Abstract: Using the seismic data from north China since 2007, we calculate the earthquake clustering rate based on the nearest-neighbor distance algorithm. We study the characteristics of earthquake clustering of the seven seismic belts in north China,including Tanlu, Yanshan-Bohai, Hebei plain, Yinchuan-Hetao, Fenwei, Huai river, the lower reaches of the Yangtze river-Yellow sea, analyzing the characteristics of seismic activity in recent years. By analyzing the characteristics of earthquake clustering of Haicheng earthquake area, we consider that the earthquake sequence is weakening, and the occurrence of small earthquakes can be regarded as the background earthquake reflecting the regional stress state. Taking the Alxa M5.8 earthquake that happened on April 15, 2015 as an example, we study the characteristics of earthquake clustering before significant moderate-strong earthquakes in north China, and find that earthquake clustering rate will appear high value firstly, followed by a low value in the main earthquake zone, then the earthquake will erupt. This corresponds to the phenomenon of seismic activity intensity-quietude course before moderate-strong earthquakes, and this phenomenon has certain significance to determine the potential seismic hazard areas in the future.
WANG Peng,ZHENG Jianchang,LI Xiaohong et al. Study on the Characteristics of Earthquake Clustering in North China Based on the Nearest-Neighbor Distance[J]. jgg, 2017, 37(12): 1229-1233.