DISCUSSION ON SEISMOLOGICAL PRINCIPLE OF GEOLOGIST

Geologist thinks that fault is the surface expression of focus. The paper discusses how to predict strong earthquake by using information of quantitative research on active faults on the basis of the principle. Prediction of places where strong earthquake occurs depends on the investigation of fault activity. Especially,interpretation of air photo and field investigation of faulted landform is emphasized to get the latest active time of fault. The fault which was active during Late Quaternary is recognized to have larger seismic potential in the future. The intensity of strong earthquake has close relations with the length of active fault and the rupture accompanied with earthquake. It is in direct proportion,which was confirmed by a lot of historical earthquakes and recent earthquakes occurring in the whole world. Prediction of time of strong earthquake needs to get the recurrence interval and the elapse time of latest activity on different fault zones. Average interval of strong earthquake may get from the ratio between active rate and the offset accompanied with earthquake on the fault. Besides,trench investigation to get times of paleoearthquakes on different faults is very important for distinguishing individual character of seismic-activity on different fault zones. A lot of information on research of active fault and recognition from Japan and Professor T. Matsuda is quoted in the paper. At last the paper briefly reviews the development of research on active fault in China.