THE TIME DISTRIBUTION CHARACTERISTIC OF EARTHQUAKES IN NORTH CHINA AREA AND ITS SIGNIFICANCE

In this paper, the time distribution characteristic of earthquakes in North China area is studied. As a consequence, it is found that there is a certain regular distribution between time interval of earthquakes in North China area and their occurrence rates. For example, for the earthq uakes in large North China area, at Ms≥5.0 1gN△_T=2.33-0.39·|△_T|at Ms≥6.0 gN△_T=1.84-0.41·|△_T|This paper also discusses the problem of predicting seismic risk by above mentioned empiric formulas.