Abstract: During coal mining, unknown geological changes can easily cause accidents in safe coal production.YTR(D) Rayleigh was used to detect in advance coal seams in Da'anshan coal mine. Detection data indicated that 5 of 12 abnormal zones exposed by mining corresponded to geological changes, and the rest was due to difference of lithological interface or bedding surface. The detection results can be used as basis for safe production in coal mines.