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利用江西南昌遥测台网和临时台网资料,借助于主地震相对定位法,对2005年11月26日江西九江-瑞昌MS5.7地震序列进行了重新定位,分析了该序列的破裂过程。这次地震的余震震中呈线性分布,约沿北西37°,与美国哈佛大学给出的主震震源机制解中的N35°W节面和北西向的洋鸡山-武山-通江岭断裂的走向基本一致,震中位于该断裂的东南端。这次地震破裂扩展过程主要发生在2005年11月30日19时前,其后平稳。主震发生在余震分布区的西北端部,似乎表明本次地震为单侧破裂,破裂向东南方向扩展。震后4小时内震源深度由浅到深变化,之后逐渐稳定在15 km左右。破裂过程大致可分为两个阶段:第1个阶段是从主震到2005年11月26日16时22分0.8秒,破裂尺度为13.8 km,历时约7.54小时,平均破裂速度约为50.8 cm/s;第2个阶段是从2005年11月29日11时35分21.7秒到2005年11月30日19时57分58秒,破裂尺度为17.9 km,历时约32.4小时,平均破裂速度约为15.4 cm/s。整个破裂过程扩展了31.7 km,平均破裂速度约为22 cm/s,前一阶段速度明显高于后一阶段,破裂是减速的。
Based on the data from Nanchang, Jiangxi Province and the temporary network, with the help of the relative positioning method of main earthquakes, the J5-Ruicheng MS5.7 earthquake sequence in Jiangxi Province was relocated on November 26, 2005, and the rupture process of the sequence was analyzed. The aftershock epicenter of the earthquake presented a linear distribution about 37 ° northwest with the N35 ° W nodal plane in the focal mechanism solution of the main shock given by Harvard University and the NW-trending Yangjishan-Wushan-Tongjiangling fault The trend is basically the same, with the epicenter located at the southeast end of the fault. The earthquake rupture expansion occurred mainly before 19:00 on November 30, 2005, and then stabilized. The main shock occurred at the northwestern end of the aftershock distribution, which seems to indicate that the earthquake was unilateral rupture and ruptured to the southeast direction. The focal depth changed from shallow to deep within 4 hours after the earthquake and then gradually stabilized at about 15 km. The rupture process can be roughly divided into two stages: the first stage is from the main shock until 16:22:08 on November 26, 2005 with a rupture scale of 13.8 km, which takes about 7.54 hours and the average rupture speed is about 50.8 cm / s; the second stage is from 21:35:11:35 on November 29, 2005 to 19:57:58 on November 30, 2005, the rupture scale is 17.9 km, which takes about 32.4 hours and the average rupture speed is about Is 15.4 cm / s. The entire rupture process has been extended by 31.7 km with an average rupture rate of about 22 cm / s. The velocity of the previous stage was significantly higher than that of the latter stage, and the rupture was decelerated.