• 责任者：Cao Fengjuan (Earthquake Administration of Liaoning Province ; Shenyang 110034 ; China) ; Wang Liang
• 刊名：Seismology and Geology
• 出版年：2013
• 卷期：35(4)
• 关键词：地震序列 ; seismic sequence ; 孕震构造 ; seismogenic tectonics ; 辽宁 ; Liaoning Province
• 页码：p.842-852
• 图表：6 illus., 2 tables, 25 refs.
• 分类号：0500
• issnNo：ISSN0253-4967
• isbnNo：CN11-2192/P

     During the Gaizhou ML4.7 earthquake swarm sequence on February 2,2012,the energy release weakened gradually with time,accompanied with two obviously accelerated release processes.The double-difference location results show that the spatial distribution of Gaizhou earthquake swarm is mainly concentrated in the area between the Jinzhou Fault and the Yingkou-Haicheng Fault,spreading roughly in NW direction.The sequence showed a trend of migrating from Jinzhou Fault to YingkouHaicheng Fault,and the focal depths are distributed from 6km to 9km.The P-axis directions of focal mechanism of the two ML 4 earthquakes occurring on February 2 are distributed from 94 to 120 degrees,which coincide with the previous studies on the regional tectonic stress field.We could infer that Gaizhou ML 4.7 earthquake sequence on February 2 was caused by the strike-slip faulting of Jinzhou Fault under the action of NWW or near-EW regional stress field.But the P-axis direction of the two ML 4 earthquakes occurring on July 12 and November 1 turned to near NS,and according to the precise relocations,these two earthquakes had the trend of migrating to Yingkou-Haicheng Fault.It is inferred,therefore,that the two obvious stress releases are not only the result of slip of Jinzhou Fault,the Yingkou-Haicheng Fault also played a certain role.Combining with acoustic emission results,it can be further found that seismogenic structure of the ML 4.7 earthquake swarm in Gaizhou is the two en echelon faults,the NE-trending Jinzhou Fault and the Yingkou-Haicheng Fault.This earthquake swarm could be caused by joint action of the two faults.Meanwhile,it also indicates that there are signs of activity of both Jinzhou and Yingkou-Haicheng Faults under the action of the regional stress field.