RESTUDY ON HYPOCENTRAL LOCATION AND SEISMOGENIC TECTONIC OF THE JIUJIANG-RUICHANG MS5.7 EARTHQUAKE SEQUENCE,JIANGXI PROVINCE |
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| Authors: | LUO Li Lü Jian ZENG Wen-jing TANG Lan-rong |
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| Affiliation: | Earthquake Administration of Jiangxi Province, Nanchang 330039, China |
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| Abstract: | We collected seismic records of 228 ML≥1.0 Jiujiang-Ruichang MS5.7 earthquake sequence from Dec.26, 2005 to Jun. 30, 2006. By using double-difference method combined with waveform cross-correlation, those earthquakes were relocated and finally the accurate source parameters of 224 earthquakes were obtained. The errors are about 0. 5km in horizontal and less than 2km in vertical direction, respectively. It was found that the depth of earthquake sequence concentrates in 8~14km range, and the epicenters are distributed along both NW and NE direction, and dominantly along NW direction. Combined with the focal mechanism, the distribution direction and the tectonic setting, we infer that the rupture of the NW-trending fault caused the MS5. 7 main shock, and then the rupture probably encountered an asperity and triggered the MS4. 8 strong aftershock. The NE-trending fault came into a seismically quiet period by stress adjustment in a short time, while the NW-trending fault released stress for a long time which caused a series of aftershocks. The MS5. 7 main shock is caused by the NW striking Yangjisshan-Wushan-Tongjiangling Fault and the MS4. 8 aftershock occurred on the NE striking Liujia-Fanjiapu-Chengmenshan Fault. |
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| Keywords: | Jiujiang-Ruichang earthquake Hypodd method waveform cross-correlation seismogenic structure |
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