STUDY ON DEEP SEISMIC REFLECTION PROFILE ALONG NORTHERN MARGIN OF NORTH CHINA PLATFORM

In order to study the crust structure of northern margin in North China Platform , we did a deep reflection seismic experiment in the western Liaoning Province, China. It shows a 2D seismic profile in study area using a nearly vertical reflection method. The survey line starts from Jianchang County, and ends at Xingcheng in Liaoning. The survey line is 100km long and extended in 33° North West. We identified 5 main reflected waves, whose two way travel time are around 6s, 6.5s, 7.5s, 8s and 10.4s. We described and analyzed geophysical characteristics of these reflected waves, and compared data with other results from neighborhoods. Then we conclude that the crust in survey area is divided into upper and lower crust, and the upper has no obvious reflection, the lower shows "sunken" feature; 10.4s TWT signals from Moho are observed with high signal-to-noise ratio and good resolution, it tells us the depth of Moho here is roughly 30km and Moho in the east end near Bohai is 600m shallower than the other side; and Moho in the study area is composed of some thin layers with different velocity and thickness.