A PRELIMINARY STUDY OF THE STRUCTURE OF THE EARTH'S CRUST FOR THE PROFILE FROM SUIXIAN TO XIAN
DING YUN-YU(The Seimological Bureau of Shanxi Province,Xian) CAO JIA-MIN(Chengdu College of Geology)HUANG CHANC-LIN(The Seismological Bureau of Shanxi Province, Xian)JIANG GUO-FANG(The Seismological Bureau of Sichuan Province, Chengdu)
In this paper, the data of deep seismic sounding (DSS) for the profile from Suixian to Xian have been studied. The phase for primary discontinuities in the Earth's crust have been discussed; The "Layered inversion" and the "Composite inversion" from observed travel tirrfes give a crustal model of three layers. The thickness and average velocity of the Earth's crust are about 34km and 6.33 km/s respectively. The apparent velocity of Pn refracted from Moho discontinuity is about 8.1km/s.It has been found that the lower crust is alternately constituted from high-velocity layer and low-velocity layer. The velocity of the High-velocity layer is 7.39 km/s.The relieves of the boundaries in the Earth's crust fer this profile have been constructed and, some-relative questions discussed.