Articles

Geology

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 authors 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 authors 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 studys 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 LC are contains into its. Above mention predication dont corresponds to Bashkir and Tatar paleo-shelfs as a ones 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 studys 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

The results of a comprehensive study of an unconventional fractured cavernous reservoir on the example of one of the deposits of the Krasnoleninsky district (justification of potentially productive intervals and fracture zones)

Grishchenko M.A., Smyshlyaeva M.D., Avramenko E.B.

DOI: 10.24412/2076-6785-2022-2-39-43

Abstract
This article continues the cycle of scientific publications of NK Rosneft PJSC devoted to the comprehensive study of the Bazhen-Abalaksky complex (BAC) on the territory of the Krasnoleninsky arch. The article presents the main results of analysis of productivity of the studied section and development of fracture zones at the test site of one of the fields of Krasnoleninsky district.

Materials and methods
Materials. Complex laboratory studies were carried out on the core of 11 wells: lithological-mineralogical, sedimentological, biostratigraphic, geochemical, pyrolytic, geomechanical, mercury porometry and microtomographic studies, full-size core fracture studied. Methods. A 1D fracture model and a detailed geological model of the double medium of the BAC strata were constructed. Analysis of productivity of the studied section and development of fracture zones was performed.

Keywords
Bazheno-Abalak complex, crack model, double medium, 3D model, section productivity

Upper Devonian carbonate deposits seals composition Volga-Ural region and the method of their identification based on well logging data

Nigmatzyanova A.M., Mirnov R.V., Burikova T.V., Bakirov R.D., Shavaliev V.I.

DOI: 10.24412/2076-6785-2022-2-31-36

Abstract
The Upper Devonian deposits of the Volga-Ural oil and gas province are promising for oil exploration. An important factor in predicting the development of traps is the presence or absence of seal rocks. The relevance of the topic is the ability to predict the distribution of seal rocks using well logging methods and, consequently, increase the efficiency of exploration work. The article presents a technique for separating fluid seals from well log data, based on lithological study of the core and confirmed by test results. As a result of the analysis, boundary values were obtained for various geophysical parameters, which make it possible to distinguish impermeable strata.

Materials and methods
The technique was created on the basis of data from 15 deposits of the Volga-Ural region, more than 500 linear meters were studied core from non-reservoir intervals. Wells with a direct sign of the presence of a seal were taken as reference: where, according to the results of testing, below the interval of development of the seal, oil was obtained,
and above formation water. Lithological differentiation was carried out on the basis of logging methods, the thickness was determined, and the main parameters were calculated.

Keywords
seals, Upper Devonian deposits of the Volga-Ural oil and gas province, geophysical parameters, limestones

Investigation of the oil and gas potential of megareservoirs in difficult geological and climatic conditions

Shuster V.L.

DOI: 10.24412/2076-6785-2022-2-26-29

Abstract
Along with the exploration and development of well-known oil and gas fields in Russia, prospecting and exploration work has begun and continues in regions that are difficult in terms of geological and climatic conditions (Arctic seas shelf, deep horizons). The article examines the conditions for the effective development of oil and gas resources in new areas of exploration. One of the most important factors of profitability of projects is the discovery of significant reserves of deposits, as a rule, confined to megareservaries. Other geological
parameters affecting the oil and gas potential of megareservoirs have also been investigated.

Materials and methods
Published actual data on 14 largest oil and gas fields in the world and in Russia were used. The relationship between the reserves of oil and gas accumulations and the geological parameters of megareservoirs, types
of traps.

Keywords
megareservoir, large oil and gas fields, Russian Arctic shelf, new facilities

Determination of features of the geological structure of Lower Aptian formation of West Siberian on basis of refined lithological-facial model of reservoir AV1 1-2

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

DOI: 10.24412/2076-6785-2022-2-20-23

Abstract
In this paper, the authors refine the geological-facial model of sandy-silty-clayey rocks of the AV1 1-2 horizon with ryabchik texture. The work is based on new coring data in intervals of weakly permeable strongly clayey reservoirs. The conducted studies updated current understanding of lithofacies features of the reservoir. Based on results of the presented analysis, an own petrophysical reservoir model is based, which makes it possible to increase detail of identification productive intervals and establish petrophysical dependencies.

Materials and methods
Detailed description and studies of core material, geophysical well logging. Statistical processing of core data, lithofacies analysis, well correlation.

Keywords
complicated low-permeability reservoir, lithologic-facial model, ryabchik reservoir, hard-to-recover reserves

Identification and forecasting of promising zones of the VK1 vikulovskaya suite formation of the Ai-Tor uplift in order to increase the efficiency of production drilling of wells

Ilzit E.V.

DOI: 10.24412/2076-6785-2022-2-14-18

Abstract
The value of the work lies in the developed methodology for predicting zones with improved reservoir properties of the VK1 formation within the Kamenny (western part) license area of the Krasnoleninskoye oil and gas condensate field. The development of this area is complicated by the presence of extensive oil-water zones, low oil saturation, average reservoir properties, as well as high heterogeneity of the reservoir, the presence of an incised valley and tectonic disturbances. Thus, the forecasting of promising areas is of great practical importance, since the economic efficiency of the well stock, the drilling of wells along the reservoir, the change in drilling goals, the planning and success of geological
and technical measures depend on the prediction.

Materials and methods
Materials: the initial GIS and RIGIS data for 156 production wells were used as input data, surface characteristics of parameters calculated from amplitude cubes in two processing variants involving sedimentological description of the core of 11 exploration wells. Methods: complex analysis of geological and geophysical information, dynamic analysis, construction of spectral decomposition maps, sedimentological description of the core with analysis of sedimentation conditions, search and selection of quantitative criteria for identifying
promising zones.

Keywords
reservoir, improved reservoir properties, coastal-marine conditions of sedimentation, distribution channels, effective thicknesses, reservoir properties, oil saturation coefficient, Ai-Tor uplift, Krasnoleninsky arch

Adapting the technology for the construction of TAML-1 level multilateral wells at the Novoportovskoye field for separate production accounting for each reservoir

Samigullin L.R., Alekseev A.V., Zimoglyad M.B., Nagovitsyn M.V., Vasechkin D.A., Bydzan A.Yu., Bolshakov V.V., Drobot A.V.

DOI: 10.24412/2076-6785-2022-1-36-42

Abstract
The Novoportovskoye field is characterised by a mainly complex geological structure and the presence of remaining reserves. The situation is further aggravated by significant oil reserves occurring right under massive gas caps. To make HC recovery profitable in such geological settings, new technologies are required. This paper provides an insight into the case of creating a multilateral well based on a new TAML-1 level completion solution utilising the properties of the impermeable top of one bed and the dynamic quantum PLT to measure production from each formation separately in accordance with existing regulations.

Materials and methods
Materials: electronic data base of technical library with depictions of the Novoportovkoye field, its geological structure and filtration-and-volume characteristics of producing formations.
Methods: graphical representations of wellbore performance dynamics, laboratory analysis of formation fluid sample sets description.

Keywords
multilateral wells, well construction technologies, TAML, dynamic marker-based monitoring, inflow profile, separate production accounting

Geochemical features of fluids in reservoirs Volga-Ural region as a result of migration processes

Punanova S.A., Samoilova A.V.

DOI: 10.24412/2076-6785-2022-1-30-34

Abstract
The article presents the characteristics of fluid hydrocarbon (HC) accumulations of the Volga-Ural oil and gas basin (OGB) with the identification of types of oils of different ages. The influence of migration processes during the formation of fluid reservoirs in the sedimentary cover of the basin and, in this connection, the possibility of predicting the properties of fluids in non-anticlinal traps of the developed oil and gas bearing complexes (OGC) in the region are emphasized.

Materials and methods
Analytical database of properties of oils from oil and gas complexes of different ages in the Volga-Ural oil and gas field, including data on the content of trace elements in them.
Comparison of the parameters of the oil and gas content of the complex according to geochemical data, a graphical representation of the dependences of the density and physicochemical properties of oils on their tectonic confinement and the age of oil-bearing deposits.

Keywords
fluids, oil and gas complexes, oil, non-anticlinal traps, migration processes, trace elements, physical and chemical properties of oils

Genetic void types and their distribution regularities in carbonate reservoirs of Timan-Pechora province

Postnikov A.V., Olenova K.Yu., Sivalneva O.V., Kozionov A.E., Kazimirov E.T., Putilov I.S., Potekhin D.V., Saetgaraev A.D.

DOI: 10.24412/2076-6785-2022-1-22-28

Abstract
One of the main problems of petroleum geology and development is research and modeling of void space heterogeneity and its properties in the reservoir rocks. Carbonate deposits, as a rule, contain of reservoir rocks which have highly intricate structure and distribution of pore space. Their formation is influenced by many factors: tectonic processes, paleogeographic environments, depositional environments, evolution of biological communities (biocenoses), and the post-sedimentary processes. The article discusses the regional factors of the Timan-Pechora province (TPP) for three large oil and gas complexes: the Silurian-Lower Devonian, Upper Devonian-Tournaisian and Permian-Carboniferous; highlights the results of the characteristics and comparative analysis of the void space in various structural components of rocks; identification of the spatial distribution patterns and properties of the void space.

Materials and methods
In this study, were research over 1000 core plates in 15 wells from 9 fields. Associated with them petrophysical cylinders and thin sections were analyzed by using optical and electron microscopy, computed X-ray tomography and image analysis of void space (in stained thin sections). The studies of petrophysical cylinders were carried out at LUKOIL-Engineering LLC. The rest of the listed studies were carried out at the Department of Lithology at the Gubkin RSU of oil and gas.

Keywords
carbonate reservoir, reservoir rocks, voids, wettability, Timan-Pechora province, paleosoic

The results of a comprehensive study of an unconventional fractured cavernous reservoir on the example of one of the deposits of the Krasnoleninsky district (substantiation of basic model of collector structure)

Grishchenko M.A., Smyshlyaeva M.D., Avramenko E.B.

DOI: 10.24412/2076-6785-2022-1-15-20

Abstract
This article continues the cycle of scientific publications of NK Rosneft PJSC devoted to the comprehensive study of the bazhen-abalaksky complex (BAC) on the territory of the Krasnoleninsky arch. The article presents the main results of complex laboratory core studies and substantiation of the principal model of reservoir structure in the unconventional fractured cavernous reservoir of the BAC, which served as the
basis for localization of potentially productive zones at the test site of one of the deposits of the Krasnoleninsky district.

Materials and methods
Materials: Complex laboratory studies were carried out on the core of 11 wells: lithological-mineralogical, sedimentological, biostratigraphic, geochemical, pyrolytic, geomechanical, mercury porometry and microtomographic studies, determination of filtration and capacitance properties. Methods: A mineral-component and petrophysical model of the
bazheno-abalak complex has been created.

Keywords
bazheno-abalak complex, a mineral-component model

Integration of NMR relaxometry data and electrometric studies on the example of reservoir rocks of deposits of the Timan-Pechora oil and gas province

Rogozin A.A., Ignateva T.S., Churkov A.V.

DOI: 10.24412/2076-6785-2021-6-62-66

Abstract
The specific pore surface and core permeability are one of the most important parameters in the study of reservoir rocks. At the same time, their determination by standard methods, such as capillarimetry and direct filtration studies, can be accompanied by the destruction of samples and take a long time. This article discusses the informative value of the NMR-relaxometry method for studying these parameters, as well as the applicability of a comprehensive analysis of the filtration-capacitance properties and properties of the pore space of rocks using electrometry data of saturated core samples. As will be shown below, combining the data of various methods allows us to determine for each lithotype such an NMR
parameter as surface relaxivity. The article presents a calculation and comparative analysis of the values of the specific pore surface determined by different methods;
the applicability of some empirical and semi-empirical methods for calculating permeability is shown; relaxation constants for various lithotypes of reservoir rocks of the Timan-Pechora oil and gas province are determined.


Materials and methods
Laboratory studies by NMR-relaxometry, permeometry, determination of UES of rocks.

Keywords
nuclear magnetic resonance, relaxability, porosity, permeability, relaxation times, specific pore surface, pore tortuosity, electrical properties

Geological structure and oil and gas potential of the Yuryakha horizon of Srednebotuobinskoye field

Olenich P.A., Bukharova I.A., Novikova M.S., Khorolsky G.O., Chirgun A.S.

DOI: 10.24412/2076-6785-2021-6-58-61

Abstract
The study is based on generalizing the results of exploration and development drilling, the results of core studies, as well as seismic data. To define the reservoir distribution patterns, the Yuryakha horizon was correlated within the Srednebotuobinsky field and the results were compared with other fields of the Nepa-Botuobinsky anteclise. The features of the geological structure of the Yuryakha horizon were studied, and the resources were estimated.

Materials and methods
Materials: well logging data, core study results, seismic data interpretation results on the Srednebotuobinskoye field. Methods: reservoir correlation, petrophysical modeling, seismic
analysis.


Keywords
East Siberia, Nepa-Botuobinskaya anteclise, Srednebotuobinskoye field, Yuryakha horizon, resource potential, seismic exploration, hard-to-recover reserves