A. Tchistiakov, Kseniia O. Zudina, Aigul R. Davletshina, E. Shvalyuk, V. Baranov
The proposed method of predicting spatial distribution of leaching zones in carbonate reservoirs includes integrated interpretation of well logging data, including electrical microimages (Formation MicroImager – FMI), together with analysis of lithofacies within depositional cycles. Based on the comparison of FMI data with results of lithological and petrophysical studies of the core, an atlas of diagenetic porosity images for the studied formation was developed. Choquette and Pray international classification was used for pore typing. Applying the developed atlas to FMI logs, karstification zones were identified and classified in reference wells. In wells, where only standard well loggings was performed, karstification zones were identified using a developed decision tree. Sedimentological and sequence stratigraphic analysis made it possible to identify sedimentation cycles and to correlate the main lithofacies within the target reservoir. It was established that microbial and shallow facies form the most productive part of the reservoir. These facies with initially high primary porosity were subjected to the most intensive karstification along sequence stratigraphic boundaries due to subaerial exposure. The established relationships between leaching zones, lithofacies, and sequence-stratigraphic boundaries made it possible to carry out inter-well correlation of karstified intervals. The correlation will allow construction of leaching zones maps, that will be further applied for geological modeling.
{"title":"Prognosis of leaching zones distribution in carbonate reservoirs","authors":"A. Tchistiakov, Kseniia O. Zudina, Aigul R. Davletshina, E. Shvalyuk, V. Baranov","doi":"10.18599/grs.2022.4.10","DOIUrl":"https://doi.org/10.18599/grs.2022.4.10","url":null,"abstract":"The proposed method of predicting spatial distribution of leaching zones in carbonate reservoirs includes integrated interpretation of well logging data, including electrical microimages (Formation MicroImager – FMI), together with analysis of lithofacies within depositional cycles. Based on the comparison of FMI data with results of lithological and petrophysical studies of the core, an atlas of diagenetic porosity images for the studied formation was developed. Choquette and Pray international classification was used for pore typing. Applying the developed atlas to FMI logs, karstification zones were identified and classified in reference wells. In wells, where only standard well loggings was performed, karstification zones were identified using a developed decision tree. Sedimentological and sequence stratigraphic analysis made it possible to identify sedimentation cycles and to correlate the main lithofacies within the target reservoir. It was established that microbial and shallow facies form the most productive part of the reservoir. These facies with initially high primary porosity were subjected to the most intensive karstification along sequence stratigraphic boundaries due to subaerial exposure. The established relationships between leaching zones, lithofacies, and sequence-stratigraphic boundaries made it possible to carry out inter-well correlation of karstified intervals. The correlation will allow construction of leaching zones maps, that will be further applied for geological modeling.","PeriodicalId":43752,"journal":{"name":"Georesursy","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48012862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Lutfullin, E. M. Abusalimov, A. E. Folomeev, A. R. Khatmullin, A. Sharifullin, M. R. Sitdikov
Nowadays, oil fields on the territory of the Republic of Tatarstan are developed with application of systems for reservoir pressure maintenance, involving injection of large volumes of water into the formation. Efficiency of waterflooding depends on the quality of the injected agent, and, despite the use of various technologies of preparation and treatment of injected water, with the lapse of time critical matrix porosity and permeability inevitably decreases. In this work the main sources of injection wells critical matrix clogging are considered: mechanical impurities, oil products and scales formation, and the results of the component composition analysis of deposits from cluster pumping stations are given. Using the Oddo-Thomson methodology, it is revealed that injected water is prone to calcite and barite deposition at bottomhole conditions. Physicochemical and core-flooding study of several reagents for removing colmatants: acid compositions, hydrocarbon solvents and complexing agents were carried out and their optimal formulations were determined. The matrix treatment technology, including the sequential injection of compositions based on hydrochloric and mud acids, was substantiated. An algorithm for calculating the optimal reagent volume has been developed on the basis of research data on the mineralogical composition of mechanical impurities and ionic composition of injected water. Four types of matrix treatment technologies were determined for the conditions of injection wells at the Romashkinskoye oil field Devonian formation, taking into account the composition of colmatant, and acid treatment designs were developed.
{"title":"Complex matrix treatment technologies selection and adaptation for the injection wells of the Republic of Tatarstan oilfields","authors":"A. Lutfullin, E. M. Abusalimov, A. E. Folomeev, A. R. Khatmullin, A. Sharifullin, M. R. Sitdikov","doi":"10.18599/grs.2022.4.8","DOIUrl":"https://doi.org/10.18599/grs.2022.4.8","url":null,"abstract":"Nowadays, oil fields on the territory of the Republic of Tatarstan are developed with application of systems for reservoir pressure maintenance, involving injection of large volumes of water into the formation. Efficiency of waterflooding depends on the quality of the injected agent, and, despite the use of various technologies of preparation and treatment of injected water, with the lapse of time critical matrix porosity and permeability inevitably decreases. In this work the main sources of injection wells critical matrix clogging are considered: mechanical impurities, oil products and scales formation, and the results of the component composition analysis of deposits from cluster pumping stations are given. Using the Oddo-Thomson methodology, it is revealed that injected water is prone to calcite and barite deposition at bottomhole conditions. Physicochemical and core-flooding study of several reagents for removing colmatants: acid compositions, hydrocarbon solvents and complexing agents were carried out and their optimal formulations were determined. The matrix treatment technology, including the sequential injection of compositions based on hydrochloric and mud acids, was substantiated. An algorithm for calculating the optimal reagent volume has been developed on the basis of research data on the mineralogical composition of mechanical impurities and ionic composition of injected water. Four types of matrix treatment technologies were determined for the conditions of injection wells at the Romashkinskoye oil field Devonian formation, taking into account the composition of colmatant, and acid treatment designs were developed.","PeriodicalId":43752,"journal":{"name":"Georesursy","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49109384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This work is devoted to development of an automatic algorithm for determining the velocity model from the data of the field seismic profile. First of all total energy of received signal and the positions of the first arrivals of reflected waves has to be determined. The traces sort by common depth point and the spectra of possible velocities determine at each point of the trace and each assembly of the common deep point. The procedure is fully automated and as a result, instead of about 150 points of manual processing, 4 million points are obtained on the test profile. The values of chosen effective speeds correspond not only to existing criteria for their determination, but also to requirement of smoothness in first derivative. This makes it possible to determine reliable interval velocity profile at each track point and each collection of the common depth point. Speed determination accuracy in the range of 10-50 m/s. After recalculating the time profile into a depth profile, it becomes possible to obtain high-resolution and detailed model of the velocity structure of the geological profile during migration transformations. An iteration process refines the calculations obtained by geologists and geophysicists in order to obtain consistent and consistent results.
{"title":"Development of a numerical algorithm for solving the problem of processing and determining the basic velocity model","authors":"A. E. Shumeyko, Vadim A. Tsygankov","doi":"10.18599/grs.2022.4.12","DOIUrl":"https://doi.org/10.18599/grs.2022.4.12","url":null,"abstract":"This work is devoted to development of an automatic algorithm for determining the velocity model from the data of the field seismic profile. First of all total energy of received signal and the positions of the first arrivals of reflected waves has to be determined. The traces sort by common depth point and the spectra of possible velocities determine at each point of the trace and each assembly of the common deep point. The procedure is fully automated and as a result, instead of about 150 points of manual processing, 4 million points are obtained on the test profile. The values of chosen effective speeds correspond not only to existing criteria for their determination, but also to requirement of smoothness in first derivative. This makes it possible to determine reliable interval velocity profile at each track point and each collection of the common depth point. Speed determination accuracy in the range of 10-50 m/s. After recalculating the time profile into a depth profile, it becomes possible to obtain high-resolution and detailed model of the velocity structure of the geological profile during migration transformations. An iteration process refines the calculations obtained by geologists and geophysicists in order to obtain consistent and consistent results.","PeriodicalId":43752,"journal":{"name":"Georesursy","volume":"38 14","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41309295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Kolchugin, E. Ziganshin, V. Morozov, E. S. Bystrov, E. Korolev, Salavat I. Gilfanov
The method of acid hydraulic fracturing has been actively used in recent years, for the deposits of the Vereysky horizon of the Moscowian strata in the south-east of Tatarstan. Design development and the use of hydraulic fracturing requires full-fledged studies of the geomechanical characteristics of rocks, including the prediction of the propagation of emerging fractures. It is considered the main geomechanical characteristics for reservoir rocks and dense rocks involved in the structure of the sections, on the example of the study of polyfacial reservoirs of the Vereysky horizon of the Ivinskoye oil field. It was revealed that the carbonate reservoir rocks of the middle and upper parts of the Vereysky horizon (C2vr3 and C2vr5) have the least strength properties and a greater susceptibility to fracturing. More durable were sandstones of the upper part of the horizon, marls and mudstones of the middle and upper parts of the horizon, as well as mudstone and dense packstone, typical for the lower part of the Vereysky horizon. The presented data can be valid for most of the sections of the Vereysky horizon of the southeast of Tatarstan and are used for the choice of optimal solutions when applying the hydraulic fracturing technology.
{"title":"Geomechanical and lithological characteristics of the Vereysky horizon in the Middle Carboniferous for prediction of hydraulic fracturing technology, on the example of the Ivinskoye field in the South-East of Tatarstan","authors":"A. Kolchugin, E. Ziganshin, V. Morozov, E. S. Bystrov, E. Korolev, Salavat I. Gilfanov","doi":"10.18599/grs.2022.4.5","DOIUrl":"https://doi.org/10.18599/grs.2022.4.5","url":null,"abstract":"The method of acid hydraulic fracturing has been actively used in recent years, for the deposits of the Vereysky horizon of the Moscowian strata in the south-east of Tatarstan. Design development and the use of hydraulic fracturing requires full-fledged studies of the geomechanical characteristics of rocks, including the prediction of the propagation of emerging fractures. It is considered the main geomechanical characteristics for reservoir rocks and dense rocks involved in the structure of the sections, on the example of the study of polyfacial reservoirs of the Vereysky horizon of the Ivinskoye oil field. It was revealed that the carbonate reservoir rocks of the middle and upper parts of the Vereysky horizon (C2vr3 and C2vr5) have the least strength properties and a greater susceptibility to fracturing. More durable were sandstones of the upper part of the horizon, marls and mudstones of the middle and upper parts of the horizon, as well as mudstone and dense packstone, typical for the lower part of the Vereysky horizon. The presented data can be valid for most of the sections of the Vereysky horizon of the southeast of Tatarstan and are used for the choice of optimal solutions when applying the hydraulic fracturing technology.","PeriodicalId":43752,"journal":{"name":"Georesursy","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47119306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. Ovchinnikov, Y. Kotenev, Shamil Kh. Sultanov, A. V. Chibisov, D. Chudinova
This paper presents the results of geological and production analysis of development and reserves of the pilot area using the results of dynamic marker monitoring of horizontal wellbores of production wells using high-precision indicators. As part of the research, the geological structure of the reservoir section was updated, which includes a lithological and facial analysis and geological and hydrodynamic simulation of the reservoir. The energy state of the reservoir was analyzed and the efficiency of the waterflood system was evaluated using dynamic data analysis and correlation analysis. The reasons for changes in the dynamics of inflow profiles over time have been analyzed. By the example of the pilot area the decision-making algorithm for adjusting the process of hydrocarbon reserves extraction, based on the analysis of the relevant geological and technical information, obtained during the long-term dynamic marker monitoring of the horizontal wells operation, has been implemented. A set of recommendations has been developed, which makes it possible to achieve stable dynamics of development indicators, to increase the coefficients of coverage by displacement in the area and the reservoir section, to involve previously undrained areas of oil reserves in the development. The results of the analysis of the efficiency of the implemented geological and technological measures are presented.
{"title":"Regulation of hydrocarbon production process based on dynamic tracer monitoring of horizontal well inflow profile","authors":"K. Ovchinnikov, Y. Kotenev, Shamil Kh. Sultanov, A. V. Chibisov, D. Chudinova","doi":"10.18599/grs.2022.4.11","DOIUrl":"https://doi.org/10.18599/grs.2022.4.11","url":null,"abstract":"This paper presents the results of geological and production analysis of development and reserves of the pilot area using the results of dynamic marker monitoring of horizontal wellbores of production wells using high-precision indicators. As part of the research, the geological structure of the reservoir section was updated, which includes a lithological and facial analysis and geological and hydrodynamic simulation of the reservoir. The energy state of the reservoir was analyzed and the efficiency of the waterflood system was evaluated using dynamic data analysis and correlation analysis. The reasons for changes in the dynamics of inflow profiles over time have been analyzed. By the example of the pilot area the decision-making algorithm for adjusting the process of hydrocarbon reserves extraction, based on the analysis of the relevant geological and technical information, obtained during the long-term dynamic marker monitoring of the horizontal wells operation, has been implemented. A set of recommendations has been developed, which makes it possible to achieve stable dynamics of development indicators, to increase the coefficients of coverage by displacement in the area and the reservoir section, to involve previously undrained areas of oil reserves in the development. The results of the analysis of the efficiency of the implemented geological and technological measures are presented.","PeriodicalId":43752,"journal":{"name":"Georesursy","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47281565","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zalina R. Saptarova, Alexander A. Mamonov, S. Usmanov, A. Lutfullin, V. Sudakov, M. Shipaeva, A. Shakirov
This article is devoted to the review of one of the currently relevant methods of enhanced oil recovery – low-salinity waterflooding (LSW) – on the example of terrigenous Tulian, Bobrikovian and Devonian reservoirs of the Tatarstan Republic fields. The first part of review contains information about the key processes underlying this method, such as swelling and migration of clay particles and wettability alteration, as well as the mechanisms that explain these processes, which include cation exchange, multicomponent ion exchange, electric double layer expansion, etc. Their understanding, in turn, contributes to the identification of the main factors, the presence or absence of which at the field allows us to give a preliminary assessment of LSW application. There are main factors: the presence of clay particles, a significant content of Ca2+ and Mg2+ ions, as well as multivalent ions in formation water, low formation permeability, reduced oil viscosity, an increased content of acidic and especially basic components in oil and, as a result, a hydrophobic type of initial rock wettability. Then, examples of using the method in other fields are given and the results of laboratory studies, including the measurement of the contact angle, core flooding experiments, are briefly highlighted. A preliminary screening is carried out on the basis of geological and field data from several fields of Tatarstan Republic, candidate fields are identified and a preliminary conclusion about LSW application in this region is made. The positive factors for the reservoirs under consideration, identified at the preliminary screening stage, include low formation temperature, high salinity of formation water with a significant content of divalent cations and the potential to shift the pH level from the current slightly acidic level towards increased alkalinity, and an increased content of polar oil components. In addition, the reservoirs of the Tulian and Bobrikovian horizons are characterized by the presence of clay particles, and the Devonian reservoir are characterized by a reduced oil viscosity coupled with an increased oil base number.
{"title":"Potential for improving the efficiency of terrigenous oil deposits waterflooding with the use of low salinity technology at fields of the Tatarstan Republic","authors":"Zalina R. Saptarova, Alexander A. Mamonov, S. Usmanov, A. Lutfullin, V. Sudakov, M. Shipaeva, A. Shakirov","doi":"10.18599/grs.2022.4.7","DOIUrl":"https://doi.org/10.18599/grs.2022.4.7","url":null,"abstract":"This article is devoted to the review of one of the currently relevant methods of enhanced oil recovery – low-salinity waterflooding (LSW) – on the example of terrigenous Tulian, Bobrikovian and Devonian reservoirs of the Tatarstan Republic fields.\u0000\u0000The first part of review contains information about the key processes underlying this method, such as swelling and migration of clay particles and wettability alteration, as well as the mechanisms that explain these processes, which include cation exchange, multicomponent ion exchange, electric double layer expansion, etc. Their understanding, in turn, contributes to the identification of the main factors, the presence or absence of which at the field allows us to give a preliminary assessment of LSW application. There are main factors: the presence of clay particles, a significant content of Ca2+ and Mg2+ ions, as well as multivalent ions in formation water, low formation permeability, reduced oil viscosity, an increased content of acidic and especially basic components in oil and, as a result, a hydrophobic type of initial rock wettability.\u0000\u0000Then, examples of using the method in other fields are given and the results of laboratory studies, including the measurement of the contact angle, core flooding experiments, are briefly highlighted.\u0000\u0000A preliminary screening is carried out on the basis of geological and field data from several fields of Tatarstan Republic, candidate fields are identified and a preliminary conclusion about LSW application in this region is made. The positive factors for the reservoirs under consideration, identified at the preliminary screening stage, include low formation temperature, high salinity of formation water with a significant content of divalent cations and the potential to shift the pH level from the current slightly acidic level towards increased alkalinity, and an increased content of polar oil components. In addition, the reservoirs of the Tulian and Bobrikovian horizons are characterized by the presence of clay particles, and the Devonian reservoir are characterized by a reduced oil viscosity coupled with an increased oil base number.","PeriodicalId":43752,"journal":{"name":"Georesursy","volume":"1 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67538205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The authors emphasize the need to take into account the uncertainty, conventionality and chances objectively inherent in the oil and gas industry when estimating oil and gas reserves and resources. It is noted that the current system in Russia for calculating and state accounting for reserves at least does not fully take them into account, nor does it meet the needs of business and financial structures, since the principles laid down in it do not correspond to generally accepted world standards. The authors come to the conclusion that the only reasonable choice for the institution of independent estimation (audit) of hydrocarbon reserves, which is beginning to form in Russia, is the use of the SPE-PRMS classification widely used in the world.
{"title":"What classification should be used in order to form the domestic system of independent expertise of hydrocarbon resources?","authors":"D.P. Zabrodin, E.A. Titkov","doi":"10.18599/grs.2022.4.1","DOIUrl":"https://doi.org/10.18599/grs.2022.4.1","url":null,"abstract":"The authors emphasize the need to take into account the uncertainty, conventionality and chances objectively inherent in the oil and gas industry when estimating oil and gas reserves and resources. It is noted that the current system in Russia for calculating and state accounting for reserves at least does not fully take them into account, nor does it meet the needs of business and financial structures, since the principles laid down in it do not correspond to generally accepted world standards.\u0000The authors come to the conclusion that the only reasonable choice for the institution of independent estimation (audit) of hydrocarbon reserves, which is beginning to form in Russia, is the use of the SPE-PRMS classification widely used in the world.","PeriodicalId":43752,"journal":{"name":"Georesursy","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44238005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study provides a new rock-typing approach for low-resistive and low-permeable clastic rocks. The approach includes integrated interpretation of routine core analysis data with microstructural characteristics, acquired from computed tomography (CT) and nuclear-magnetic resonance (NMR) data. The studied formation comprises siltstones in its bottom, which are replaced by sandstones in its top. Sandstones form the main part of the oil reservoir, whereas siltstones were originally considered as water-saturated. The reserves calculation was performed based on a single Archie equation for the whole formation. Despite on apparent water saturation and low permeability of the siltstones, incidental perforation showed considerable oil inflow from them as well. In order to delineate missed productive intervals within the low-resistive siltstones, we had to develop a new rock-typing approach, acknowledging rock multimineral composition, diversity of microstructures, a wide range of porosity, permeability, and residual water saturation values. Designed laboratory program included porosity, permeability, electrical resistivity measurements, capillary, NMR and CT tests. The experiments were performed on the same core samples that enabled reliable correlation between measured parameters. The joint interpretation of flow zone indicator, calculated as a function of porosity and residual water saturation, together with the results of petrophysical and microstructural measurements allowed reliable rock-typing of the clastic formation. It will serve as a petrophysical basis for identification of the missed productive intervals. The developed laboratory program and rock-typing algorithm can be implemented in other oilfields.
{"title":"The rock typing of complex clastic formation by means of computed tomography and nuclear magnetic resonance","authors":"A. Tchistiakov, E. Shvalyuk, Alexandr A. Kalugin","doi":"10.18599/grs.2022.4.9","DOIUrl":"https://doi.org/10.18599/grs.2022.4.9","url":null,"abstract":"This study provides a new rock-typing approach for low-resistive and low-permeable clastic rocks. The approach includes integrated interpretation of routine core analysis data with microstructural characteristics, acquired from computed tomography (CT) and nuclear-magnetic resonance (NMR) data.\u0000The studied formation comprises siltstones in its bottom, which are replaced by sandstones in its top. Sandstones form the main part of the oil reservoir, whereas siltstones were originally considered as water-saturated. The reserves calculation was performed based on a single Archie equation for the whole formation.\u0000Despite on apparent water saturation and low permeability of the siltstones, incidental perforation showed considerable oil inflow from them as well. In order to delineate missed productive intervals within the low-resistive siltstones, we had to develop a new rock-typing approach, acknowledging rock multimineral composition, diversity of microstructures, a wide range of porosity, permeability, and residual water saturation values.\u0000Designed laboratory program included porosity, permeability, electrical resistivity measurements, capillary, NMR and CT tests. The experiments were performed on the same core samples that enabled reliable correlation between measured parameters.\u0000The joint interpretation of flow zone indicator, calculated as a function of porosity and residual water saturation, together with the results of petrophysical and microstructural measurements allowed reliable rock-typing of the clastic formation. It will serve as a petrophysical basis for identification of the missed productive intervals.\u0000The developed laboratory program and rock-typing algorithm can be implemented in other oilfields.","PeriodicalId":43752,"journal":{"name":"Georesursy","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46987073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The geological study of reservoirs of heavy oil confined to the deposits of the Sheshma horizon, for further involvement of deposits in pilot production, is an expensive project in itself due to the high viscosity of oil from 200 to 200,000 MPa∙s and changes in the depth of the productive formation from 100 up to 500 m. It’s advisable to exclude all kinds of factors, including geological ones, leading to additional costs in the development of heavy oil deposits in an unstable economic situation. The purpose is determining of impact palaeovalley on the efficiency of wells using the example of heavy oil deposits. For the analysis authors have applied, materials the estimation of reserves, laboratory researches and macro descriptions of the core, the results of structural and geomorphological studies, and development parameters. It is viewed heavy oil deposits of the Sheshma horizon, complicated by palevalley, and geological structure. The porosity-permeability properties and characteristics of the bedding are given. The authors’re determined areas of palaeovalley the drilled wells, a macro description of the core and cuttings in the palaeovalley part are given. Zones of deconsolidation of the Upper Permian terrigenous deposits are identified by results of structural and geomorphological studies. A comparison of the map of predictive fracturing with the map of Pliocene formations characterizing the genesis of the palevalley is made. The authors’re comparisoned the operational capabilities of wells with the location of the wellhead in the palaeovalley zone and outside the palaeovalley. Recommendations for the design of horizontal wells complicated by palaeovalleys are determined.
{"title":"Features of geological structure heavy oil field complicated palaeovalley (P-N)","authors":"A. Bachkov, V. Bazarevskaya, D. Anoshin","doi":"10.18599/grs.2022.3.6","DOIUrl":"https://doi.org/10.18599/grs.2022.3.6","url":null,"abstract":"The geological study of reservoirs of heavy oil confined to the deposits of the Sheshma horizon, for further involvement of deposits in pilot production, is an expensive project in itself due to the high viscosity of oil from 200 to 200,000 MPa∙s and changes in the depth of the productive formation from 100 up to 500 m. It’s advisable to exclude all kinds of factors, including geological ones, leading to additional costs in the development of heavy oil deposits in an unstable economic situation.\u0000\u0000The purpose is determining of impact palaeovalley on the efficiency of wells using the example of heavy oil deposits. For the analysis authors have applied, materials the estimation of reserves, laboratory researches and macro descriptions of the core, the results of structural and geomorphological studies, and development parameters.\u0000\u0000It is viewed heavy oil deposits of the Sheshma horizon, complicated by palevalley, and geological structure. The porosity-permeability properties and characteristics of the bedding are given. The authors’re determined areas of palaeovalley the drilled wells, a macro description of the core and cuttings in the palaeovalley part are given. Zones of deconsolidation of the Upper Permian terrigenous deposits are identified by results of structural and geomorphological studies. A comparison of the map of predictive fracturing with the map of Pliocene formations characterizing the genesis of the palevalley is made. The authors’re comparisoned the operational capabilities of wells with the location of the wellhead in the palaeovalley zone and outside the palaeovalley. Recommendations for the design of horizontal wells complicated by palaeovalleys are determined.","PeriodicalId":43752,"journal":{"name":"Georesursy","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42078698","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Mudarisova, Y. Volkov, N. M. Khasanova, B. Uspensky
The use of the electron paramagnetic resonance (EPR) method for studying carbonate rocks is widespread. EPR makes it possible to reconstruct lithological and geochemical environments of ancient sedimentation, including redox conditions and paleo-radioactivity of sedimentation basins. The paper considers the heterogeneous structure of carbonate reservoir rocks of the Kazanian Stage of the Gorsky ultraviscous oil field by paramagnetic marks: manganese ions Mn2+, radical ions SO3–, SO2–, РO22-(РO20) in carbonate minerals and radical С600 in the remains of organic matter in the rock. The carbonate reservoirs of the Gorsky structure, tectonically confined to the eastern side of the Melekess Depression, are represented by two main lithotypes: dolomitic boundstones and dolomitic oolitic packstones, which have various post-sedimentary alterations. EPR data were obtained for 28 samples with a step of 0.5-1.5 m along the section. The EPR spectra are characterized by narrow lines that indicate the marine origin of carbonates. Based on the EPR spectra of the ions Mn2+ and its content in carbonate minerals, the lagoonal-marine genesis of the Gorsky structure rocks was revealed. The dominant dolomite mineralization of the section was established. The absence of dolomite radicals and low values of the degree of population of the magnesium and calcium positions of dolomites are due to the secondary nature of carbonates. The distribution of manganese ions, organic and inorganic radicals in the rock along the section is shown simultaneously with its reservoir properties and the conditions for the formation of two dolomite lithotypes.
{"title":"Carbonate reservoir rocks characterization of the Kazanian Stage of the Gorsky ultraviscous oil field by electron paramagnetic resonance method","authors":"R. Mudarisova, Y. Volkov, N. M. Khasanova, B. Uspensky","doi":"10.18599/grs.2022.3.8","DOIUrl":"https://doi.org/10.18599/grs.2022.3.8","url":null,"abstract":"The use of the electron paramagnetic resonance (EPR) method for studying carbonate rocks is widespread. EPR makes it possible to reconstruct lithological and geochemical environments of ancient sedimentation, including redox conditions and paleo-radioactivity of sedimentation basins. The paper considers the heterogeneous structure of carbonate reservoir rocks of the Kazanian Stage of the Gorsky ultraviscous oil field by paramagnetic marks: manganese ions Mn2+, radical ions SO3–, SO2–, РO22-(РO20) in carbonate minerals and radical С600 in the remains of organic matter in the rock. The carbonate reservoirs of the Gorsky structure, tectonically confined to the eastern side of the Melekess Depression, are represented by two main lithotypes: dolomitic boundstones and dolomitic oolitic packstones, which have various post-sedimentary alterations. EPR data were obtained for 28 samples with a step of 0.5-1.5 m along the section. The EPR spectra are characterized by narrow lines that indicate the marine origin of carbonates. Based on the EPR spectra of the ions Mn2+ and its content in carbonate minerals, the lagoonal-marine genesis of the Gorsky structure rocks was revealed. The dominant dolomite mineralization of the section was established. The absence of dolomite radicals and low values of the degree of population of the magnesium and calcium positions of dolomites are due to the secondary nature of carbonates. The distribution of manganese ions, organic and inorganic radicals in the rock along the section is shown simultaneously with its reservoir properties and the conditions for the formation of two dolomite lithotypes.","PeriodicalId":43752,"journal":{"name":"Georesursy","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47839258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}