The average coal thickness of the Tangjiahui mine in the Zhungeer mining area in Inner Mongolia was 19 m, which was an extra-thick coal seam. In order to prevent water inrush from the sloping collapsed column in the coal seam, the water-sinking accident occured through the construction of the trough wave seismic exploration face. The results of the exploration showed that the transmission slot wave method had high precision for the detection range of the collapse column in the coal seam. Through the later verification of the entire working face, a long-axis collapse column was found, indicating that the groove wave earthquake was also applicable in the extra-thick coal seam.