Estimation Of Geodynamic Activity And Its Impact On Mining-Geological Conditions And Flooding Of Potassium Mines
Kopylov, Igor Sergeevich
Perm State University, Russian Federation
Geodynamic active zones (or simply geo-active zones) are areas of the earth's crust that are active at the present stage of neotectonic development, characterized by increased fracturing, permeability, manifestations of discontinuous tectonics, seismicity and other processes. They are a powerful factor in the formation and changes in the ecological, hydrogeological and mining and geological conditions of the territories of the development of mineral resources and often lead to accidents in mines.
The problem of forecasting of geodynamic dangerous zones at early stage of potash deposits development is very important for providing safe mining operation. In result of insufficient geological studies and/or improper mine planning more than 80 potash mines have been flooded over the past 150 years in the world.
The author and others have developed special techniques for assessing geodynamic (neotectonic) activity of territories - morphoneotectonic, lineament-geodynamic and landscape-geodynamic analyzes based on remote sensing, which allow to reliably establish geoactive zones of various levels - from regional (with areas of hundreds and thousands km2) to local (with areas less than 1 km2). The lineament analysis based on the remote sensing studies in conjunction with geological and geophysical data has proved to be a useful tool for characterization of the regional and local geodynamic field. The used methodology includes analysis of the remote sensing data at different scale and defining the spatial distribution of the neotectonic indicators, the most important of which is a density of lineaments.
The article presents the results of the analysis of modern tectonics and geodynamics in the area of the Verkhnekamskoye potassium salt deposit (Russia, Perm Territory) - the largest in the world and best studied by various geological and geophysical methods, as well as Zhilyansky (Kazakhstan) and Tyubegatan (Uzbekistan) potassium salt deposits. At the Dekhkanobad mine (where at the end of 2012 there was a strong emergency influx of brines into the shafts) ten local geodynamic active zones were revealed using the results of a multi-scale photo-interpretation of satellite imagery. The largest zone was defined at the northern part of the Central Mine Field. After detail exploratory drilling, 11 local zones were allocated at this area. These areas were characterized by highest density of fractures and karstic features according to results of geological and geophysical studies, and in-mine observations. It was recommended to decrease the extraction within the potential hazardous zones and remain the additional safety pillars.