Journals of Georgian Geophysical Society

The Impact of the Earthquake in Racha on the Enguri Arch Dam and the Adjacent Area

Jemal K. Kiria — 2024-12-23

As is well known, the Enguri Arch Dam, 271.5 meters high, was constructed on the Enguri River in the 1970s. It is built in a seismically active region with a complex geological structure.

The Enguri Dam’s foundation crosses a branch of the Ingirishi fault, on which geophysical monitoring (using a deformograph) is conducted. The fault’s edges move with the variation of the water level in the dam reservoir. Strong earthquakes can also cause displacement of the fault’s edges.

This was the basis for conducting parallel geological, geophysical, geodetic, and other types of monitoring during the design and construction of the dam, some of which continue to this day.

Confidence Interval of Parameters for Gaussian Statistical Structures Z-Criteria’s Application

Zurab S. Zerakidze — 2024-12-23

In this paper is proven 100% confidence interval of parameters for Gaussian statistical structures in Banach

space of measures.

The Radio Image of an Object with an Elongated, Face-Fragmented, Dielectrically Complex Structure was Studied Using the Method of Georadar Physical Modeling

David T. Odilavadze — 2024-12-23

Georadiolocation method has been widely used in many fields with geological content. Important results are obtained in the solution of many problematic issues of urban engineering, the solution of many tasks has become possible in archaeogeoradiolocation.

For archaeological work, it is important to fix and decipher the radio image of the object as a result of the mutual distance between the target objects and the georadar antenna. During archaeological work, the distance of the target object is unknown, which distorts or even makes it impossible to fix the radio image of the object. Important information may not be received.

A radio view of the object is allocated, which embeds the location of the object and exceeds its geometric dimensions spatially by approximately three times. At the same time, the lower part of the object is connected to the radio image in general with the so-called feature of antennas. With the content of the diagram of the direction of the electromagnetic field, that is, it clearly defines and separates the location of the object considered as a secondary radiation antenna.

Thus, it is possible to determine the physical model of the foundation and, therefore, the radio image of the field object based on the theory of the similarity of geolocation electromagnetic fields. The depth of the model object is clearly defined by the location of the last horizontal synch axis recorded on the radio face on the radargram, both during horizontal and vertical georadiolocation exposure.

Reaction of the Geomagnetic Field on the Earthquakes Preparation Process in Georgia

Tamar T. Jimsheladze — 2024-12-23

During the monitoring of earthquake precursors including extra information as the variations of electromagnetic fields analysis, it is possible to define earthquakes precursors is very actual and important problem. Connection between the variation of the geomagnetic field and seismic activities is an essential element of the fundamental problem of earthquake forecasting. In terms of geodynamic, Georgia is one of the most active regions. The macro structural factor here is represented by the contact with the Arabian and Eurasian tectonic plates, which in addition to the geological diversity of the area conditions the high seismicity of mentioned region. The article represents the observations of following seismic processes such as: geomagnetic field.

222Rn Concentration Levels in Soil Gas and Water in Kvemo Kartli Region, Georgia - 222Rn Mapping

Nino A. Kapanadze — 2024-12-23

Within the framework of the SRNSFG FN-19-22022 project “²²²Rn mapping and Radon risk assessment in Georgia”, the authors carried out fieldwork to quantify the ²²²Rn distribution in water and soil gas as well as to ascertain geological factors influencing the ²²²Rn concentration levels in some geographical areas of Georgia. On-site ²²²Rn concentration has been measured in soil gas (68 sampling points) and in various water sources (boreholes and springs, 75 water points, 66- springs, 9 boreholes) using AlphaGUARD PQ2000 PRO (Saphymo GmbH) Radon monitor. The ²²²Rn concentration ranged from 0.12 to 73 Bq/L in water and up to 36.9 Bq m^-3 in soil gas. All observation sites were marked by GPS position. The data underwent basic statistical analysis and were visualized using various plots. Subsequently, the field data were digitized and integrated into a GIS system, which highlighted the ²²²Rn distribution in water and soil gas on the territory of Kvemo Kartli.

On the Issue of Modelling the Dynamic Picture of the Spread of a Mudflow in the Shovi Gorge due to a Collapse on the Glacier Buba

Zurab A. Kereselidze — 2024-12-23

Glaciers have always been a potential hazard in the Caucasus region, where mountain canyons are quite densely populated. The processes associated with global climate change occurring everywhere have greatly exacerbated the problem of preventing the population from glacial disasters. For example, there is a sad experience associated with the collapse of the Kolka glacier, which caused a giant ice mudflow in 2002. A similar disaster should include the glacial mudflow from the Buba glacier on 9/3/2023, which resulted in a tragedy with numerous victims at the Shovi resort. Determining the possible place and time of development of such catastrophic events (earthquakes, volcanic eruptions, large-scale floods) has a very low degree of reliability and is problematic, despite the modern level of scientific methods of ground and space monitoring. In particular, there is an obvious need for long-term monitoring and comprehensive diagnostics of the current state of the Caucasus glaciers, taking into account each new experience. It should be noted that there is a paucity of information that allows us to judge the processes that have occurred on the Buba glacier over the past decades. Therefore, hardly anyone could imagine a large-scale virtual picture of the spread of a glacial mudflow along the gorges of the Bubistskali and Dzhandzhakhi rivers, adequate to what it turned out to be in reality. At the same time, in the case of a sufficiently complete database of observation results and its correct analysis, based on the principle of hydrodynamic similarity, there is a possibility of theoretical modeling of probable parameters of a flood or glacial mudflow in any mountain gorge. For example, in the case of the Caucasus region, one can use some of the results obtained by numerical modeling of the Dzhankuat and Kolka glaciers. In particular, these models are quite useful not only for determining probable causes, but also for retrospective analysis of the consequences of destruction on the Buba glacier. First of all. This concerns the process of propagation of hydrodynamic waves in a heterogeneous mudflow. For this purpose, records of seismic equipment are also important, which contain information on the frequency spectrum of acoustic waves generated by the process of destruction on the Buba glacier. Hydrodynamic waves of various types could have existed in the gorges of the Bubistskali and Chanchakhi rivers. In the characteristic range of the Froude similarity number, the most probable is the generation of running rolling waves, the height of which could reach several meters. The appearance of solitary waves (solitons), as well as the so-called gravity waves, was unlikely, but one cannot exclude the possibility of their generation in those places for which local conditions were suitable. In the lower, widest section of the Shovi gorge, in the zone of the so-called cottages, the movement of the mudflow was similar to the movement of the ice mudflow in the Genaldon River gorge after the collapse of the Kolka glacier in 2002. Despite the huge difference in the initial volumes of mudflows that came down from the Buba and Kolka glaciers, the deposit of viscoplastic mass in the last sections of its distribution turned out to be comparable taking into account the spatial scale and the amplitude of the waves in both cases decreased to heights of 1-3 meters.

Conical Model of Non-Uniform Rotation and Interaction of Elements of the Atmospheric Rotation Chain in a Linear Approximation

Zurab A. Kereselidze — 2024-12-23

The global atmosphere can be considered as an open thermodynamic system within which various disturbing factors act. For example, even in calm atmospheric conditions, orography can cause a violation of the stationary thermal balance between the Earth and the atmosphere. In general, the formation of vortex structures in any gaseous or liquid medium is stochastically determined. This means that the process of vortex formation is to a certain extent probabilistic. Therefore, in mathematical modeling of the field of atmospheric gyres, it is rational to exclude random factors by identifying specific contributing conditions. For example, a strong division of the earth's relief contributes to turbulence of air flows on a regional and local scale. In particular, the process of formation of low-intensity atmospheric vortices in mountain valleys can always be considered as a violation of local stability, the cause of which is the unevenness of the temperature field created at the boundary of different orography and landscapes. Also, the generation of vortices and the process of their dissipation in the atmosphere can always be considered as a violation of the stability of the environment on certain spatial scales, which is expressed in the violation of its thermodynamic parameters.

Coherent Analysis of Intense Geomagnetic Disturbances Using Dusheti Observatory Data and the DST Index

Luka K. Tsulukidze — 2024-12-23

Geomagnetic storms are intense disturbances in Earth’s magnetosphere that can disrupt technological systems and impact human health. This study investigates the dynamics of solar-terrestrial interactions using data from the Dusheti Observatory and global geomagnetic indices. We examined the relationships between the interplanetary magnetic field (IMF), sunspot numbers, and the H-component of the geomagnetic field during the period from 2023 to 2024, focusing on the unprecedented geomagnetic storm of May 11, 2024. Through wavelet coherence and cross-correlation analyses, we identified significant interactions between solar and geomagnetic activity, with coherence patterns emerging well before the storm onset. The analysis of six solar cycles (1964–2024) revealed correlation at lag of 5 days, highlighting the potential predictive utility of sunspot numbers. This study also validated the reliability of local geomagnetic data, emphasizing its importance for understanding the regional manifestations of global geomagnetic events in Georgia. The findings contribute to the development of improved predictive models for geomagnetic disturbances and underscore the need for localized studies to better mitigate the risks associated with space weather.

Some Results of the Joint Research of the M. Nodia Institute of Geophysics, TSU and Institute of Hydrometeorology, GTU from 2019 to 2023 and Prospects for their Further Development

Nodar D. Varamashvili — 2024-12-23

A brief information on joint research of the M. Nodia Institute of Geophysics, TSU and the Institute of Hydrometeorology, GTU, conducted in 2019–2023 and the prospects for their further development are presented.

International Scientific Conference “Complex Geophysical Monitoring in Georgia: History, Modern Problems, Promoting Sustainable Development of the Country”

Nodar D. Varamashvili — 2024-12-23

Information about the international scientific conference “Complex Geophysical Monitoring in Georgia: History, Modern Problems, Promoting Sustainable Development of the Country” Dedicated to 180 Anniversary of the Organization in Georgia of Regular Magneto-Meteorological Observations , which was held on October 17-19, 2024 at Ivane Javakhishvili Tbilisi State University is presented.