The initial results of observations of natural temperature variations with an accuracy of up to one thousandth of a degree in the deep underground adit of the Geophysical Observatory in the Northern ...Caucasus are presented. It is shown that tidal-driven changes in the stress–strain state of the geophysical medium lead not only to heat release due to shear displacements (effect of tidal friction), but also account for the observed “modulation” of the processes of the release of volatile fluids from the underground rocks (so-called “sponge effect”). Thus, the diurnal and semidiurnal harmonics observed in microvariations of the underground temperature may be associated with the convective component of heat and mass transfer, which is largely determined by the corresponding changes in the regime of regular fluid migration due to the periodic influence of the combined solar–lunar tide effects on the geophysical medium in the deep underground tunnel.
The spectral and dynamic parameters of the sources of regional seismic events for the territory of the Northwest Caucasus has been studied based on the data from the stations of the Geophysical ...Survey, Russian Academy of Sciences, and from the Crimean seismic network. This is the first study for this region using such a large dataset and comparing the values of the moment and local magnitudes. The relationships for the moment and local magnitudes are established for earthquakes of small and medium magnitudes in the study area and the linear dependence
M
w
=
M
L
+ 0.16 is recommended for use. A relationship connecting values of energy classes and local magnitudes is also obtained, to help in further improvement of the procedures for processing of seismological monitoring data from the stations of the Caucasus region and the preparation of unified regional catalogs.
The results of long-term experimental observations of tidal deformations of the Earth’s crust are reported. These studies have been conducted with the use of the unique laser interferometer of the ...Sternberg State Astronomical Institute (GAISh), Moscow State University, installed in the deep underground tunnel of the Baksan Neutrino Observatory. A fifteen-year series of continuous in-situ observations of the lithospheric deformations and the corresponding theoretical calculated values of the tide with the basic lunar wave M
2
being distinguishing have been analyzed. The features of the tidal response have been studied for a given volume of the layered geophysical medium on the basis of the data obtained. Changes in the amplitude and phase parameters of the medium were analyzed taking into consideration the patterns of the seismic process. The possibilities of using the parameters of the tidal response of the geophysical medium as possible indicators of the formation and development of focal structures of regional seismic events were considered.
Observations reflecting the structure and conditions of the seismogravitational process in the lithosphere were analyzed using the data on the catastrophic tsunamigenic earthquake of Maule (Chile) ...Sobisevich et al., 2019. Seismogravitational processes were first identified by a group of Soviet scientists from the city of Leningrad (now St. Petersburg) under the leadership of Professor E.M. Linkov Linkov et al., 1982, 1990. The study of these processes continues at the North Caucasus Geophysical Observatory of IPE RAS, which was established in 2004. Experiments are carried out using unique quartz tiltmeters designed by D.G. Gridnev, which ensure the stable registration of long–period seismogravitational processes on the scale of the Earth Sobisevich, 2013; Sobisevich et al., 2017.
The paper presents seismological, forecasting, and seismotectonic data on the strong March 25, 2020 earthquake in the Northern Kurils. The collected materials on an unusual deep lithospheric ...earthquake in the border area of the Northern Kurils and Southern Kamchatka made it possible to understand the structure of the source of this event, as well as to determine the features of the seismic process in it. The variability of release of the scalar seismic moment (
M
0
) made it possible to trace the seismic history over the past 110 years in the preparation zone of the March 25 earthquake. The dynamics of development of the aftershock process in terms of the release of
M
0
was also studied.
This paper presents the results of areal seismic studies in the deep structure of the Dzhau Tepe mud volcano, which is the largest of its kind on the Kerch Peninsula. It is the first time that data ...has been obtained concerning nearly vertical fluid-conducting structures beneath the volcano that supply material onto the ground during more active periods. A new approach is proposed for interpretation of measured relative amplitudes of microseismic noise based on numerical simulation of plane-stratified media. The results derived in this study are compared with previous geological and geophysical data on the area.
In this paper, the results of lidar monitoring of magmatic aerosol variation are presented. The lidar was installed in a hot dead-end tunnel at the end of the auxiliary adit of the Baksan Neutrino ...Observatory (BNO) of the Institute for Nuclear Research, Russian Academy of Sciences, which is located above the small magma chamber of the Elbrus Volcanic Center. A sharp (within ~30 min) threefold increase in the aerosol concentration in the hot tunnel was detected (October 28, 2019, 22:30 UTC). The analysis involved data on volumetric radon activity, air temperature, and humidity. A synchronous increase in temperature, humidity, and aerosol concentration in the tunnel, as well as their correlation with the deformation of the Earth’s crust by tidal waves, which is monitored at the BNO with a laser strainmeter, was revealed. However, the threefold jump did not appear in these signals. The totality of data confirms the existence of a hot magma chamber at the base of Mount Andyrchi that was previously discovered by a small-aperture seismometer group. The assumption that the release of gases from the magma chamber could provide a jump in the concentration of aerosols without disturbing other parameters is discussed.
The paper presents the results of both theoretical and experimental studies carried out in the framework of the integrated problem on improving national systems for high-precision instrumental ...observations using the IPE RAS Geophysical Observatory in the Northern Caucasus. The geophysical observatory is located in the vicinity of the Mt. Elbrus in a deep underground tunnel of the Baksan Neutrino Observatory, supervised by INR RAS. Along with general information about the underground laboratory, the significant performance characteristics of the main instrument—a two-axial tiltmeter—are presented, as well as the data acquisition, processing, and storage system. The influence of natural and technogenic disturbances on the results of interpreting both tidal harmonics and other long-period variations are estimated via the developed technique to minimize the impact of a separate class of disturbances; an express estimate of the amplitude of the observed tide is performed.
Problems concerning the occurrence and development of dangerous endogenous processes in southern regions of Russia are considered. Based on analysis of primary data from the seismological network, ...the Q-factor of the layered geophysical medium and the attenuation of the elastic wave energy are estimated. The newly obtained data argue for the hypothesis about a possible domain of manifestation of fluid-magmatic processes in the Elbrus volcanic area.
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