PRELIMINARY RESULTS OF THE INVESTIGATION OF THE CRUSTAL STRUCTURE OF THE SOUTH-CENTRAL PART OF SHANSI PROVINCE
Institute of Geophysics, Academia Sinica
In this study preliminary results are presented for the investigation of the crustal structure of the South- central part of Shansi Province by use of the time-term method, applied to the material obtained during several industrial explosions carried out in Chang-an, Dai Hsien and Taigu. An adaptation of the method is made for those explosions of which the origin times are not known. The velocity just below the M-discontinuity is found to be 7.95±0.04 km/sec. Assuming an average velocity of 6.4 km/sec, for the crust, the time-terms for 41 locations were obtained, whence the corresponding depths of the M-discontinuity were computed by inversion. The relation between these and the seismicity or mechanism of earthquakes in this area is briefly discussed.