Pub Date : 2022-02-07DOI: 10.24028/gzh.v43i6.251566
S. Shcherbina, P. G. Pigulevskyi, I. Gurova, T. Amashukeli, L. Shumlianska, O. A. Kalinichenko, I. Kalitova, D. Malytsky, V. G. Nikulin, S. T. Verbytsky
The article concerns results of studying two significant seismic events — an explosion (23.09.2020 09:00) and an earthquake (30.09.2020 20:00), which occurred in the area of the city of Kryvyi Rih. There were developed algorithms to process records by the Kryvyi Rih seismic station. There was done a comprehensive interpretation of the seismologic and geological-geophysical data. The seismic events’ coordinates were determined, the quality of seismological data processing was evaluated based on the expert method, the level of trustworthiness of the resulting parameters was estimated. The nature of the eathquake’s origin was analyzed based on the shape and the records’. The structure of the mechanism of the earthquake center shows that this was a natural seismic event of the induced type. The article also provides results of geotectonics study of the region of its origin and shows the connection of the geological structures with the epicenter’s parameters. The parameters of the stress-strain state of the crust in the Kryvyi Rih iron-ore basin are calculated, and the parameters of the epicenter of the induced earthquake (2020.09.30 20:00:40.836, UTC) are established. The experimentally calculated depth of the epicenter of local earthquake coincides with the hypothetical depth of 15 km at the lower edge of faults according to the model of the distribution of the depths of the earthquake hypocenters on the Eastern European platform. The proposed methods and algorithms open new opportunities for modern geophysical research in the long-term seismic hazard assessment of Kryvyi Rih. Meanwhile, for a more precise determination of the place, time and nature of local seismic events in the area it is necessary to develop, here and on adjacent territories, a network of seismic stations capable of recording events of comparable and lesser magnitude.
{"title":"A study of the properties of the tectonic structure of the Kryvyi Rih city based on statistical analysis of seismicity","authors":"S. Shcherbina, P. G. Pigulevskyi, I. Gurova, T. Amashukeli, L. Shumlianska, O. A. Kalinichenko, I. Kalitova, D. Malytsky, V. G. Nikulin, S. T. Verbytsky","doi":"10.24028/gzh.v43i6.251566","DOIUrl":"https://doi.org/10.24028/gzh.v43i6.251566","url":null,"abstract":"The article concerns results of studying two significant seismic events — an explosion (23.09.2020 09:00) and an earthquake (30.09.2020 20:00), which occurred in the area of the city of Kryvyi Rih. There were developed algorithms to process records by the Kryvyi Rih seismic station. There was done a comprehensive interpretation of the seismologic and geological-geophysical data. The seismic events’ coordinates were determined, the quality of seismological data processing was evaluated based on the expert method, the level of trustworthiness of the resulting parameters was estimated. The nature of the eathquake’s origin was analyzed based on the shape and the records’. The structure of the mechanism of the earthquake center shows that this was a natural seismic event of the induced type. The article also provides results of geotectonics study of the region of its origin and shows the connection of the geological structures with the epicenter’s parameters. The parameters of the stress-strain state of the crust in the Kryvyi Rih iron-ore basin are calculated, and the parameters of the epicenter of the induced earthquake (2020.09.30 20:00:40.836, UTC) are established. The experimentally calculated depth of the epicenter of local earthquake coincides with the hypothetical depth of 15 km at the lower edge of faults according to the model of the distribution of the depths of the earthquake hypocenters on the Eastern European platform. The proposed methods and algorithms open new opportunities for modern geophysical research in the long-term seismic hazard assessment of Kryvyi Rih. Meanwhile, for a more precise determination of the place, time and nature of local seismic events in the area it is necessary to develop, here and on adjacent territories, a network of seismic stations capable of recording events of comparable and lesser magnitude.","PeriodicalId":54141,"journal":{"name":"Geofizicheskiy Zhurnal-Geophysical Journal","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2022-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47758429","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}
Pub Date : 2022-02-07DOI: 10.24028/gzh.v43i6.251562
O. Rusakov, V. Starostenko, A. I. Yakimchik
The article presents an analysis of the statistical data from the Web of Science platform on the publication activity of the researchers of the Institute of Geophysics from 1974 to 2020. 1382 articles are indexed in the Web of Science Core Collection. They have been published in 107 journals of 18 countries in 5 languages. The distribution of publications over the years clearly shows two peaks. The first one (1981—1990) is due to the fact that «Geophysical Journal International» since 1981 for 10 years has been completely translated into English and distributed abroad. During this time, half of the journal’s articles have been indexed in the Web of Science. The second peak is a consequence of the journal’s inclusion in 2015 the Web of Science. The self-citation index is 17 %, which corresponds to the world indicator for the section «Geology». Over the past twenty years, when the SCI Journal began publishing the freely available Internet Impact Factor Database of journals that are part of the Web of Science, 181 articles have been posted in 73 journals whose impact factors range from 0,046 to 7,000 with an average value of 1,785. The Hirsch index is defined for 71 researchers. Its average value is 5, which is higher for 29,6 % of researchers. The practice was discussed for using the Hirsch index in Ukraine and Russia in sollution of employee issues and allocating grants for scientific research. The Hirsch index is shown to have a wider scope of its application in our neighbors and it plays a more influential role.
{"title":"Analyzing the statistics for publication activity of the researchers of the S.I. Subbotin Institute of Geophysics, NAS of Ukraine for 1974—2020 in the scientometric database Webof Science","authors":"O. Rusakov, V. Starostenko, A. I. Yakimchik","doi":"10.24028/gzh.v43i6.251562","DOIUrl":"https://doi.org/10.24028/gzh.v43i6.251562","url":null,"abstract":"The article presents an analysis of the statistical data from the Web of Science platform on the publication activity of the researchers of the Institute of Geophysics from 1974 to 2020. 1382 articles are indexed in the Web of Science Core Collection. They have been published in 107 journals of 18 countries in 5 languages. The distribution of publications over the years clearly shows two peaks. The first one (1981—1990) is due to the fact that «Geophysical Journal International» since 1981 for 10 years has been completely translated into English and distributed abroad. During this time, half of the journal’s articles have been indexed in the Web of Science. The second peak is a consequence of the journal’s inclusion in 2015 the Web of Science. The self-citation index is 17 %, which corresponds to the world indicator for the section «Geology». Over the past twenty years, when the SCI Journal began publishing the freely available Internet Impact Factor Database of journals that are part of the Web of Science, 181 articles have been posted in 73 journals whose impact factors range from 0,046 to 7,000 with an average value of 1,785. The Hirsch index is defined for 71 researchers. Its average value is 5, which is higher for 29,6 % of researchers. The practice was discussed for using the Hirsch index in Ukraine and Russia in sollution of employee issues and allocating grants for scientific research. The Hirsch index is shown to have a wider scope of its application in our neighbors and it plays a more influential role.","PeriodicalId":54141,"journal":{"name":"Geofizicheskiy Zhurnal-Geophysical Journal","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2022-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47933534","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}
Pub Date : 2022-02-07DOI: 10.24028/gzh.v43i6.251567
A. Chernov, A. Ivko, O. Bulakh
In this paper results of Antarctic ice caps investigations with GPR are represented. Local glaciological investigations of small glaciers on islands at the western coast of the AP are rare. Ice thickness is an important parameter for ice mass balance calculation. Investigation of the layering and in-situ sampling help to reveal information about past climate conditions and to understand glacio-geological history of the region. However, modern database Global Terrestrial Network for Glaciers contains neither the information about the thickness nor about interior structure of the ice caps discussed in this paper. The research is aimed at investigating the thickness and interior structure of the ice caps on Antarctic islands Plйneau, Petermann, Booth, Berthelot and Dannebrog. This territory was described only on the level of pioneering research in 19—20th centuries. The aim of the research is to obtain data about the general structure of the ice caps and ice thickness. Ground penetrating radar (GPR) VIY 3-300 (300 MHz) was applied to the surveying. Processed GPR profiles show up to 14 layers (Plйneau) inside the ice caps. There are interior crevasses, zones of moisture concentration and voids. Maps of the ice thickness were built for each island. The ice thickness on Dannebrog, Booth and part of Plйneau islands is more than 27 m, so it is recommended to use less frequency of the antennae than 300 MHz for a deeper and more detailed research of these ice caps. There are crevasses inside the ice near the surface, so for further investigations it is better to use special equipment to prevent any emergency situations (ropes, crampons, ice-hammerd, etc.). Landing sites on the islands with better access to the territories are mentioned in this paper.
{"title":"Reconnaissance GPR survey of the ice caps on islands of Wilhelm Archipelago and on Berthelot island (West Antarctica)","authors":"A. Chernov, A. Ivko, O. Bulakh","doi":"10.24028/gzh.v43i6.251567","DOIUrl":"https://doi.org/10.24028/gzh.v43i6.251567","url":null,"abstract":"In this paper results of Antarctic ice caps investigations with GPR are represented. Local glaciological investigations of small glaciers on islands at the western coast of the AP are rare. Ice thickness is an important parameter for ice mass balance calculation. Investigation of the layering and in-situ sampling help to reveal information about past climate conditions and to understand glacio-geological history of the region. However, modern database Global Terrestrial Network for Glaciers contains neither the information about the thickness nor about interior structure of the ice caps discussed in this paper. The research is aimed at investigating the thickness and interior structure of the ice caps on Antarctic islands Plйneau, Petermann, Booth, Berthelot and Dannebrog. This territory was described only on the level of pioneering research in 19—20th centuries. The aim of the research is to obtain data about the general structure of the ice caps and ice thickness. Ground penetrating radar (GPR) VIY 3-300 (300 MHz) was applied to the surveying. Processed GPR profiles show up to 14 layers (Plйneau) inside the ice caps. There are interior crevasses, zones of moisture concentration and voids. Maps of the ice thickness were built for each island. The ice thickness on Dannebrog, Booth and part of Plйneau islands is more than 27 m, so it is recommended to use less frequency of the antennae than 300 MHz for a deeper and more detailed research of these ice caps. There are crevasses inside the ice near the surface, so for further investigations it is better to use special equipment to prevent any emergency situations (ropes, crampons, ice-hammerd, etc.). Landing sites on the islands with better access to the territories are mentioned in this paper.","PeriodicalId":54141,"journal":{"name":"Geofizicheskiy Zhurnal-Geophysical Journal","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2022-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44300219","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}
Pub Date : 2022-02-07DOI: 10.24028/gzh.v43i6.251552
V. Entin, M. Orlyuk, O. I. Belous, O. Gintov, V. Malakhov, V. Bakhmutov, I. A. Kachan, M. Bakarzhieva, I. Makarenko, O. Savchenko, T.M. Samoilenko, A. Marchenko, V. Drukarenko, I. Poliachenko, S. Mychak, A. Romenets, O. Braiko
The article presents the results of the newest research performed by the State Enterprise «Ukrainian Geological Company» and the Institute of Geophysics of the National Academy of Sciences of Ukraine in 2021 to find out the morphology and elements of occurrence of an redeposit within the limits of the Gorishne-Plavninsk-Lavrikovsk area of the Krivoy Rog-Kremenchug iron-ore strip. In the process of geological and geophysical studies, a large body of new geological and geophysical data was obtained regarding the deep structural and morphological features of the construction of the Gorishne-Plavninsk structure (GPS), associated with the Krivoy-Rog deep fracture zone. Materials of reinterpretation of previously per formed ground-based magnetometric and gravimetric surveys, detailed high-altitude aeromagnetic studies and the study of the density and magnetic properties of the structure rocks, including the anisotropy of magnetic susceptibility using new equipment and techniques, gravimagnetic modeling with the construction of three-dimensional volume model of the structure lead to the conclusion that this structure is a typical drag fold with a pronounced reversal of its southern part by the right-hands hear. Its primary formation occurred as a faulted band of sedimentary-volcanogenic and extrusive formations of subvertical bedding and spreading to a depth of at least 1.5—2 km. A complete morphological and kinematic analogue of the GPS is the previously studied Likhmanovsk structure, located in the southern most part of the Krivoy Rog-Kremenchug strip. Many iron-ore structures of the Middle Bug area are close to it in structure and kinematics, the primary subvertical faulting and doubtful sedimentary genesis were mentioned earlier. All these data require a new approach to the study of iron-ore and some other deposits of the Ukrainian Shield associated with fault tectonics, as well as to the genesis problems and stratigraphy of rocks of the Early Precambrian.
{"title":"Depth structure of the Gorishne-Plavninsk structure and general principles of geological and geophysical study of the Krivoy Rog-Kremenchug iron-ore strip","authors":"V. Entin, M. Orlyuk, O. I. Belous, O. Gintov, V. Malakhov, V. Bakhmutov, I. A. Kachan, M. Bakarzhieva, I. Makarenko, O. Savchenko, T.M. Samoilenko, A. Marchenko, V. Drukarenko, I. Poliachenko, S. Mychak, A. Romenets, O. Braiko","doi":"10.24028/gzh.v43i6.251552","DOIUrl":"https://doi.org/10.24028/gzh.v43i6.251552","url":null,"abstract":"The article presents the results of the newest research performed by the State Enterprise «Ukrainian Geological Company» and the Institute of Geophysics of the National Academy of Sciences of Ukraine in 2021 to find out the morphology and elements of occurrence of an redeposit within the limits of the Gorishne-Plavninsk-Lavrikovsk area of the Krivoy Rog-Kremenchug iron-ore strip. In the process of geological and geophysical studies, a large body of new geological and geophysical data was obtained regarding the deep structural and morphological features of the construction of the Gorishne-Plavninsk structure (GPS), associated with the Krivoy-Rog deep fracture zone. \u0000Materials of reinterpretation of previously per formed ground-based magnetometric and gravimetric surveys, detailed high-altitude aeromagnetic studies and the study of the density and magnetic properties of the structure rocks, including the anisotropy of magnetic susceptibility using new equipment and techniques, gravimagnetic modeling with the construction of three-dimensional volume model of the structure lead to the conclusion that this structure is a typical drag fold with a pronounced reversal of its southern part by the right-hands hear. Its primary formation occurred as a faulted band of sedimentary-volcanogenic and extrusive formations of subvertical bedding and spreading to a depth of at least 1.5—2 km. \u0000A complete morphological and kinematic analogue of the GPS is the previously studied Likhmanovsk structure, located in the southern most part of the Krivoy Rog-Kremenchug strip. Many iron-ore structures of the Middle Bug area are close to it in structure and kinematics, the primary subvertical faulting and doubtful sedimentary genesis were mentioned earlier. All these data require a new approach to the study of iron-ore and some other deposits of the Ukrainian Shield associated with fault tectonics, as well as to the genesis problems and stratigraphy of rocks of the Early Precambrian.","PeriodicalId":54141,"journal":{"name":"Geofizicheskiy Zhurnal-Geophysical Journal","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2022-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42451345","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}
Pub Date : 2022-02-07DOI: 10.24028/gzh.v43i6.251560
V. Isaev, D. S. Krutenko, G. Lobova, E. Osipova, V. Starostenko
This paper maps the heat flow density from the pre-Jurassic basement within a large territory of oil accumulation (circa 120 thousand sq. km) in the South-East of Western Siberia. Values of heat flow, calculated for 201 deep wells, comprise a dataset for developing the map with contour lines for every 2 mW/m2. These values were calculated by solving the inverse problem of Geothermy — one-dimensional initial-boundary value problem for equation of thermal conductivity in a solid with the moving upper boundary. The accepted mathematical statement is sufficiently accurate for modeling near horizontal bedded sedimentary section: existence of heat flow convectional component is taken into account via calculation of an effective heat flow value. The map shows different types of anomalous features of heat flow density distribution. Previously it was stated for Western Siberian Plate that values of deep heat flow within positive tectonic structures of sedimentary cover are 5—20 % higher than within negative tectonic structures. As it is, combined analysis of deep heat flow density distribution and location of tectonic structures (Kaimysov arch, Parabelmegaarch, especially Alexandrov arch and Pudino mega swell) shows tendency among positive tectonic structures for increasing deep heat flow value. However, it is not always so. For example, there is the utterly different correlation for the Srednevasyugan mega swell. This structure is characterized with lower heat flow. The location of the Nizhnevartovsk arch is almost untraceable in the deep heat flow density distribution. Concerning oil-and-gas potential ... (?) A large positive anomaly has formed in the zone around the Traigorodsko-Kondakov field in the north. Two positive anomalies are in the central part of the map: around the Snezhnoe field and close by the Lomovoe, the Ozernoe and the Katylgin fields. Such fields as the Rybalnoe, the Pindzhin and the Mirnoe surround a positive anomaly in the southeastern part of the map. This paper contains a catalogue of discrete values (by wells) and a map of heat flow, which may be used as a «framework» in basin modeling. Upcoming research concerning origin of heat flow density anomalies — graded assessment of possible influence of tectonics, material composition and oil-and-gas potential of basement rocks has theoretical and practical significance.
{"title":"Mapping of Western Siberian heat flow (southeast)","authors":"V. Isaev, D. S. Krutenko, G. Lobova, E. Osipova, V. Starostenko","doi":"10.24028/gzh.v43i6.251560","DOIUrl":"https://doi.org/10.24028/gzh.v43i6.251560","url":null,"abstract":"This paper maps the heat flow density from the pre-Jurassic basement within a large territory of oil accumulation (circa 120 thousand sq. km) in the South-East of Western Siberia. Values of heat flow, calculated for 201 deep wells, comprise a dataset for developing the map with contour lines for every 2 mW/m2. These values were calculated by solving the inverse problem of Geothermy — one-dimensional initial-boundary value problem for equation of thermal conductivity in a solid with the moving upper boundary. The accepted mathematical statement is sufficiently accurate for modeling near horizontal bedded sedimentary section: existence of heat flow convectional component is taken into account via calculation of an effective heat flow value. The map shows different types of anomalous features of heat flow density distribution. Previously it was stated for Western Siberian Plate that values of deep heat flow within positive tectonic structures of sedimentary cover are 5—20 % higher than within negative tectonic structures. As it is, combined analysis of deep heat flow density distribution and location of tectonic structures (Kaimysov arch, Parabelmegaarch, especially Alexandrov arch and Pudino mega swell) shows tendency among positive tectonic structures for increasing deep heat flow value. However, it is not always so. For example, there is the utterly different correlation for the Srednevasyugan mega swell. This structure is characterized with lower heat flow. The location of the Nizhnevartovsk arch is almost untraceable in the deep heat flow density distribution. Concerning oil-and-gas potential ... (?) A large positive anomaly has formed in the zone around the Traigorodsko-Kondakov field in the north. Two positive anomalies are in the central part of the map: around the Snezhnoe field and close by the Lomovoe, the Ozernoe and the Katylgin fields. Such fields as the Rybalnoe, the Pindzhin and the Mirnoe surround a positive anomaly in the southeastern part of the map. \u0000This paper contains a catalogue of discrete values (by wells) and a map of heat flow, which may be used as a «framework» in basin modeling. Upcoming research concerning origin of heat flow density anomalies — graded assessment of possible influence of tectonics, material composition and oil-and-gas potential of basement rocks has theoretical and practical significance.","PeriodicalId":54141,"journal":{"name":"Geofizicheskiy Zhurnal-Geophysical Journal","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2022-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45310022","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}
Pub Date : 2022-02-07DOI: 10.24028/gzh.v43i6.251557
M. Kozlenko, Y. Kozlenko
The study of the calculation features of two-dimensional density models with different ratios of the curves of the gravity anomalies and the calculated gravitating effect is carried out on the example of the South Ukrainian monocline within the Black Sea. Studies have shown that a decrease in the magnitude of the residual anomaly (Δgr) taking into account the accuracy of its determination can result in both a refinement of the structure of the Earth’s crust and its almost complete restructuring. In this case, the nature of changes in the structure of the Earth’s crust depends on the type of residual anomaly that needs to be reduced. The smoothing of curves Δgr of the same sign only leads to a more precise section, while those of different signs forming the Helmert anomalies lead to a significant restructuring of the model due to the need to mutually correlate the influence of closely spaced contrasting changes in gravitating masses (compaction and decompaction), which can give a qualitative leap in the study of the structure of the lithosphere. In particular, a decrease in the residual anomaly to ±2.0 mGal when modeling the structure of the Earth’s crust within the Biostromnaya zone made it possible to identify apromising area for the search for hydrocarbons. Therefore, at the stage of prospecting, it is necessary to recalculate in greater detail the sections of the profile in the zones of lateral changes in the field, if in the density simulations the curves of Δgr have the form of Helmert anomalies.
{"title":"Influence of the residual anomaly features on the detail of 2D density models","authors":"M. Kozlenko, Y. Kozlenko","doi":"10.24028/gzh.v43i6.251557","DOIUrl":"https://doi.org/10.24028/gzh.v43i6.251557","url":null,"abstract":"The study of the calculation features of two-dimensional density models with different ratios of the curves of the gravity anomalies and the calculated gravitating effect is carried out on the example of the South Ukrainian monocline within the Black Sea. Studies have shown that a decrease in the magnitude of the residual anomaly (Δgr) taking into account the accuracy of its determination can result in both a refinement of the structure of the Earth’s crust and its almost complete restructuring. In this case, the nature of changes in the structure of the Earth’s crust depends on the type of residual anomaly that needs to be reduced. The smoothing of curves Δgr of the same sign only leads to a more precise section, while those of different signs forming the Helmert anomalies lead to a significant restructuring of the model due to the need to mutually correlate the influence of closely spaced contrasting changes in gravitating masses (compaction and decompaction), which can give a qualitative leap in the study of the structure of the lithosphere. In particular, a decrease in the residual anomaly to ±2.0 mGal when modeling the structure of the Earth’s crust within the Biostromnaya zone made it possible to identify apromising area for the search for hydrocarbons. Therefore, at the stage of prospecting, it is necessary to recalculate in greater detail the sections of the profile in the zones of lateral changes in the field, if in the density simulations the curves of Δgr have the form of Helmert anomalies.","PeriodicalId":54141,"journal":{"name":"Geofizicheskiy Zhurnal-Geophysical Journal","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2022-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41679960","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}
Pub Date : 2022-02-07DOI: 10.24028/gzh.v43i6.251549
I. Logvinov, G. Boyadzhiev, B. Srebrov, L. Rakhlin, G. Logvinova, S. Timoshin
The task of the work was geoelectrical studies using variations of the magnetotelluric (MT) field of the Kozloduy nuclear power plant (KNPP) region and the integration of its results with other geological and geophysical knowledge. This paper presents the determined interpretation parameters of the MT field. The KNPP is located on the right bank of the Danube River in close proximity to the river. This fact, together with the location of electrified railways determined the unique network of locations of observation points for MT field variations. Based on the analysis of Earthquake Catalogs of Bulgaria and international seismicity databases, a map of the seismicity of nuclear power plant areas was built. Over the past 50 years, about 750 earthquakes (mainly south of KNPP) have been recorded at a distance of 40—80 km from the KNPP. Two magnetotelluric stations GEOMAG-02 were used at measurement sites, but equipment for recording electrical channels was available only for one station (due to the lack of another set of non-polarizable electrodes). The MT field variations were observed at 21 points, which are located on the territory with sides approximately 30—35 km from east to west and 40—50 km from north to south. For all observation points on the profile, only the parameters of the vertical magnetic transfer function (VMPF) were determined, in the form of the real (Cu) and imaginary (Cv) parts of the induction vector. The steadily induction vector was defined for periods from 10—20 to 4900—10 800 s. For most points it was possible to estimate the values Cu, Cv with an error of 0.02—0.04 and AzCu, AzCv 3—5°. The analysis showed the presence of anomalous behavior of Cu, Cv in different intervals of periods at some points. In the shortest (about 20 s) and longest periods (600 to 1000 s), the Cu directions completely coincide and indicate the presence of anomalous conductivity of the quasi-longitudinal strike to the west of the study area. This behavior of the Cu vector is in good agreement with power isohypsum strike of the Cenozoic deposits. At intermediate periods of 50—200 s, the behavior of Cu is more complex. Approaching the zone of high seismicity, the direction of the Cu differs from the previous ones by almost 90°. On the Geoelectrical sections, obtained as a result of 1D inversions of MTS curves at 4 points located in the southern part of the region, anomalous layers are identified (ρ about 10 ohm · m, the depth of the center of the object is 15—20 km). It can be assumed that well-conducting objects in the Earth’s crust of the region, apparently, prevent the propagation of seismic waves from nearby earthquakes to the north towards the KNPP.
{"title":"Geoelectric studies of the Kozloduy nuclear power plant region, Bulgaria","authors":"I. Logvinov, G. Boyadzhiev, B. Srebrov, L. Rakhlin, G. Logvinova, S. Timoshin","doi":"10.24028/gzh.v43i6.251549","DOIUrl":"https://doi.org/10.24028/gzh.v43i6.251549","url":null,"abstract":"The task of the work was geoelectrical studies using variations of the magnetotelluric (MT) field of the Kozloduy nuclear power plant (KNPP) region and the integration of its results with other geological and geophysical knowledge. This paper presents the determined interpretation parameters of the MT field. The KNPP is located on the right bank of the Danube River in close proximity to the river. This fact, together with the location of electrified railways determined the unique network of locations of observation points for MT field variations. Based on the analysis of Earthquake Catalogs of Bulgaria and international seismicity databases, a map of the seismicity of nuclear power plant areas was built. Over the past 50 years, about 750 earthquakes (mainly south of KNPP) have been recorded at a distance of 40—80 km from the KNPP. Two magnetotelluric stations GEOMAG-02 were used at measurement sites, but equipment for recording electrical channels was available only for one station (due to the lack of another set of non-polarizable electrodes). The MT field variations were observed at 21 points, which are located on the territory with sides approximately 30—35 km from east to west and 40—50 km from north to south. For all observation points on the profile, only the parameters of the vertical magnetic transfer function (VMPF) were determined, in the form of the real (Cu) and imaginary (Cv) parts of the induction vector. The steadily induction vector was defined for periods from 10—20 to 4900—10 800 s. For most points it was possible to estimate the values Cu, Cv with an error of 0.02—0.04 and AzCu, AzCv 3—5°. The analysis showed the presence of anomalous behavior of Cu, Cv in different intervals of periods at some points. In the shortest (about 20 s) and longest periods (600 to 1000 s), the Cu directions completely coincide and indicate the presence of anomalous conductivity of the quasi-longitudinal strike to the west of the study area. This behavior of the Cu vector is in good agreement with power isohypsum strike of the Cenozoic deposits. At intermediate periods of 50—200 s, the behavior of Cu is more complex. Approaching the zone of high seismicity, the direction of the Cu differs from the previous ones by almost 90°. On the Geoelectrical sections, obtained as a result of 1D inversions of MTS curves at 4 points located in the southern part of the region, anomalous layers are identified (ρ about 10 ohm · m, the depth of the center of the object is 15—20 km). It can be assumed that well-conducting objects in the Earth’s crust of the region, apparently, prevent the propagation of seismic waves from nearby earthquakes to the north towards the KNPP.","PeriodicalId":54141,"journal":{"name":"Geofizicheskiy Zhurnal-Geophysical Journal","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2022-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43249124","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}
Pub Date : 2021-11-24DOI: 10.24028/gzh.v43i5.244077
O. Kendzera, Y. Semenova
The research presented in the work aims to assess the seismic response of three different taxonometric sites, identified by the method of engineering and geological analogies within the territory of Kyiv, to seismic loads with different spectral content and peak amplitude from 0.01 g to 0.06 g. Assessment of the influence of local soil conditions on the intensity of earthquakes is an important task of earthquake-resistant design and construction. The soil layer at the base of the study site acts as a filter on seismic vibrations. It amplifies or attenuates the amplitude of the seismic wave propagating from the bedrock to the free surface. The paper considers the mechanisms of the possible amplification of seismic motions by various soil complexes and methods for calculating the seismic response to seismic loads of various intensities. As an analytical tool for analyzing the response of the taxonometric areas to seismic vibrations (seismic response), an equivalent linear analysis was used, which is comprehensively studied and widely used in engineering seismology. For the selected sites, models of soil strata were built, and graphs of changes with depth of peak shear strain and peak ground acceleration (PGA) were calculated, as well as predicted (expected with a given probability of non-exceeding) amplitude Fourier spectra of seismic motions in the upper layer and the response spectra of single oscillators with 5 % attenuation to seismic effects with a maximum amplitude from 0.01 g to 0.06 g. A comparative analysis of the change in the value of these parameters in individual sections of Kyiv is presented. It is shown that to assess the potential hazard from seismic ground motions during earthquakes, it is necessary to use the maximum number of design parameters that characterize the seismic hazard of specific areas and which are used to determine the seismic resistance of buildings and structures. The most complete seismic hazard for calculating the seismic stability of objects is set by the full vector of seismic motions deployed in time: calculated accelerograms, seismograms and velocigrams. The presented calculation results are planned to be used in solving methodological and practical problems of earthquake protection, which can be realized in different parts of the territory of Kyiv.
{"title":"Seismic response of various sites of the territory of Kyiv to seismic loads","authors":"O. Kendzera, Y. Semenova","doi":"10.24028/gzh.v43i5.244077","DOIUrl":"https://doi.org/10.24028/gzh.v43i5.244077","url":null,"abstract":"The research presented in the work aims to assess the seismic response of three different taxonometric sites, identified by the method of engineering and geological analogies within the territory of Kyiv, to seismic loads with different spectral content and peak amplitude from 0.01 g to 0.06 g. Assessment of the influence of local soil conditions on the intensity of earthquakes is an important task of earthquake-resistant design and construction. The soil layer at the base of the study site acts as a filter on seismic vibrations. It amplifies or attenuates the amplitude of the seismic wave propagating from the bedrock to the free surface. The paper considers the mechanisms of the possible amplification of seismic motions by various soil complexes and methods for calculating the seismic response to seismic loads of various intensities. As an analytical tool for analyzing the response of the taxonometric areas to seismic vibrations (seismic response), an equivalent linear analysis was used, which is comprehensively studied and widely used in engineering seismology. For the selected sites, models of soil strata were built, and graphs of changes with depth of peak shear strain and peak ground acceleration (PGA) were calculated, as well as predicted (expected with a given probability of non-exceeding) amplitude Fourier spectra of seismic motions in the upper layer and the response spectra of single oscillators with 5 % attenuation to seismic effects with a maximum amplitude from 0.01 g to 0.06 g. A comparative analysis of the change in the value of these parameters in individual sections of Kyiv is presented. It is shown that to assess the potential hazard from seismic ground motions during earthquakes, it is necessary to use the maximum number of design parameters that characterize the seismic hazard of specific areas and which are used to determine the seismic resistance of buildings and structures. The most complete seismic hazard for calculating the seismic stability of objects is set by the full vector of seismic motions deployed in time: calculated accelerograms, seismograms and velocigrams. The presented calculation results are planned to be used in solving methodological and practical problems of earthquake protection, which can be realized in different parts of the territory of Kyiv.","PeriodicalId":54141,"journal":{"name":"Geofizicheskiy Zhurnal-Geophysical Journal","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2021-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49306703","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}
Pub Date : 2021-11-24DOI: 10.24028/gzh.v43i5.244080
T. Tsvetkova, I. Bugaenko, L. N. Zaets
This work is devoted to studying the velocity structure of the mantle of the border area of the East European and West European platforms in the crust separated by the Teiserre-Tornquist zone. The mantle under the territory of Poland and Western Ukraine is being investigated. The work uses a three-dimensional P-velocity model of the mantle, constructed using the Taylor approximation method developed by V. S. Geyko. The method’s advantages are independent of the initial approximation (reference model) and the best approximation of nonlinearity. In this area, the exploration depth is 2500 km south of 50 °NL and 1700 km north of 50 °NL. A detailed analysis of horizontal sections of a 3D P-velocity model of the mantle up to a depth of 850 km with a step of 50 km has been carried out. The change in the spatial distribution of the zero seismic velocity boundary is analyzed throughout the depths. This boundary separates the high-velocity upper mantle of the East European Platform and the low-velocity upper mantle of the West European Platform. At the depths of the transition zone of the upper mantle, this boundary separates the low-velocity upper mantle of the East European platform and the high-velocity upper mantle of the West European platform (in this geosphere, a velocity inversion has occurred with respect to the upper mantle). In latitudinal sections, two inclined layers are distinguished. One of them is associated with the upper mantle under the DDV and reaches the mantle under the Carpathians, where it begins to plunge into the high-velocity transition zone of the upper mantle. The second layer is associated with the mantle under the northwestern end of the Baltic syneclise, which extends to the mantle under the Presudet monocline, where it also plunges into the high-velocity transition zone of the upper mantle. In longitudinal sections, inclined layers are distinguished, extending from the mantle under the South Scandinavian megablock of the Baltic Shield to the mantle under the Bohemian massif and the Carpathians, where they plunge into the high-velocity transition zone of the upper mantle. In the study area, three super-deep fluids were identified, characterized by increased stratification of the medium (alternation of higher and lower velocities). The first includes the well-known oil and gas fields of the Central European oil and gas basin (Pomorie and Presudet monocline (Poland)). The second is associated with oil and gas fields of the North Ciscarpathian oil and gas basin (southeastern Poland) and the Carpathian oil and gas basin (Western Ukraine). The extracted super-deep fluid in the mantle of the Baltic Sea corresponds to both the Gdansk Gulf of the Baltic Sea and the Kaliningrad fields (southeast of the Baltic Sea).
{"title":"Speed structure of the mantle of the border of the Eastern European and West European platforms","authors":"T. Tsvetkova, I. Bugaenko, L. N. Zaets","doi":"10.24028/gzh.v43i5.244080","DOIUrl":"https://doi.org/10.24028/gzh.v43i5.244080","url":null,"abstract":"This work is devoted to studying the velocity structure of the mantle of the border area of the East European and West European platforms in the crust separated by the Teiserre-Tornquist zone. The mantle under the territory of Poland and Western Ukraine is being investigated. The work uses a three-dimensional P-velocity model of the mantle, constructed using the Taylor approximation method developed by V. S. Geyko. The method’s advantages are independent of the initial approximation (reference model) and the best approximation of nonlinearity. In this area, the exploration depth is 2500 km south of 50 °NL and 1700 km north of 50 °NL. A detailed analysis of horizontal sections of a 3D P-velocity model of the mantle up to a depth of 850 km with a step of 50 km has been carried out. The change in the spatial distribution of the zero seismic velocity boundary is analyzed throughout the depths. This boundary separates the high-velocity upper mantle of the East European Platform and the low-velocity upper mantle of the West European Platform. At the depths of the transition zone of the upper mantle, this boundary separates the low-velocity upper mantle of the East European platform and the high-velocity upper mantle of the West European platform (in this geosphere, a velocity inversion has occurred with respect to the upper mantle).\u0000In latitudinal sections, two inclined layers are distinguished. One of them is associated with the upper mantle under the DDV and reaches the mantle under the Carpathians, where it begins to plunge into the high-velocity transition zone of the upper mantle. The second layer is associated with the mantle under the northwestern end of the Baltic syneclise, which extends to the mantle under the Presudet monocline, where it also plunges into the high-velocity transition zone of the upper mantle. In longitudinal sections, inclined layers are distinguished, extending from the mantle under the South Scandinavian megablock of the Baltic Shield to the mantle under the Bohemian massif and the Carpathians, where they plunge into the high-velocity transition zone of the upper mantle.\u0000In the study area, three super-deep fluids were identified, characterized by increased stratification of the medium (alternation of higher and lower velocities). The first includes the well-known oil and gas fields of the Central European oil and gas basin (Pomorie and Presudet monocline (Poland)). The second is associated with oil and gas fields of the North Ciscarpathian oil and gas basin (southeastern Poland) and the Carpathian oil and gas basin (Western Ukraine). The extracted super-deep fluid in the mantle of the Baltic Sea corresponds to both the Gdansk Gulf of the Baltic Sea and the Kaliningrad fields (southeast of the Baltic Sea).","PeriodicalId":54141,"journal":{"name":"Geofizicheskiy Zhurnal-Geophysical Journal","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2021-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47089834","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}
Pub Date : 2021-11-24DOI: 10.24028/gzh.v43i5.244065
V. Bakhmutov, D. Hlavatskyi, Y. Veklych, V. Shpyra, V. Yakukhno
We present the results of a palaeomagnetic study of the Early—Middle Pleistocene deposits exposed on the left bank of the River Danube at Dolynske, southern Ukraine. A thick succession of water-lain facies is succeeded by stratigraphically complete loess-palaeosol sequence; these constitute a unique palaeoclimate archive in the southern margin of the East European loess province. The Matuyama—Brunhes boundary (MBB) has been detected at the bottom of the Lower Shyrokyne (S7S3) subunit and not in the Martonosha (S6) unit as previously thought. New data align with previous results from the Roksolany and Vyazivok sections, where the MBB was determined at the same stratigraphical level in the S7S3 soil. In contrast to terrestrial Pleistocene records in China and сentral Europe, where the MBB was regularly determined in a loess layer (representing a cold period), the MBB in the Ukrainian subaerial succession is located in the soil unit (representing a warm period). Furthermore, eight, and not seven, glacial-interglacial cycles are recorded in the Brunhes chron. This may indicate the stratigraphic completeness of the loess-soil succession of Ukraine, which can be compared with the reference global marine and terrestrial palaeoclimatic archives. Further palaeomagnetic studies of loess-palaeosol sequences of other regions of Ukraine will allow revision and correlation of still inconsistent stratigraphic and magnetostratigraphic schemes of the Pleistocene deposits.
{"title":"The Matuyama—Brunhes boundary in the loess-palaeosol sequence of Dolynske, southern Ukraine","authors":"V. Bakhmutov, D. Hlavatskyi, Y. Veklych, V. Shpyra, V. Yakukhno","doi":"10.24028/gzh.v43i5.244065","DOIUrl":"https://doi.org/10.24028/gzh.v43i5.244065","url":null,"abstract":"We present the results of a palaeomagnetic study of the Early—Middle Pleistocene deposits exposed on the left bank of the River Danube at Dolynske, southern Ukraine. A thick succession of water-lain facies is succeeded by stratigraphically complete loess-palaeosol sequence; these constitute a unique palaeoclimate archive in the southern margin of the East European loess province. The Matuyama—Brunhes boundary (MBB) has been detected at the bottom of the Lower Shyrokyne (S7S3) subunit and not in the Martonosha (S6) unit as previously thought. New data align with previous results from the Roksolany and Vyazivok sections, where the MBB was determined at the same stratigraphical level in the S7S3 soil. In contrast to terrestrial Pleistocene records in China and сentral Europe, where the MBB was regularly determined in a loess layer (representing a cold period), the MBB in the Ukrainian subaerial succession is located in the soil unit (representing a warm period). Furthermore, eight, and not seven, glacial-interglacial cycles are recorded in the Brunhes chron. This may indicate the stratigraphic completeness of the loess-soil succession of Ukraine, which can be compared with the reference global marine and terrestrial palaeoclimatic archives. Further palaeomagnetic studies of loess-palaeosol sequences of other regions of Ukraine will allow revision and correlation of still inconsistent stratigraphic and magnetostratigraphic schemes of the Pleistocene deposits.","PeriodicalId":54141,"journal":{"name":"Geofizicheskiy Zhurnal-Geophysical Journal","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2021-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48913629","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}
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