Purpose. The purpose of this work is definition of potentially ecologically-hazard and karst-chasm zones and prediction of karst development near the Skhidnytsia-Pisochne highway on the area of mine No.2 of Stebnyk potassium deposit by electroprospecting method, namely time domain electromagnetic method (TDEM). Methodology. The research was carried out using the TDEM method in the modification of “the contour in the contour”. To study the upper part of the cross-section down to 100 meters, the digital equipment for electroprospecting “Stage” was used. For information about the depths of 50-100 meters and up to 300-400 meters, a digital electric station "Impulse 3M" was used. Field observations by TDEM methodically consisted of three phases which included: sounding on parametric wells, thus clarifying electrical parameters of the geological environment; observations along defined profiles; and creation resulting of geoelectric cross sections with the reference to the lithology of the working area. Results. In the northern part of research area within the sediments of the gypsum-clay cap anomalous electrical conduction zones are identified. They are associated with filtration-suffusion processes. As well an anomaly was defined in the southern part of the area in the Vorotyscha suite sediments at depths greater than 100 meters, which was associated with the formation of a depression funnel. Originality. The possibility of the TDEM method application for the study of karst-chasm processes on the territory of the Stebnyk potassium deposit was investigated. For the first time, using the electrical prospecting methods an estimation of the state of geological environment within the mine field No. 2 of the Stebnyk potassium deposit on the area of the Skhidnytsya-Pisochne highway was made. It is shown that the TDEM method in the complexization of two types of devices with different measurement depths allowed detailed diagnosis in the geological environment in the range of depths from 10 to 400 m with the allocation of zones of abnormal electrical resistivity, which are associated with the suffusion-filtration processes. Practical significance. Accordingly to the results of electromagnetic observations on the area of the highway Skhidnytsya-Pisochne in the location of the mine field No.2 of the Stebnyk potassium deposit, the zones covered by the filtration-suffusion processes are defined. These zones are the primary objects that should be the subject of close attention for further monitoring of karst-chasm processes, and the fact of their availability should be taken into account when making administrative decisions by the authorities on the expediency of transferring the location of the highway and other infrastructure.
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