A Thinking for Decade Seimicity

Starting with the viewpoint of the overall seismicity,it is showed that the 4 earthquakes with Ms≥7 0 from 1966 to 1976 in North China are the overall chain activity in a major system with the successive order in time and the zonal and segmental relation in space based on the seismicity data since 1900.A superficial view was proposed from this,it was showed that there will be difficult to reoccur the same magnitude earthquakes in the active region of main body bounded by the 4 earthquakes at Xingtai,Bohai,Haicheng and Tangshan.And some“diffraction seismicity” in Shanxi seismic belt and Yinshan-Yanshan seismic belt will develop the common activity in North China,the earthquake activity with Ms6 0 in future will be seen as the peak activity in the region.