Abstract:In view of the fact that the travel time of reflected compressional wave passing through vertical fracture medium varys azimuthally,a new method is developed which derives fracture strike from the compressional wave data of some seismic lines having different azimuths. In general circumstances,fracture medium has expression 2£一8J0,so that fracture strike estimated by inversion is an unique solution. Correctness of this method has been proved by the inversion results of travel times of reflected compressional waves in both two group of orthogonal seismic lines and four oblique seismic lines of a fracture medium model.