Rupture Characteristics and Seismogenic Structures of the MS5.7 and MS5.6 Yiliang Earthquakes of Sep. 7, 2012
详细信息
- 责任者：Lü Jian (Earthquake Administration of Jiangxi Province ; Nanchang 330039 ; China) ; Zheng Xiufen
- 刊名：Chinese Journal of Geophysics
- 出版年：2013
- 卷期：56(8)
- 关键词：震源机制 ; focal mechanism ; 孕震构造 ; seismogenic tectonics ; 云南 ; Yunnan Province
- 页码：p.2645-2654
- 图表：8 illus., 3 tables, 38 refs.
- 分类号：0500
- issnNo：ISSN0001-5733
- isbnNo：CN11-2074/P
摘要
Based on the records of CSN and regional digital seismic networks,we obtained the focal depth and focal mechanism of the Ms5.7 and Ms5.6 Yiliang earthquakes of Sep.7,2012 with the "Cut and Paste"(CAP) method,and used the teleseismic depth phases like P,PP,and SP from IRIS records to determine the focal depth.Further,we analyzed the rupture characteristics and seismogenic structures of the Yiliang earthquakes combining with the earthquake epicenters,seismic intensity,and geologic settings in the region.Our result shows that the best double couple solution of the Ms5.7 event is 243°,62°,and 149° for strike,dip,and rake angles respectively,the other nodal plane is 349°,63°,and 32°;for the Ms5.6 event the solution is 241°,37°,162° with the other nodal plane of 346°,79°and 54°.We infer that both of the Ms5.7 and Ms5.6 earthquakes occurred on the NE striking Shimen fault and the focal depths of the events are about 6 km,the released seismic energy was concentrated in shallower crust which is an important reason for the serious seismic damage in the region.