The application of the methods of high density resistivity method and transient electromagnetic to detecting coal mining goaf and to inspect grouting effect

Starting from the dangers of geological calamities induced by coal mining goaf and the practical significance of coal mining goaf detection and controlling,this paper summarizes the application status of geophysical methods in coal mining goaf detecting and analyses the resistivity difference along coal mining goaf.Based on brief introduces the principle of high density resistivity method and TEM.combined with a case study in Xinjiang Province,the application effects of high density resistivity method and TEM in coal mining goaf detection are analyzed.The results shows that there are distinct resistivity difference between coal mining goaf and host rocks,high density resistivity method can get good effect to detect coal mining goaf no deeper than 120m.while TEM is useful to the goaf buried in 100m to 350m deep.The feasibility of high density resistivity method to infect grouting effect of coal mining goaf is discussed via an example.