Keywords: Kryvbas, groundwater, Ingulets River, hydrofiltration, geophysical observations, mine waters, tectonic zones

The study is devoted to investigating the impact of large-scale water discharge from the Karachunivske Reservoir on hydrogeodynamic processes within the geological environment of the Southern Kryvbas using geophysical methods. The main objective of the research was to assess the influence of mining activities in the open pit on the Inhulets River and adjacent geological structures. The research methodology is based on monitoring field observations carried out using geophysical techniques, including electrical prospecting, particularly the method of natural field (self-potential), as well as gravimetric surveys. The obtained results demonstrate that a sharp increase in the water level in the Inhulets River leads to intensive infiltration of excessive surface waters into the sedimentary cover and tectonically disturbed zones. This process significantly alters the hydrogeodynamic state of rocks and contributes to the activation of landslide processes within the study area. The analysis of geophysical data revealed a clear dependence of the natural field potential and its gradient on the processes of water saturation of the geological medium. In addition, the key role of tectonic faults in controlling the pathways of water filtration and redistribution within the subsurface has been established. It has been determined that in areas with open fault systems, water penetrates deeper into the geological section, whereas in zones with closed fault systems, it spreads laterally within interlayer spaces. These processes are reflected in the spatial distribution of geophysical parameters and confirm the sensitivity of the natural field method to changes in hydrogeological conditions. The scientific novelty of the study lies in confirming the effectiveness of the natural field method for investigating the mechanisms of rapid water saturation of geological formations and identifying pathways of surface water migration into underground horizons. Furthermore, the results substantiate the applicability of this method for environmental monitoring of flooded and landslide-prone areas, as well as for the optimization of observation networks and early detection of hazardous geological processes in mining regions.

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