GEOLOGICAL PHENOMENON OF MUD VOLCANOSIS ON APRIL 26–27, 2023 IN THE VILLAGE OF ROZVADIV, STRYI DISTRICT, LVIV REGION

Abstract

An analysis of a single manifestation of mud volcanism was conducted on the night of April 26-27, 2023 in the coastal part of the village of Rozvadiv, Stryi district, Lviv region, to the Dniester River. All manifestations were documented by local residents in the form of publicly available photo and video materials. The localization of the studied area near gas-bearing areas and fault zones gave us reason to call the observed phenomena a manifestation of mud (sedimentary) volcanism, which is one of the most interesting geological phenomena, and which is of great importance for understanding the geotectonic position of this territory, the search for hydrocarbon deposits, seismicity, potential geological hazards and environmental consequences associated with greenhouse gas emissions. A characteristic feature of the described geological phenomenon is the passage here of a clear geotectonic boundary between the Bilche-Volytskyi zone of the Precarpathian trough and the East European platform, tectonic disturbance, increased gasification of the soil massif, where the Rozvadiv geological phenomenon was observed - the first manifestation of mud volcanism in the Lviv region, primarily due to the above-mentioned features of the geotectonic position and geological structure. Geological manifestations of mud volcanism in the village of Rozvadiv on the night of April 26 to 27, 2023 were: 1) sudden gas emissions in the form of griffins on the left bank of the Dniester River at a distance of several tens to several hundred meters from the riverbed; 2) airlift effects in the first Quaternary aquifer from the surface, which manifested itself in the "boiling" of water in wells and raising their level above the daytime surface, up to spontaneous discharge; gushing of water (pulp) saturated with gas and suspended clay particles to a height of 5-7 meters. 4) one-time formation of multiple explosive-erosive calderas of various sizes from 1 by 1 m and 2-3 m deep to 2 by 5 m and 3-4 m deep with their flooding with water; 5) residual degassing of the soil massif, which continued to degas for some time with the release of gas with a noticeable smell of hy drogen sulfide. The described manifestation of mud volcanism has already caused negative consequences and can potentially be repeated. The probable natural and man-made factors of the activation of mud volcanism are substantiated. To clarify the exact causes, detailed studies of this geological phenomenon are necessary in order to ensure environmental safety.