| The structural state of overlying three-zones rock is significant in the process of coal mining under water. Therefore, it is foundation of coal mining and design to provide accurate information of caving zone and water flowing fractured zone before and after mining. Nowadays, a new method combining geophysics and drilling is more efficient than traditional drilling way to monitor coal mining process and identify demage situation of overlying rock after mining.This thesis proposes the new method of P wave and S wave seismic reflection to detect situation of rock in "Three-zone" area. To begin with, influencing factors and distributing regularity of water flowing fracture zone are analysed in term of overlying rock formation in the three-tone area. Furthermore, applying the basic principle of seismic wave propagation, this paper analyzes the process and influcing factors of data collection, discusses the basic rules and methods of contrasting the reflected waves, and sums up the characteristics and recognised signs of the fracture in the seismic time section. Thirdly, based on the detailed exploration in Daping coal mine, this paper clearly describes the process of exploring overlying three-zone rock by shear wave seismic reflection, and qualitatively analyses deforming trend of terrane under reservoir after mining. At last, according to the analysis and research of seismic data in the mining area, the paper analyses reflecting characteristics and recognising signs of faults, fractures and mined-out area in the time section. Consequently, the key technical problems are solved to detect underground fractures of mined-out area under reservoirs by means of S-wave seismic reflecting method on the iceCurrently, geophysical method is replacing drilling engineering partly. Especially in the area where it is diffucult to construct, it provdes a new type of method for the detection of overlying rock damage, and meanwhile affords referenced academic suggestions for similar research.
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