Abstract: In order to accurately find out the hidden dangers in the hidden goaf of metal mines and improve the technical basis for mine disaster prevention and control，taking Longqiao Iron Mine as the re⁃ search object，the application of joint detection of controlled source audio magnetotelluric method (CSAMT) and natural source surface wave microtremor exploration is carried out. On the basis of combing the geological and geophysical characteristics of the mining area，the parallel profile observation system is used to synchronously collect resistivity and surface wave signals. The underground electrical structure and shear wave velocity distribution are obtained by data inversion，and the comprehensive interpretation of anomalies is completed by combining geological and borehole data. The results show that the two geophysi⁃ cal methods are highly complementary and the detection accuracy is reliable. In this study，nine goaf-af⁃ fected areas in the early mining section above -370 m are delineated，including six filled goafs and three incompletely filled goafs. The goaf in the mining area shows a typical binary geophysical response law. The filled goaf shows a low-low resistance anomaly，and the incompletely filled goaf shows a low-high resis⁃ tance anomaly. The overlying bedrock of the goaf is generally broken locally，and the mining effect has a continuous disturbance effect on the stability of the surrounding rock. Practice has proved that the com⁃ bined exploration of CSAMT and microtremor can effectively identify the spatial position and filling state of goaf，and form a refined goaf detection technology system suitable for metal mines，which can provide technical reference for disaster management in mining areas and safety exploration of similar mines.

Key words: goaf detection, controlled source audio magnetotelluric method, microtremor method, re? sistivity, shear wave velocity