RECALL OF A MID-SHORT TERM PREDICTION BEFORE THE TANGSHAN EARTHQIAKE

In 1976, the author and his colleagues drew 5 seismic risk regions by seismic nodal line, among the others, in Ⅲ region occurred the Helingeer M 6.3 earthquake in April, 1976.Combining with the stress and geomagnetic data, it was predicted that a relatively large earthquke might occur in July and Augustin 1976 in northern part of North China.The purpose of this paper is for the 20th anniversary of the Tangshan earthquake.