GEODYNAMICS

The aim of the work is to determine the possibility of using local seismological networks of nuclear power plants as elements of the seismological monitoring system of the territory of Ukraine. Estimation of local seismicity and specification of quantitative parameters of seismological influences is carried out on the basis of materials of seismological observations. Operational processing and analysis of seismic signals registered on the elements of local seismological networks of NPPs is carried out by the Main Center for Special Control of the State Space Agency of Ukraine (MCSC SSA of Ukraine). In the process of implementation of the “Seismic Hazard Assessment and Seismic Resistance Action Plan” of existing NPPs, seismic monitoring networks were deployed at Ukrainian NPPs. To date, the MCSC receives data from the local seismological networks of Rivne, Khmelnytsky and Zaporizhzhya NPPs in a continuous mode. The processing of geophysical information coming from the NPP to the FSC is carried out by the operational next shift of the center with the help of FSC hardware and software and provides reliable data on the parameters of seismic sources registered by stations, their location and energy characteristics. In total, in the period from 2017 to 2021, 36 local earthquakes were registered by NPP seismic networks in Ukraine. The epicenters of the vast majority of them are located within the Ivano-Frankivsk, Ternopil and Lviv regions. The experience of conducting instrumental observations at NPP seismic stations testifies to their high efficiency and possibility of use as full-fledged elements of the seismological monitoring system of the territory of Ukraine. According to the results of primary processing of seismic data of 2017-2021, a catalog of seismic events registered by NPP seismic stations was created. The system of interpretation of the obtained results was improved, which allowed to determine equally well local, regional and teleseismic events of different nature and energy level. The practical significance of the obtained results lies in their direct focus on solving a number of practical problems of processing and interpretation of seismological data. The use of NPP seismic stations as elements of the general system of seismological monitoring of Ukraine will increase the reliability of detection and localization of sources and the probability of correct identification of the nature of seismic phenomena, which in turn will improve the assessment of tectonic structures in Ukraine.

GEODYNAMICS

The aim of the research presented in this article is to analyze the properties and geological informative value of the anisotropic transformations of gravitational and magnetic fields, which use averaging procedures, including analysis of Andreev-Klushin's method. Anisotropic transformations of potential fields are designed to detect and track elongated anomalies or their chains, caused by deep linear dislocations in the geological section. The study of the anisotropic transformations properties is based on the analysis of their depth characteristics, as well as theoretical and practical experiments. The study applies the analysis method of fault tectonics reflection features in anisotropic anomalies of gravimagnetic fields, in particular, on the example of the South-East of the Ukrainian Carpathians. It is based on the search of morphological signs of manifestation of deep faults and other long structural-tectonic dislocations in gravitational and magnetic anisotropic anomalies. The method also suggests tracing these elements, relying on the comparison of morphology, intensity, size and direction of anisotropic anomalies with published regional tectonic and geological maps. Results. The paper presents definitions and algorithms of such anisotropic transformations as Andreev-Klushin's methods of anticlinal and terrace types, anisotropic averaging and anisotropic difference averaging. The research allowed us to perform study of the geological informative value of anisotropic transformations of potential fields on theoretical and practical examples. It is shown that in the morphology of anisotropic gravitational and magnetic anomalous fields in the south-east of the Ukrainian Carpathians long local anomalies are traced. They are caused by fault tectonics, in particular deep longitudinal and transverse faults, as well as linear complications into sedimentary cover. The analysis of anisotropic anomalous fields reveals a number of characteristic features of large tectonic zones reflecting regional behavior of the foundation surface and deep faults; on its basis fault tectonics schemes of the South-Eastern region of the Ukrainian Carpathians can be constructed. The study traced a significant extension of the foundation of the Eastern European platform from the Maidan's ledge and the Pokutsko-Bukovynian Carpathians under the Folded Carpathians. The definition of a number of anisotropic transformations is given and their properties are considered. The work substantiated geological informative value of the anisotropic transformations morphology of potential fields in the study of the Ukrainian Carpathians and adjacent depressions fault tectonics. The use of anisotropic transformations of potential fields will increase the reliability and detail of tracing deep faults, as well as other linear dislocations both in the foundation and in the sedimentary cover. The study of fault tectonics is an important factor in the successful solution of problems in the search and exploration of areas which are promising for oil and gas deposits.

GEODYNAMICS

The paper analyzes the vertical displacements of the GNSS sites of civil engineering structures caused by non-tidal atmospheric loading (NTAL). The object of the study is the Dnister Hydroelectric Power Plant №1 (HPP-1) and its GNSS monitoring network. The initial data are the RINEX-files of 14 GNSS stations of the Dnister HPP-1 and 8 permanent GNSS stations within a radius of 100 km, the NTAL model downloaded from the repository of German Research Centre for Geosciences GFZ for 2019-2021, and materials on the geological structure of the object. Methods include comparison and analysis of the altitude component of GNSS time series with model values of NTAL as well as interpretation of the geodynamic vertical displacements, taking into account the analysis of the geological structure. As a result, it was found that the sites of the GNSS network of the Dnister HPP-1 undergo less vertical displacements than the permanent GNSS stations within a radius of 100 km. This corresponds to the difference in thickness and density of the rocks under the GNSS sites and stations, so they undergo different elastic deformations by the same NTAL. In addition, the research detected different dynamics of vertical displacements of GNSS sites on the dam and on the river banks. It leads to cracks and deformations of concrete structures in the dam-bank contact zones. During the anomalous impact of NTAL, the altitude of even nearby sites can change if the geological structure beneath them is different. The work shows that for civil engineering structures it is necessary to apply special models to take into account NTAL deformations for high-precision engineering and geodetic measurements.

GEODYNAMICS

Purpose. To investigate the features of the algorithm implementation for finding the derivatives of the spatial distribution function of the planet's masses with the use of high-order Stokes constants and, on the basis of this, to find its analytical expression. According to the given methodology, to carry out calculations with the help of which to carry on the study of dynamic phenomena occurring inside an ellipsoidal planet. The proposed method involves the determination of the derivatives of the mass distribution function by the sum, the coefficients of which are obtained from the system of equations, which is incorrect. In order to solve it, an error-resistant method for calculating unknowns was used. The implementation of the construction is carried out in an iterative way, while for the initial approximation we take the three-dimensional function of the density of the Earth's masses, built according to Stokes constants up to the second order inclusive, by dynamic compression by the one-dimensional density distribution, and we determine the expansion coefficients of the derivatives of the function in the variables to the third order inclusive. They are followed by the corresponding density function, which is then taken as the initial one. The process is repeated until the specified order of approximation is reached. To obtain a stable result, we use the Cesaro summation method (method of means).. The calculations performed with the help of programs that implement the given algorithm, while the achieved high (ninth) order of obtaining the terms of the sum of calculations. The studies of the convergence of the sum of the series have been carried out, and on this basis, a conclusion has been made about the advisability of using the generalized finding of the sums based on the Cesaro method. The optimal number of contents of the sum terms has been chosen, provides convergence both for the mass distribution function and for its derivatives. Calculations of the deviations of mass distribution from the mean value ("inhomogeneities") for extreme points of the earth's geoid, which basically show the total compensation along the radius of the Earth, have been performed. For such three-dimensional distributions, calculations were performed and schematic maps were constructed according to the taken into account values of deviations of three-dimensional distributions of the mean ("inhomogeneities") at different depths reflecting the general structure of the Earth's internal structure. The presented vector diagrams of the horizontal components of the density gradient at characteristic depths (2891 km - core-mantle, 700 km - middle of the mantle, also the upper mantle - 200, 100 km) allow us to draw preliminary conclusions about the global movement of masses. At the same time, a closed loop is observed on the “core-mantle” edge, which is an analogy of a closed electric circuit. For shallower depths, differentiation of vector motions is already taking place, which gives hope for attracting these vector-grams to the study of dynamic motions inside the Earth. In fact, the vertical component (derivative with respect to the z variable) is directed towards the center of mass and confirms the main property of mass distributions - growth when approaching the center of mass. The method of stable solution of incorrect linear systems is applied, by means of which the vector-gram of the gradient of the mass distribution function is constructed. The nature of such schemes provides a tool for possible causes of mass redistribution in the middle of the planet and to identify possible factors of tectonic processes in the middle of the Earth, i.e indirectly confirms the gravitational convection of masses. The proposed technique can be used to create detailed models of density functions and its characteristics (derivatives) of the planet's interior, and the results of numerical experiments - to solve tectonics problems.

GEODYNAMICS

The article studies the system organization of inversion tectonic deformations of the Dnieper-Donetsk Basin which covered the territory of the Western Donetsk Graben. The research uses the kinematic and structural-paragenetic analysis of inversion structural transformation of the folded floors of the sedimentary cover of the Graben. The original model of tectonic inversion of the Dnieper-Donets Basin was completed from the previous models. The tectonic inversion of the Dnieper-Donets Paleorift rift-like structures began at the late Hercynian stage in the geodynamic environment of the territory of the Eastern European Platform general collision. Tectonophysical analysis shows that the inversion folding was formed by the mechanism of sedimentary horizons longitudinal bending in the environment of the interference of the intraplate submeridional collision compression and the regional strike-slip stress field. At the Mesozoic-Cenozoic stage, tectonic inversion continued in the field of right-hand strike-slip deformations with a variable compressive component. This caused the formation of folded covers of tectonic plates and scales in the uplift-thrust mode. They, Hercynian neo-autochthonous formations and further the weakly located syneclise autochthon of the South-east of the Basin. The pressure of the "tectonic stamp" geoblock of the Donetsk Foldbelt contributed to the formationof the Segment body of geomass Tectonic Wedging. It was diagnosed with a structural orocline of transverse extension of the sliding type. Large linear throw-folded zones were formed within geodynamic bands of injection and displacement of geomass along the front of the orocline. The tectonic compression fan, characteristic of geodynamic compression zones, was formed in the foreland of the orocline, on the ends of the main thrusts. They served as “tectonic rails”of the allochthon invasion within the rift-like structure. There are the transverse zones of tectonic sutures formed on the roots of the folding covers of the Hercynian neo-autochthon thrusting, which are located in the hinterland of the orocline in the Foldbelt Western slope. The study completed an original kinematic model of tectonic inversion of the transition zone between the Dnieper-Donets Basin and Donets Foldbelt. According to the model, the pressure of the “tectonic stamp” geoblock initiated the invasion of the Segment of Tectonic Wedging which consists of the intensively dislocated allochthonous geomass. The Segment destroyed the rift-like structure and formed the Western Donetsk Cover-Folded Region in the South-eastern part of the Basin. The system organization model of inversion complications of the rift-like structure in the territory of the Western Donetsk Graben will allow to improve the regional geological schemes of tectonic oil and gas zoning.

GEODYNAMICS

In order to study the deep structure of the southwestern Ukrainian Carpathians, where the Carpathian conductivity anomaly is located, in 2015 and 2020, modern synchronous magnetotelluric studies were carried out on the profiles of Mukachevo-Skole, Seredne-Borynya and Karpatsky at twenty-three points and the spatiotemporal distribution and the electric field on the Earth's surface, which can be used to assess the conductivity and geoelectrical structure of the region, was obtained. Processing of experimental data was performed using the software PRC_MTMV, which provides a common noise-canceling impedance estimation for synchronous magnetotellurical recordings. Curves of apparent electrical resistivity (amplitude values and phases of impedance) from 10 to 10000 s were obtained reliably. A joint analysis of the apparent resistivity and impedance phases and the formal interpretation of the deep magnetotellurical sounding curves using the Niblett transformation indicate the presence of the spatially inhomogeneous conductor both in the earth's crust and in the upper part of the upper mantle. The chain of local conductive sections in the earth's crust coincides with the axial part of the Carpathian conductivity anomaly. High conductivity of the upper mantle was recorded in the Ukrainian Carpathians from the Transcarpathian Depression to the Skiba cover. It is shown that it is not a homogeneous layer, there is a general deepening of the upper edge to the northeast from 40-60 km (Transcarpathian depression) to 90-100 km (Krosno cover). Sharp deepening along the Porkulets and Dukla covers is revealed. Information about the existence of a deep conductor and its parameters should be the basis for quantitative interpretation and construction of the 3D deep geoelectrical model.

GEODYNAMICS

The most dangerous exogenous geological processes (EGP) in terms of the amount of damage caused to economic objects include: landslides, karst, flooding, abrasion, mudslides, etc. The distribution and intensity of EGP are determined by the peculiarities of geological and geomorphological structure of the territory, its tectonic, neotectonic and seismic regime, as well as hydrological, climatic, hydrogeological paleo- and modern conditions. Solotvynsky salt mine is one of the oldest enterprises in Transcarpathia. The field has been exploited since the Roman Empire. In 1360, a settlement of salt miners, Solotvyno, was founded on the site of the mine, which later became a center of salt production and a royal monopoly. There are a total of nine mines in the field. In 1995-1996 and 2001, floods began flooding mines. In 2005, landslides and karst abysses intensified in Solotvyno, leading to damage to residential buildings, roads and infrastructure. There was a complete flooding of the mines of two mines. Currently, dangerous natural and man-made processes are observed on the territory of the salt mine and adjacent territories. This is mainly salt karst, both underground and surface, the collapse of areas in the location of mines, as well as landslides. Therefore, the purpose of the research is to conduct a geodynamic audit of SOLOTVYNSKY SALT MINE SE and the surrounding area with the possibility of identifying areas with subsidence or rise of the earth's surface, which are gradually slowing down, accelerating or developing at a constant rate. Output data. Radar interferometry data in the period from April 30, 2016 to June 25, 2018 were used for research and performance of geodynamic audit of SOLOTVYNSKY SALT MINE SE and the adjacent territory. Modern methods of interferometric processing of satellite radar data are used in the work: the method of "PS" – the method of constant scatterers, and the method SBAS – the method of small baselines. The method of geometric leveling was used to measure vertical displacements in some places on the earth's surface in order to verify interferometric data. Monitoring of the area of interest was carried out using modern technologies of satellite radar interferometry. According to the results of observations of landslides and individual objects by space (radar interferometry) and ground (geometric leveling) methods, a high correlation of data was recorded and the presence of zones of active subsidence in the mining area was confirmed.

GEODYNAMICS

The basic goal of this study (as the first step) is to collect the appropriate set of the fundamental astronomic-geodetics parameters for their further use to obtain the components of the density distributions for the terrestrial and outer planets of the Solar system (in the time interval of more than 10 years). The initial data were adopted from several steps of the general way of the exploration of the Solar system by iterations through different spacecraft. The mechanical and geometrical parameters of the planets allow finding the solution of the inverse gravitational problem (as the second stage) in the case of the continued Gaussian density distribution for the Moon, terrestrial planets (Mercury, Venus, Earth, Mars) and outer planets (Jupiter, Saturn, Uranus, Neptune). This law of Gaussian density distribution or normal density was chosen as a partial solution of the Adams-Williamson equation and the best approximation of the piecewise radial profile of the Earth, including the PREM model based on independent seismic velocities. Such conclusion already obtained for the Earth’s was used as hypothetic in view of the approximation problem for other planets of the Solar system where we believing to get the density from the inverse gravitational problem in the case of the Gaussian density distribution for other planets because seismic information, in that case, is almost absent. Therefore, if we can find a stable solution for the inverse gravitational problem and corresponding continue Gaussian density distribution approximated with good quality of planet’s density distribution we come in this way to a stable determination of the gravitational potential energy of the terrestrial and giant planets. Moreover to the planet’s normal low, the gravitational potential energy, Dirichlet’s integral, and other planets’ parameters were derived. It should be noted that this study is considered time-independent to avoid possible time changes in the gravitational fields of the planets.

GEODYNAMICS

Purpose. The aim of the research is mathematical analysis and forecasting of dispersive soils behaviour based on the study of inclinometric observations data in the area of the natural-technical system of the Dnister PSPP. Methodology. The research methodology is based on mathematical analysis and modelling of processes occurring in the mountain massif on which the Dnister PSPP is located, using the finite element method. Results. The paper presents an analysis of the results of geotechnical monitoring of the behaviour of dispersive soils, implemented on the basis of inclinometric measurements on the territory of the Dnister PSPP. Quantitative parameters of horizontal displacement distribution in inclinometric wells are established. They made it possible to detect negative dynamics in the geological horizons N1-2ap and N1p+v, which is apparently caused by technogenic load caused by the Dnister upper reservoir. The behaviour of dispersive soils under the influence of natural and technogenic loads has been modelled. Based on the simulation results, the change of the sign of deformations under the influence of additional load, which can be the filling of the Dnister upper reservoir, is confirmed. Obviously, the use of this method alone does not allow full detecting and tracking modern geological, seismic and geodynamic processes. A combination and detailed analysis of different monitoring methods (geophysical, geodetic, parametric, vibrometric, hydrogeological, temperature, visual-instrumental and others), as well as modelling the behaviour of the object under the influence of natural and technogenic factors is optimal. Such simulations could be used in the design of other objects of this type, so this is a promising area for further research. Originality. For the first time, a mathematical analysis and forecasting of the behaviour of dispersed soils in the area of the natural and technical system of the Dnister PSPP was conducted on the basis of studying the data of inclinometric observations. Practical significance. The proposed technique can be used in the design of other objects of this type, as modelling the behaviour of the object under the influence of natural and technogenic factors makes it possible to assess possible risks and prevent them.

GEODYNAMICS

Interest in research on the detection of earthquake (EQ) precursors is growing year by year. In this direction, the paper analysed the results of earlier studies, as well as positive results of some studies conducted in the last 5 years. In particular, during the study of EQs, ultra-low frequency (ULF) precursors attract special attention. The study compared the results of electromagnetic (EM) monitoring studies conducted in the ULF range in earlier years and the results of EM monitoring studies conducted in the last 5 years have been compared. The positive results of the researchers investigating the changes in the EM field before the EQ in the ULF range were reviewed. Thus, ULF anomalies from relatively weak (with 4<Mw<5) and shallow (with a depth of less than 50 km) EQs were repeatedly observed in 2017 in Indonesia. Before strong EQs, ULF promising EQ precursors were revealed. High ULF amplitude anomalies were recorded before the 2011 Tohoku megaEQ. Anomalous changes of the Earth's induction vector were identified in 6 observatories in Japan. Similar anomalies were also recorded in the ULF range (0.001-0.083 Hz) by the Teoloyucan (Mexico) and Tucson (the United States) geomagnetic observatories from August 1 to September 16, 2017, before the Chiapas EQ in Mexico with a magnitude 8.1. On the whole, the research discovered several dozen EM precursors of EQs with different amplitude, spectral and time parameters. The study was based on the analysis of numerous data for the periods 1976-2010 and 2007-2016 conducted by various researchers. In addition, an original approach is proposed. It consists in the study of geoelectric field changes (ULF precursors of EQs) as they are more sensitive. Processing and interpreting these changes can lead to precise detection of EQ precursors. Thus, this makes it possible to identify geodynamic active zones in which an EQ may occur.