Application of High-density Electrical Method in Geological Exploration of Goaf in Coal Mine

In order to evaluate the suitability and limitation of the application of high-density electrical method in geological exploration of coal mining areas, high-density resistivity meter was used in goaf geological exploration in a coal mine of Dongying, Shandong Province. Inverse analysis was conducted based on 6 stratigraphic sections, and verified by drilling work. The analysis results show that the resistivity of the non-goaf section increases gradually with the increase of depth, and has obvious stratification characteristics. The resistivity increases from 5 Ω·m at the surface to 200 Ω·m at 25 m depth. The resistivity distributions of the 3 goaf sections are extremely uneven, and there are cavity areas with abnormally low resistivity in the sections. The high-density electrical method can be used to delineate the general distribution and scope of goaf. Therefore, high-density electrical method is an efficient and convenient method with good suitability in the application of goaf exploration.