On the relevance of using a complex combination of NIEMFE and EM methods in forecasting rock deformation

The article deals with the problem of studying rock deformation, its forecasting and simulation in the forms of folds and faults of the Earth’s surface. The subject of study is Stebnytske potassium salt field in the Subcarpathia and the surrounding territories. A number of methods has been used for the study, namely: investigations of a natural pulse electromagnetic field of Earth (NIEMFE) and the electromagnetic induction logging (EM). The physical background of these methods are in the relation between the level of rock deformation and the intensity of the electromagnetic field (for NIEMFE method), as well as the level of strength reduction caused by increased water saturation of the rock, creation of electrically resistant salt cake (for the EM method). The results of the study are depicted by maps of intensity of NIEMFE and geoelectrical cross sections. The methods correlate in some respects and complement each other by their comprehensiveness: the NIEMFE method helps detect the existent and potential deformational faults, whereas EM method determines their depth. Thus, the combination of the two methods should be deemed to be suitable not only for proving the actual existent deformations and their state but also, due to the factual geodesic data, for forecasting the further folds and faults that often become a reason of emergency situations and accidents.