Identification of Natural and Technogenic Decompacted Zones in the Worked-Out Massif Based on High-Precision Gravimetric Observations

Abstract

The paper presents the results of gravimetric studies at the potassium salt deposit in order to obtain information on the development of negative engineering-geological processes in the rock mass caused by subsoil development. A methodology was developed for high-precision monitoring gravimetric observations, which makes it possible to determine the change in the field over time. A physico-geological model of gravimetric monitoring, representing a homogeneous geological medium with an isolated area in which rock density changes have occurred, has been created. For the purposes of gravimetric monitoring, a method for processing and interpreting dynamic gravity anomalies based on the synthesis of qualitative and quantitative methods for extracting geological information from gravimetric data has been adapted. The result of the interpretation is the area of distribution, the probable interval of depths of rock decompaction, as well as the magnitude of the change in rock density, which characterizes the intensity of the process of decompaction. Examples are given of testing the developed technology for dividing decompressed zones into natural and man-made zones at the Verkhnekamskoye potash deposit in order to improve the safety of its operation. It is shown that the results of monitoring gravimetric observations can predict areas of dangerous geological processes and control subsidence of the earth's surface.