Engineering-geological zoning of the central area of the Upper Kama Potassium–Magnesium Deposit in view of salt karst propagation

Abstract

With a view to geological and environmental safety of the central area of the Upper Kama Potassium–Magnesium Salt Deposit, the engineering-geological zoning is performed to identify karst-sensitive land. The zoning is based on two most fundamental factors: hydrogeology and neotectonics. Evaluation of the first factor consisted in determining the thicknesses of suprasalt deposits and the size of fresh groundwater zone by analyzing the data of exploration wells and other geological and hydrogeological materials, as well as calculating the thickness of the separating stratum corresponding to the interval of deposits from the top of the salt stratum to the lower boundary of the zone of fresh groundwater. The analysis of the second, neotectonic, factor was associated with the identification of increased fracturing zones in rock mass based on the grouping of faults and lineaments obtained from the interpretation of cosmic and aerial photographs, as well as from the construction and analysis of digital elevation models during field route observations. The comparison of two factors made it possible to zone the territory of research into areas with different degrees of protection of the salt stratum from the potential development of karst: high, medium and low. Within the areas with a low degree of protection, the further detailed studies of the hydrodynamic regime of groundwater and their interaction with the host rocks are necessary. The described method of engineering-geological zoning can find application to provide natural and technological safety in underground mining areas. The results obtained can be used in design of systems of special-purpose geodetic and hydrogeological monitoring.The research was carried out under the state contract, Topic No. AAAA-A19-119021190076-9.