煤田采空区地震CT探测数值模拟研究与应用

he existence of coal field goaf is the great human safety threat and precise goaf detection has become the major and urgent work to ensure mining safety. Presently, the common way of goaf detection is the combination of geophysical exploration and drilling method.This paper mainly introduces two effective geophysical techniques : the cross-hole CT and well-ground CT, as well as provides the basic principle of the two methods. Several numerical models which have different geometrys are established in order to test the effectiveness, reliability and accurateness of the techniques. The travel time of first break are picked accurately from simulated seismogram by the acoustic finite difference method under the cross-hole, Well-ground and the combined geometry respectively and then tomographic inversion processing is performed. Numerical simulation and analysis of field data indicates that seismic CT has high recognition ability, high accuracy of spatial location and size of imaging for goafs detection.So it can provide effective geological information for goafs.Accurate detection and has great significance of the goaf treatment.