SEISMICITY AND THE RECENT FRACTURING PATTERN OF THE EARTH CRUST IN CHINA
Ding Guoyu Li Yongshan
The fracturing of the crust, being in action recently in China and in more extensive regions, appears to be characterized by some kind of a regular network. This feature may be confirmed by historic and recent seismieity, geologic and geomorphologic evidences, as well as the diagnostic distribution of linear structures identified from the satellite images.The seismic events of continental China correspond only partly to old tectonic structures. In general they are distributed along some definite directions, mainly NE and NW, occasionally NS and EW as well, forming a zonal and conjugated pattern. As a result, there appears on a large scale a regular network of the recent crustal fracturing.The events which took place intermittently along these fracture zones were in general correlated each other in accordance with a definite regularity both in space and time. In most cases the stronger earthquakes occurred right in the intersections of these crust-fracturing zones.The very feature that the recent crust-fracturing appears in a network pattern, can be used to account for the correlation between individual earthquakes on a large scale. The study of the crust-fracturing pattern is therefore a highly significant topic for deciphering the stress field of recent structure and in earthquake prediction.