs of decompacted ledges of the crystalline basement.

Nalysis of statistical values between structural surfaces on the test site in order to increase the reliability of exploration

Anisimova L.Z., Koluzaeva K.Yu., Anisimova L.G.

DOI: 10.24412/2076-6785-2023-4-10-14

Abstract
This article is devoted to the problems of increasing the degree of reliability of structural constructions at deposits based on the use of “isopachic triangle” methods and analysis of correlation coefficients of structural plans. In the course of work on the article, the analysis of statistical values between the structural surfaces of the structural surfaces of sedimentary formations of the tested area in the south-eastern part of the Republic of Tatarstan was carried out; namely, the correlation coefficients of the structural plans of the roof of the horizons were calculated and an isopachic triangle was constructed along the roof surfaces and isopachite between the horizons. The analysis of thickness variations will allow the authors to assume that during the development of structural plans in the targeted area, tectonic changes or endogenous processes that are tracked from the roof of the Tournai to the Tastuba horizon are the dominant factor.

Materials and methods
According to the constructed structural maps, the correlation coefficients were calculated by using mathematical methods. To determine the sequence of development of a number of surfaces, the method of “isopachic triangle” was used in the construction of paleostructural maps.

Keywords
isopachic triangle, structural maps, isopachite maps, paleosoic sediments, spatial analysis

Adaptation of methodological recommendations for assessing geological risks on the example of the territory of the South-East of the Yamalo-Nenets Autonomous District

Levkovich O.S., Mikheev Yu.V., Fishchenko A.N., Sokolnikova A.A., Sidorov D.A., Snokhin A.A., Hismatullina L.I.

DOI: 10.24412/2076-6785-2023-3-46-51

Abstract
The efficiency of exploratory drilling largely determines the economic prospects for the development of the territory. When conducting prospecting and exploration for oil and gas, companies strive to reduce the negative results (30–40 %), and for this purpose they perform an assessment of geological uncertainty and various methods of accounting for geological risks. According to modern concepts, geological risk is understood as the probability of a negative result when searching for a deposit at the research site. The inverse value of geological risk is the success rate of exploration.

Materials and methods
The work is based on the results of geophysical, lithological, petrophysical studies, as well as the results of basin modeling.
The assessment of geological risks was carried out for 2 400 promising objects.

Keywords
Western Siberia, south-east of the Yamalo-Nenets Autonomous District, geological risk, fluid stress, facies, deposit, migration, oil and gas mother rocks, hydrocarbon resource potential

Calculation of the stress state at the Severo-Komsomolskoye field using the new corporate 3D simulator RN-SIGMA

Ardislamova D.R., Davletova A.R., Zakirzyanov Sh.I., Pestrikov A.V., Sudeev I.V., Fedorov A.I., Shamsutdinova E.R., Khakimov A.A., Abushaev R.N.

DOI: 10.24412/2076-6785-2023-3-38-43

Abstract
The article describes the development of a new tool for calculating the stress-strain state of fields with a complex geological structure in the software package «RN-SIGMA». The computational core allows to make calculations within the framework of elastic models on standard grids (angular point geometry) used in hydrodynamic and geological modeling. The computational core has been tested on a number of examples, including the construction of a model of a real part of the Severo-Komsomolskoye field. The development of new computing core will provide specialists of the PJSC Rosneft Oil Company with an import-independent tool for building 3D geomechanical models.

Materials and methods
When developing the computational core, finite element modeling methods were used to solve the problem of elastic equilibrium of the reservoir, as well as analytical solutions and third-party software products for performing test calculations.

Keywords
geomechanics, geomechanical modeling, formation stress state, geomechanical 3D simulator

Methods of complex reinterpretation of geophysical data in the search for oil deposits in the terrigenous devonian sediments on territory of Tatarstan

Andreeva E.E., Borisov A.S., Baranova A.G., Valeeva A.V., Koluzaeva K.Yu.

DOI: 10.24412/2076-6785-2023-3-32-37

Abstract
The article deals with the techniques of kinematic and dynamic analysis of time sections of the common depth point method (CDPM) in combination with the data of gravity and magnetic exploration. Seismic velocity, as a petrophysical indicator of precipitation characteristics, is closely related to lithology, porosity, density, permeability, oil and water saturation. Magnetic prospecting finds application in the identification and tracing of discontinuous violations of the foundation, in predicting the distribution areas of hydrocarbon traps that are genetically related to zones of tectonic fracturing. The fracture zone is a weakened section of the section characterized by a density deficit, in the local gravity field it is reflected by negative anomalies of ∆g loc. The performed research allows the authors to conclude about the high efficiency of the proposed methods of complex reinterpretation of geophysical data in the search for oil deposits in the terrigenous devonian on the territory of Tatarstan.

Materials and methods
The work uses materials of geological exploration, in particular the results of exploration geophysics for the search for hydrocarbon accumulations. A comprehensive reinterpretation and comparison of data makes it possible to increase the probability of detecting new hydrocarbon deposits.

Keywords
terrigenous devonian sediments, complex interpretation, magnetic exploration, gravity exploration, seismic exploration

Reasons for the formation of an inclined water-oil contact of the Jurassic layer of the Festival deposit

Kuziv K.B.

DOI: 10.24412/2076-6785-2023-3-26-30

Abstract
In the process of creating geological models of oil deposits in order to assess hydrocarbon reserves, problems arise in substantiating the hypsometric position of the OWC surface (oil-water contact). The analysis of geological and geophysical materials shows that in nature there are practically no deposits where the surface of the OWC could be represented as a horizontal surface. The article discusses the regularities of the position of the water-oil contact of the reservoir of the productive formation U1 of the Festivalnoye field, identified in the process of geological modeling based on the analysis of the oil and gas bearing system.

Materials and methods
The results of geophysical studies of wells, as well as data on the reservoir geophysical interpretation of the deposit. Analysis of the relationship between the marks of structural surfaces and the position of the oil – water contact. Paleotectonic analysis. Justification of inclined oil-water contact.

Keywords
Western Siberia, Jurassic deposits, inclined oil-water contact, tectonics

Tectonic development of the southern part of the Mansi syneclise in the mesozoic-cenozoic time (Western Siberia)

Kuznetsov R.O.

DOI: 10.24412/2076-6785-2023-3-19-25

Abstract
A technique of paleotectonic analysis was applied to restore the tectonic development of the southern part of the Mansiysk syneclise, taking into account rock compaction effect. It has been quantitatively confirmed that the main increase in the amplitude of structures of the southern part of the Mansiysk syneclise occurred in Cretaceous; during the Cenozoic stage of the development of the territory, there was no a significant increase in the amplitude of the structure. The results of the tectonic development analysis are a basis for reconstructions of naftidogenesis processes and a forecast of oil and gas fields.

Materials and methods
Materials: information from multi-scale geological and geophysical studies, including core studies, well logging interpretations, regional and local seismic data.
Methods: well logging and seismic data interpretation techniques, paleotectonic method, methods of mathematical modeling of the evolution of the sedimentary basin cover were used.

Keywords
sedimentary cover of the West Siberian geosyneclise, tectonic development, paleostructural sections, rock compaction effect, oil and gas fields

Search for new oil and gas accumulation objects in the Lower-Middle Jurassic complex of the Kara-Yamal-Gydan region of Western Siberia

Zinatullina L.I.

DOI: 10.24412/2076-6785-2023-3-14-17

Abstract
The article presents the results of paleotectonic reconstructions of poorly studied deep-lying Lower-Middle Jurassic deposits
of the Kara-Yamal-Gydan region of gas and oil accumulation. Promising, from the point of view of oil and gas accumulation, objects in these complexes are identified. The regime of paleotectonic movements during the Lower-Middle Jurassic time of geological history in the study area has been studied. The results obtained allowed us to draw conclusions about new objects of oil and gas accumulation.

Materials and methods
Using the software package and modeling technologies “PetroMod” of the company “Schlumberger”, the reconstruction of the evolution of the sedimentary basin throughout the entire geological history of development was carried out. Methods of basin analysis and analysis of hydrocarbon systems were applied. The objects of study were the Lower-Middle Jurassic deposits of the Kara-Yamal-Gydan region.

Keywords
oil and gas prospects, Western Siberia, pre-Jurassic deposit,
Lower-Middle Jurassic deposit, Yamal Peninsula, Gydan Peninsula, paleotectonic reconstructions

Hydrogeochemical studies as an additional tool for the analysis of oil field development

Lyalin A.A., Vasiliev V.V., Merkulov A.V.

DOI: 10.24412/2076-6785-2023-2-19-22

Abstract
To analyze the development of an oil field, many different tools are used, such as field-geophysical studies, hydrodynamic studies, permanent geological and technological models, etc. At the same time, the information obtained from the results of hydrogeochemical analysis, which carries valuable data on the ongoing processes in the reservoir, including in individual wells, is often not fully used. The authors of the article propose a mathematical tool for analyzing hydrogeochemical data, which allows analyzing the processes of reservoir flooding, including existing problems. The essence of the method is to identify deviations of the component composition when mixing reservoir and injected water. This analysis makes it possible to identify a discrepancy between the percentage of components and the volume percentage of injected and reservoir water, which gives additional information about the flooding process, as well as possible problems in the wells. This method does not require any additional costs for special studies and uses standard hydrogeochemical information obtained in the field. The proposed approach can serve as an additional tool for analyzing the development of oil fields.


Materials and methods
The analysis of hydrogeochemical data is carried out using the mathematical tool proposed by the authors. Possible deviations (behind-the-casing flows, water interactions with the rock and with each other, etc.) occurring in wells during flooding have been identified.

Keywords
hydrogeochemical methods; analysis of reservoir engineering; maintenance of reservoir pressure; injected water; reservoir water; associated water; physical properties; chemical composition; percentage; mathematical tool

On the significance of sedimentation-tectonic processes for the structure of local uplifts in space and time

Andreeva E.E., Baranova A.G., Khaziev R.R., Valeeva A.V., Khairtdinov R.K., Ionov G.M.

DOI: 10.24412/2076-6785-2023-2-13-16

Abstract
In the course of the work, structural maps were constructed and analyzed on the surfaces of the horizons of the lower and middle carboniferous, as well as maps of the isopachite local uplift of one of the deposits of Tatarstan. Three separate domes, northern, central and eastern, have been installed on the studied uplift of the deposit. To determine the sequence of development of a number of surfaces, when constructing paleostructural maps, the authors used the “isopachic triangle” method, according to the constructed maps, the authors received information about the movements, structural forms and the relationship of these forms at different stages of geological history.

Materials and methods
According to logging diagrams and conclusions of well interpretation, the values of the absolute roof marks of the vereyan, bashkirian, tulian, bobrikovian, tournaian and upino-malevian sediments were removed. Structural maps, as well as isopachite maps between the deposits of the middle and lower carboniferous, were constructed from the removed chops. By using the “isopachic triangle” method, the sequence of the development of the roof surfaces of horizons on the constructed structural maps and isopachite maps is determined.

Keywords
isopachic triangle, structural maps, isopachite maps, carboniferous deposits, spatial analysis

Fighting the negative impact of mechanical impurities with simultaneous separate operation

Meshcheryakov A.A., Shagitov R.Z., Slivka P.I.

DOI: 10.24412/2076-6785-2023-1-21-26

Abstract
The article discusses the complicating factors that occur during the operation of various types of installations for simultaneous separate operation (SSE), as well as ways to protect equipment for SSE from the negative impact of complicating factors.

Materials and methods
Analytical database of equipment operation at the same time separate operation, design documentation of the mixer filter and brush filter, results of field tests, conditional classifier of systems at the same time separate operation.

Keywords
complicating factors, mechanical impurities, simultaneous separate operation, simultaneous separate production, expert support team, filter liquid mixer, brush filter

Conditions of sedimentation of deposits of the redkolesnaya formation of the Irkineevo-Chadobets rift zone

Postnikova O.V., Izyurova E.S., Izyurov A.D., Kuchnov D.S.

DOI: 10.24412/2076-6785-2023-1-14-20

Abstract
The aim of this work was to establish the conditions of sedimentation of the vendian redkolesnaya formation within the Irkineevo-Chadobets rift zone in the southwest of the Siberian platform. The work is based on 184 thin section samples and 240 meters of core material from deep drilling wells of the Irkineevo-Chadobets rift zone, as well as stock material and the results of geophysical, lithological, petrophysical studies. According to the results of lithological and cyclostratigraphic studies, three sedimentary cyclites are distinguished in the volume of the redkolesnaya formation, having a transgressive structure, which is expressed in the change of sandy and siltstone rocks to sulfate-carbonate deposits in the roofing parts of the cyclites. The mineral composition contains fragments of quartz, feldspars, quartzites, and clay shales, the source of which was the metamorphic rocks of the Yenisei ridge, as well as igneous rocks of the Baikal anteclise arch. The latter were the main source for the deposits of the redkolesnaya formation. Based on the results of lithofacial analysis, it was revealed that the formation of deposits of the redkolesnaya formation occurred under the conditions of fluvial relief forms (a time-migrating cone) and salt marches in the zones of the supratidal, intertidal and subtidal, during the development of the Vendian transgression of the marine basin in the southwest of the Siberian Platform.

Materials and methods
The work is based on 240 meters of core material from deep drilling wells of the Irkineevo-Chadobets rift zone e, as well as stock material and the results of geophysical, lithological, petrophysical studies. The results of the study of rocks in 184 thin sections, on an electron microscope and an X-ray diffractometer were used. Experimental studies were carried out using a polarizing microscope Axio Imager A2m Carl Zeiss and a stereomicroscope Carl Zeiss Micro Imaging GmbH; studies of the mineral composition of lithotypes, as well as the elemental composition of rocks, were performed using an energydispersive spectrometer on a scanning electron microscope (SEM) JEOL JSM-6610LV
with an attachment for microanalysis OXFORD INSTRUMENTS IE350-IW500-HKL; The study of the mineral composition of the rocks was carried out using a RIGAKU (XRD) SmartLab X-ray diffractometer.

Keywords
redkolesnaya formation, vendian, Irkineevo-Chadobets rift zone, Siberian platform, sedimentation conditions

Intricate hydrocarbon deposits in the Lower Permian sediments of the southeastern slope of the Russian Platform

Utoplennikov V.K., Drabkina A.D.

DOI: 10.24412/2076-6785-2022-3-41-25

Abstract
Drilling materials, geological and geophysical studies of the Lower Permian sediments indicate that the southeastern slope of the East European platform within the Volga-Ural oil of the gas-bearing province is highly promising for the identification and involvement in the development of new large oil resources in the deposits of the upper part of the section, adjacent to the Lower Permian rifogenic-carbonate-sulphate fluorine.

Materials and methods
A comprehensive analysis of structural constructions based on the results of drilling of structural prospecting and exploration wells has been carried out. Studies of geological-lithological and petrophysical factors of localization of oil and gas accumulations in the Lower Permian reservoirs have been carried out.

Keywords
reef formation, oil and gas-bearing province, facial composition, fluid stops

Algorithm of separation of production and injection data by sequences, taking into account field geophysical data and hydraulic fracturing (by the example of AV1(3)-AV2-3 object of the Samotlor field)

Shkitin A.A., Mityakin I.B., Arkhipova E.L., Abdrakhimov R.I., Deriglazov D.N., Pisarev D.Yu.

DOI: 10.24412/2076-6785-2022-3-34-38

Abstract
The purpose of this work is to use a proprietary digital tool to create a monthly process for separating historical cumulative production and injection by the selected sequences of the development object, taking into account actual field geophysical survey data and hydraulic fracturing to find zones of localization of current recoverable reserves.

Materials and methods
The authors of the work performed a detailed analysis of the geological structure and degree of formation opening, clarified the division of the target object AV1(3)-AV2-3 into 4 and constructed author’s maps of the sequences. An algorithm was developed to divide production and injection in the target by sequence, using field geophysical survey data,
hydraulic fracturing, perforations and inclinometry, taking into account gyroscopes, conductivity (KH) joint objects, well log interpretation data and author’s maps. The algorithms were implemented as a program for separating indicators by stratas on the basis of monthly production and injection data (Monthly Production Report). An additional database for disaggregated objects was formed (database on sequences), where the detailed control of development and selection of candidates for geological and engineering operations is performed, as well as the formation of the research work program.

Keywords
detailed section of the development object by sequences; production and injection separation algorithm; accounting of the digitized field geophysical survey data; accounting of the digitized hydraulic fracturing reports; clarification of the residual oil reserves localization; well intervention planning; management and control of the development

Assessment of prospects for development of reservoir AV1 1-2 on the basis of the refined petrophysical model

Agishev E.R., Zhdanov L.M., Ramadanov A.V., Ramadanova D.A., Voronina A.N., Kararova A.Z.

DOI: 10.24412/2076-6785-2022-3-29-33

Abstract
In this paper, the authors refine petrophysical models of sandy-silty-clayey rocks of the AV1 1-2 horizon with “ryabchik” texture. The work is based on new logging and coring data in intervals of weakly permeable strongly clayey reservoirs. These studies updated the current understanding of the petrophysical parameters of the reservoir and increased the technical and economic potential of involving it in production.

Materials and methods
Detailed description and studies of core material, geophysical well logging. Statistical processing of core and logging data, lithofacies analysis, construction of core-logging dependencies, geological modeling.

Keywords
complicated low-permeability reservoir, lithologic-facial model, petrophysical model, initial geological reserves

Geological setting and petrophysical modeling features of Ust-Kut Carbonate Reservoirs (Nepa-Botuoba Petroleum Province)

Distanova L.R., Kovalenko E.V., Arzhilovskaya N.N., Maksimova E.N., Nedelko O.V., Chertina K.N.

DOI: 10.24412/2076-6785-2022-3-22-26

Abstract
This article contains detailed geological description and petrophysical modeling features of productive deposits in the Ust-Kutsky horizon of the North Danilovskoye Field of the Nepa-Botuoba Petroleum Province (NBP). The sediments have rather complex vertical distribution and variable reservoir properties. A complex of laboratory studies has been made and sedimentation-capacitive model of the pore space was developed according to the fact of the specific composition of sediments and facies heterogeneity. The presented approaches open up opportunities for the highest reservoir properties zones discovering.

Materials and methods
Materials: macro and micro core descriptions, laboratory researches, Interpretation of facies well logs correlation, well correlation, facies correlation, mapping, petrophysical modeling, petrophysical functions analysis.

Keywords
organogenic buildup, the Lower Ust-Kutsky horizon, sublittoral, petrophysical modeling, sedimentation-capacitive model

Modeling experience of low-permeability reservoirs the case of license block of the Priobskoe field

Petruk A.C., Rodionova I.I., Mukhametov A.R., Galeev E.R., Iskevich I.G., Fazylov D.S., Mummer P.S.

DOI: 10.24412/2076-6785-2022-3-18-20

Abstract
The article presents an approach to modeling low-permeability, low-dissected zones of deep-water fan facies on the example of one of the licensed areas of the Priobskoye field, based on a significant reduction in correlation radii. Drilling of many horizontal wells (HWs) in the area under consideration made it possible to measure the average size of sand bodies. For a more reliable result, horizontal wells (HWs) were taken at an enormous distance from each other and from different parts of the field. The trajectory of the horizontal part of the wells penetrates parallel to the structural surfaces. In the study’s course, it is deemed that the average size of the bodies is 220 m. At the stage of hydrodynamic modeling,
a better convergence of well productivity dynamics was obtained than with the standard approach to building a model.

Materials and methods
Based on the results gamma ray from many densely spaced horizontal wells, work has been done to measure the average size of sand body lengths. Based on the goat values, the probability field was by investigated in variogram analysis at a shorter distance. Taking into account the new correlation radii and the nature of the distribution of reservoir properties in the distal part of the turbidite complex, a model is constructed that is close to real geology. Calculations of the hydrodynamic model were performed, the best convergence of well
productivity dynamics was obtained.

Keywords
horizontal wells, variogram analysis, convergence, well productivity, low-permeability reservoir, hard-to-recover reserves, geological modeling, hydrodynamic modeling

Work out in detail of fammenian carbonates geology at platform Bashkortostan in connection their new oil and gas perspectives

Lozin E.V.

DOI: 10.24412/2076-6785-2022-3-11-15

Abstract
In article the data according to above mention problem are published. The Fammenian carbonate deflections take part of upper Devonian-Tournaisian oil-gas complex among seven oil-gas complexes at platform Bashkortostan. Its deflections are bedding on thin Fran sediments and introduced, by essence, basic deflections of Paleozoic carbonate thick series. Depressions of Kamsko-Kinel System (KKS) and two paleo-shelf (Bashkir and Tatar) define tectonic framework of Fammenian carbonate. Analysis was given on date of three representative oil fields. Most conclusions are following. Dynamic regime of sedimentation had different mechanism into separate zones to KKS depressions. At Western part of contemporary Bashkir arch and contemporary Birsk saddle large barrier reefs and companying local reefs are not productivity. But above its local structures into Terrigenous
Low Carbon (TTLC) contain unique, large, middle and little oil fields. It means that Fammenian plan controlled upper structure plans in territory KKS depressions. In other parts of KKS depression dynamic regime of sedimentation, opportunity into South-Western party of Aktanysh-Chishma Depression, the ring sandstone TTLC formations are formed around local Fammenian-Tournal reef. The new, unknown up to oil fields ÒÒLC are contains into its. Above mention predication don’t corresponds to Bashkir and Tatar paleo-shelfs as a one’s organic buildings (OB) have minimal volume and amplitude, and tectonic regime corresponded to normal sedimentary. Oil-gas deposits on paleo-shelfs are small.
Further oil-gas perspective will associated with: zones of increase thickness Fammenian carbonates on north-west – particularly in regions of cross Paleozoic sedimentary with foundation steps. Than the perspectives will connection with local regions of “sault tectonic” into Salmuysh
depression and with prognostication zones anomaly low sheet pressure.

Materials and methods
The main emphasis of the work is a geological paradox: at the base of carbonate bodies, which are of enormous size (barrier reefs) and, accordingly, the expected large capacity for the generation and creation of hydrocarbons, there are no signs of a creative “kitchen” for the reactions of hydrocarbon synthesis (or other mechanism of hydrocarbon
origin).

Keywords
fammenian, geological cross section, depression, oil-gas deposit, paleo-shelf

Modeling experience of low-permeability reservoirs the case of license block of the Priobskoe field

Petruk A.A., Rodionova I.I., Mukhametov A.R., Galeev E.R., Iskevich I.G., Fazylov D.S., Mummer P.S.

DOI: 10.24412/2076-6785-2022-2-45-50

Abstract
The article presents an approach to modeling low-permeability, low-dissected zones of deep-water fan facies on the example of one of the licensed areas of the Priobskoye field, based on a significant reduction in correlation radii. Drilling of many horizontal wells (HWs) in the area under consideration made it possible to measure the average size of sand bodies. For a more reliable result, horizontal wells (HWs) were taken at an enormous distance from each other and from different parts of the field. The trajectory of the horizontal part of the wells penetrates parallel to the structural surfaces. In the study’s course, it is deemed that the average size of the bodies is 220 m.

Materials and methods
Based on the results gamma ray from many densely spaced horizontal wells, work has been done to measure the average size of sand body lengths. Based on the goat values, the probability field was by investigated in variogram analysis at a shorter distance. Considering the new correlation radii and the nature of the distribution of reservoir properties in the distal part of the turbidite complex, a model is constructed.

Keywords
horizontal wells, variogram analysis, convergence, well productivity, low-permeability reservoir, hard-to-recover reserves