关键词: 微动探测, 等值反磁通瞬变电磁法, 隐伏采空区, 视电阻率, 视横波速

Abstract: Concealed goaf is easy to cause geological disasters such as collapse and water gushing， which seriously restricts the safe production of mines. It is of great significance for mine engineering design and safety production management to accurately explore the spatial location，scale and occurrence state of concealed goaf. The conventional transient electromagnetic method is susceptible to mutual inductance in⁃ terference of the transmitting and receiving coils，and has defects such as blurred detection boundary，low accuracy of abnormal body shape recognition，and multiple solutions of stratum inversion. It is difficult to achieve fine detection of shallow goaf. Based on Daye Dahongshan Mine，the combined detection of shal⁃ low concealed goaf is carried out by using microtremor exploration and equivalent anti-magnetic flux tran⁃ sient electromagnetic method. By constructing a three-dimensional inversion model of apparent shear wave velocity and apparent resistivity，the two types of detection results can be mutually confirmed and comple⁃ mented，and the detection blind spots and multi-solution problems of a single geophysical method can be effectively avoided. The results show that there are 19 pit backfill areas and concealed goaf anomalies in the exploration range from the surface to-80 m，including 2 shallow backfill areas，4 goafs above -60 m，3 goafs between -60 m and -70 m，and 3 goafs deeper than -70 m. The low resistivity anomaly zone delin⁃ eated by the apparent resistivity of 300 Ω·m has a high spatial matching degree with the low wave velocity anomaly zone in the range of 300 ~ 1 000 m/s. The combined detection technology can realize all-round high-precision non-blind area detection of underground structure and physical parameters，and is suitable for fine exploration of shallow to medium-deep concealed goafs in complex mine sites. It has significant technical advantages and engineering promotion value.

Key words: microtremor detection, equivalent anti-magnetic flux transient electromagnetic method, concealed goaf, apparent resistivity, apparent shear wave velocity