TECTONIC FEATURES AND ACTIVITY OF BINHAI FAULT ZONE IN TAIWAN STRAIT
Huang Zhao and Wang Shanxiong(Earthquake Administration of Fujian Province,Fuzhou 350003)
With the data of bottom topography,gravity,geomagnetism measurements and multichannel seismic detection, which the tectonic features and activity of the Binhai faults in Taiwan strait are obtained from fault investigations,are studied. The results show that the fault extends generally in the NE direction,whose NE end starts from the sea area to the east of Niushan island and its SW end is in the sea area of the eastern Xiongdi islet.With a total length of 500 km,it is a boundary fault between the South China continent and the sea basin of Taiwan Strait,which stretches out roughly along the isobath of 50-60 m.Its fault plane is almost upright and cuts through the crust.Under the action of the stress field with a principle compressive stress axis of NWW-SEE,the fault is predominated by right-lateral strike slip and it also has an obduction feature.With a sharp contrast of terrains on both sides,it is a recently active fault to control the differential sedmentation of Cenozoic stratum on both of its sides.The seismic activities on this fault are frequent and it is a fault zone with the most active seismicity in the Fujian coastal region.
【CateGory Index】： P315.2