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This paper analyzes and reviews the rapid uplifts of the Earth's crust in the Caucasus that occurred over the last century. The uplifts were registered by precise repeated state leveling and reflected on officially published maps of vertical movements of the Earth's crust. This study summarizes information on the region's vertical movements over more than a century. The present study describes the technology for creating maps of recent vertical movements of the Earth's crust using precision leveling data. This paper summarizes cases of recording uplifts of the Earth's surface in other regions of the world in connection with seismic activity. The authors carried out intercomparison of vertical movements with tectonics, seismicity, and geophysical fields, which discovered their apparent mutual correspondence. This indicates the deep tectonic nature of the observed uplifts of the Earth's crust. Spatial and temporal agreement with the distribution of strong earthquakes showed a natural relationship. It has been shown that strong earthquakes are confined to the boundaries of zones of rapid uplift. They occur predominantly in areas of transition between uplifts and subsidence. The results obtained demonstrate the role of the study and observations of vertical movements of the Caucasus in assessing periods and areas of increased seismic hazard. [ABSTRACT FROM AUTHOR]

This paper analyzes and reviews the rapid uplifts of the Earth’s crust in the Caucasus that occurred over the last century. The uplifts were registered by precise repeated state leveling and reflected on officially published maps of vertical movements of the Earth’s crust. This study summarizes information on the region’s vertical movements over more than a century. The present study describes the technology for creating maps of recent vertical movements of the Earth’s crust using precision leveling data. This paper summarizes cases of recording uplifts of the Earth’s surface in other regions of the world in connection with seismic activity. The authors carried out intercomparison of vertical movements with tectonics, seismicity, and geophysical fields, which discovered their apparent mutual correspondence. This indicates the deep tectonic nature of the observed uplifts of the Earth’s crust. Spatial and temporal agreement with the distribution of strong earthquakes showed a natural relationship. It has been shown that strong earthquakes are confined to the boundaries of zones of rapid uplift. They occur predominantly in areas of transition between uplifts and subsidence. The results obtained demonstrate the role of the study and observations of vertical movements of the Caucasus in assessing periods and areas of increased seismic hazard.

The paper presents the results from upgrading the satellite geodetic network of the geodynamic test area of the Nizhne-Kansky massif using bedrock pin geodetic centers in 2021–2022. A brief review is given of the historical experience of using bedrock pin centers in developing satellite geodetic networks at geodynamic test sites, in particular, in areas where underground research laboratories are located. Based on this experience, the design and technology of installing rock geodetic centers were developed and implemented. The design of bedrock pin centers makes it possible to minimize the centering error and ensure immobility of GNSS equipment throughout the entire measurement session. The results of expanding the geodetic network in connection with the start of construction of an underground research laboratory in Krasnoyarsk krai are presented. The form of finite elements of the modernized geodetic network is analyzed. It is shown that construction of new GNSS stations had a positive effect on the network geometry. As a result, the network has increased the number of close-to-equilateral triangles (finite elements), which will have a positive effect on the accuracy in calculating the deformations of the Earth's surface when processing geodetic measurement results and when forecasting the long-term stability of the geological medium in the study area. [ABSTRACT FROM AUTHOR]

A geodynamic model of the northern part of the Nizhnekanskii massif is presented, developed in connection with the need to assess the safety of the insulating properties of geological formations during the disposal of high-level radioactive waste. The model is based on experimental data from GNSS observations of recent movements of the Earth's crust, obtained for the period from 2012 to 2021, the results of modeling the stress–strain state, and a systematic analysis of the relationship between deformation processes and tectonic block structures of the region. For an indirect assessment of the insulating properties of a rock mass based on the results of GNSS observations, it was proposed for the first time to use a parameter that characterizes the deficit of horizontal displacements of points of an observation network. [ABSTRACT FROM AUTHOR]

This article examines the study of modern crustal movements in the region of southwestern Bulgaria, a geologically and seismically active region with the presence of numerous fault structures. The main method of obtaining deformation information is by using GNSS measurements. The monitoring of geodynamic processes in the area has been going on for more than 25 years. GNSS data obtained from periodic campaign measurements between 1997 and 2022 are processed and analyzed to obtain the deformation accumulation result in southwestern Bulgaria. As a result of long-term measurements, more and more accurate and reliable results are obtained for the velocities of the points. A certain relationship has been established between the modern movements of the Earth's crust, seismic events and tectonic structures. This extensive movement of southern Bulgaria and northern Greece is also confirmed. The results can be used for a detailed geodynamic and geological study of the active fault structures in the area. [ABSTRACT FROM AUTHOR]

The aim of the work is the substantiate the development of a GNSS deformation monitoring network at the site of the underground research laboratory, for estimating the safety of underground isolation of radioactive waste in the Nizhne-Kansk massif. The article overviews the international experience of GNSS observations of recent crustal movements in the vicinities of underground research laboratories location (Switzerland, Finland, Sweden). The general information and main results of research works during 2010–2020 in the Nizhne-Kansk geodynamic test area are described. The article presents the prospects for extending the geodetic network in connection with the start of construction of the underground research laboratory. Based on the Delaunay triangulation we have analyzed the triangular finite elements of the existing and planned geodetic network. It is shown that the location of new points will significantly affect the geometry of the network. As a result, the number of near-equilateral triangles in the network will increase, which has a positive effect on increasing the accuracy in determining deformations of the Earth's surface when processing geodetic measurements. [ABSTRACT FROM AUTHOR]

The supplementary results are in agreement with previously obtained data that show southern motion of the stations with increasing velocities from north to south. They supplement the network in areas with missing data, but provide also new more accurate data at a local level. The velocities are from about 1.5 mm/y of the northernmost station to slightly over 3 mm in the southernmost station. They are significant for the interpretation of the present-day geodynamics and may be used as well as for the evaluation of the geological hazards. [ABSTRACT FROM AUTHOR]

Abstract: Today, one of the most topical questions in the recent geodynamics of eastern Asia is that concerning the existence of the Amurian Plate and its boundaries. An unambiguous answer is difficult to obtain because seismicity is relatively rare and weak and the plate boundaries are often geomorphologically unclear. One of the methods that can help is satellite geodesy. In the present study, the velocity field of recent horizontal crustal movements was obtained from five repeated GPS observations on the Amur–Zeya geodynamic test ground (Amur Region) in 2001–2007. On this basis, the parameters of the relative rotation of the Eurasian and Amurian plates were calculated. The coordinates of their rotation pole were found to be 122.285° E and 58.950° N, and the angular rotation velocity 0.095 deg/Myr. The resulting kinematic model describes the motion of the Eurasian and Amurian Plates as independent tectonic units. According to statistical analysis, this hypothesis is true at a confidence level of more than 99%. Also, calculations have shown that the eastern boundary of the Amurian Plate passes through a branch of the Tan-Lu fault system. The kinematic model for the Eurasian and Amurian Plates agrees well with data on the kinematics of active faults and the modern tectonic stress field at the plate boundary. [ABSTRACT FROM AUTHOR]

The calculation of recent crustal movements and the associated crustal deformation rely on a suitable interpolation of geodetic measurements with repetition cycles of years or decades and modern GPS permanent networks. A common interpolation methods is the least-square collocation (LSC). LSC requires some a priori assumptions about the characteristics of the velocity field, that is, stocasticity in Moritz's definition of LSC. We present a novel approach, called adaptative LSC (ALSC) to the interpolation of non-stochastic fields, which encompass the traditional LSC and the block model as special cases. This modified collocation method is based on the empirical estimation of a anisotropic and inhomogeneous covariance function of the interpolated field. The method has been tested on synthetic data that simulate geodetic measurements over a triple plate junction and with real data from precise levelling measurements over the Swiss Alps. In both cases, ALSC gave better and more stable results, compared to LSC and other interpolation methods, such as smoothed splines. [ABSTRACT FROM AUTHOR]