THE RELOCATION AND SEISMOGENIC STRUCTURE OF THE DELINGHA EARTHQUAKE SEQUENCE OF 2003 IN QINGHAI
SUN Chang-hong1, QIAN Rong-yi1, XIAO Guo-lin2, MENG Xiao-hong1
1. Geo-detection Laboratory, Ministry of Education, China University of Geoscience, Beijing 100083, China;
2. School of Energy Resources, China University of Geoscience, Beijing 100083, China
The authors made initial location of the main shock of ML= 6.7 and aftershocks of totally 117 events with magnitude ML>1.0 for Delingha earthquake sequence till October 25, 2003, using the location intersection technique, and relocated 117 events using Double Difference Algorithm. It is known that the epicenter of the main shock was 37.566°N and 96.509°E, and the focal depth of the main shock was 13 km. The distribution of the aftershocks epicenters was consistent with the fault plane of 294° obtained from the focal mechanism of Harvard. The relocation results for the Delingha earthquake sequence clearly indicate that the seismogenic structure of the Delingha earthquake sequence is the NWW-SEE striking and NE-dipping Da Qaidam-Zongwulong Mountain modern active fault belt through the focal region. It is also indicated that the maximum horizontal main stress in this regional stress field is in the direction of about N24°E to N34°E .
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SUN Chang-hong, QIAN Rong-yi, XIAO Guo-lin, MENG Xiao-hong. THE RELOCATION AND SEISMOGENIC STRUCTURE OF THE DELINGHA EARTHQUAKE SEQUENCE OF 2003 IN QINGHAI. Geophysical and Geochemical Exploration, 2006, 30(1): 79-82.
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