UNDERGROUND EXPLORATION OF POTASSIUM SALT DEPOSITS OF THE PRECARPATHIAN TREADMILL OF THE WESTERN REGION OF UKRAINE

Abstract

Within the Precarpathian depression of the western region of Ukraine, more than 20 deposits of potash salts have been previously explored, which are characterized by a tectonically disturbed geological structure, including manifestations of salt tectonics, a specific and variegated mineral composition of ores, and complex mining, geological, and hydrogeological conditions. The Stebnytske and Kalush-Holynske deposits have been exploited here for more than 100 years, the development of which revealed a number of specific characteristics that must be taken into account before the start of mining, namely at the stages of geological exploration and g eological and economic assessment. The peculiarities of the geological structure, mineral composition, morphology of ore bodies formed under conditions of strong influence of geotectonic processes on the occurrence of deposits, water solubility of ores and host rocks, risks of activation of salt karst and other dangerous geological processes, significantly limit traditional approaches to the assessment of reserves of potassium salt deposits within the Precarpathian depression, especially their reliability in comparison with other – insoluble in water types of mineral raw materials. In this regard, for their geological and economic assessment, additional exploration and operational exploration, the most effective and reliable approaches are proposed, taking into account the minimization of risks of disruption of hydrogeological conditions, initiation of water inflows, activation of salt karst and other dangerous geological processes. The essence of the proposed approach for hydrogeologically safe additional exploration and operational exploration of potash deposits is the passage of exploration shafts of mines, horizontal cross-cuts, drifts, underground drilling and testing of ore bodies within the allocated blocks, establishing the exact thickness of deposits, mineral and chemical composition. In the event of a negative result of the geological and economic assessment, which will require significant costs, primarily related to the costs of mining and tunneling and underground drilling, the potential subsoil user can use the underground space of the geological environment as a resource for speleotherapy.