The application of Opposing Coils Transient Electromagnetics in the detection of karst subsidence area

Ground collapse caused by karst is both disastrous and covert. In order to forecast and control it effectively, a research area with strong karst collapse development was selected in this study, and a method that combines Opposing Coils Transient Electromagnetics with engineering geological drilling was used to verify the formation occurrence through the factors including buried depth of overburden, resistivity and isoline variation. The results of geophysical inversion maps and borehole information verification show that the Opposing Coils Transient Electromagnetics method can effectively identify the development of underground corrosion. Especially in the area where the conventional geophysical exploration methods may easily disturbed by the environmental factors, such method could achieve better application effect. Opposing Coils Transient Electromagnetics achieves effective forecast and prediction results in the developing areas of geological hazards and the karst-induced ground collapse, which could provide some theoretical and practical basis for research and analysis for similar circumstances.