Hydrogeological conditions of the Megionsky oil field

The aim of this study is to provide a comprehensive description of the underground hydrosphere of the Megionsky oil field. The field is located within the well-studied West Siberian megabasin. According to V. M. Matushevich's classification (1986), the stratigraphy of the Megionsky field is divided into three overlapping hydrogeological basins (Cenozoic, Mesozoic, and Paleozoic). The results of the analysis of the variation in water mineralization, formation pressures, and geothermal gradients with depth have justified the classification of the Megion oil field as a water-bearing system of the elision-type geodynamic origin. The aquifers and water-bearing complexes in the study area extensively utilized for drinking, domestic, and industrial water supply. Additionally, the Aptian-Albian-Cenomanian hydrogeological complex of the Mesozoic basin is also targeted for the disposal of excess associated water. These factors indicate a significant anthropogenic impact on hydrogeological systems. Understanding the hydrogeological features of the underground hydrosphere provides a foundation for designing measures to protect fresh and mineralized groundwater from contamination and depletion.