CRUSTAL STRUCTURE OF THE CENTRAL PART OF THE NORTH CHINA PLAIN AND THE HSINGTAI(邢台) EARTHQUAKE (Ⅱ)
TENG JI-WEN WANG GUO-CHENG LIU DAO-HUNG HSING JI-EUN LIANG WEN-DOUXu SHI-LIN et al.
The seismic wave field of artificial explosions at the most destructive area of the Hsingtai earthquake, M = 7.2, of March 22, 196(?) was very complex. The kinematic and dynamic characteristics of the such seismic waves show that there exist along the profile many deep faults which cut the profile into five blocks, and the fault planes usually extend to the Mohorovicic discontinuity and to the solid medium of the upper mantle, while in the most destructive area the structure has a more spe-cific character.Here, the apparent velocity V*, the apparent period T*, the layer boundary velocity Vd, and the energy absorption coefficient a* of the medium vary anomalously. It is a fracture zone of fault complex with a width of 10-20 km.Under the epicentral area of the earthquake, there exist two groups of deep and large faults, intersecting at this point. The local horizontal dislocation reaches about 4 km in the medium at the focal depth, where the upper mantle rises.