Determination of underground voids in the surface of the earth section

One of the negative factors that affects the performance of various works on the Earth’s surface are voids in the surface part of the earth’s section. They are formed for various reasons. In most cases, these reasons are associated with irresponsible human activities. This can be excavation through adits, groundwater abstraction, or a breakthrough of underground utilities. In some cases, a disturbance in the ecological balance leads to the fact that the rivers go underground. Large areas of earth and sandstone are washed away. There is a danger of a collapse of the territory. Heavy rains are exacerbating this situation. These formed voids must be identified in a timely manner. Therefore, in places of their possible formation, it is necessary to constantly monitor the territory. The paper proposes an easy-to-use method for detecting these voids by imaging using refracted waves. For this, the collected data was processed using two different techniques. In the first case, the correlation of the first peaks on all seismograms is performed. This made it possible to obtain a depth-velocity section. The second method consists in reducing the travel time curves of the first refracted wave and obtaining a summarized seismic section. In this case, voids are distinguished by the loss of correlation of the axes of in-phase of the reduced time. This allows you to identify even small voids that form under the soil. With the deterioration of the ecological state, more and more voids are formed. To eliminate them, it is necessary to take prompt measures.