汶川M_S8.0地震及余震序列重新定位

Relocation of the Wenchuan M_S8.0 Earthquake Sequence

从2008年5月12日汶川8.0级地震发震时刻起到2008年12月31日,四川省及其周边省区布设的区域台网、水库台网以及流动台共记录到10 000余次余震序列（M≥2.0）。我们采用双差定位法对主震及余震序列进行重新定位,得到7 000多个地震的重新定位结果。结果表明,余震分布带长约350 km。在西南部,余震沿龙门山后山、中央以及前山断裂分布;在中段,余震主要沿龙门山中央断裂分布;在北段,余震横穿青川—平武断裂分布。余震震源深度主要分布在10~20 km,重新定位后的平均震源深度为13 km。

From the origin time of May 12,2008,MS8.0 Wenchuan earthquake to Dec.31,2008,more than 10 000 aftershocks（M≥2.0） had been recorded by the seismic network in Sichuan and the surrounding provinces.In the paper,the main shock and more than 7 000 aftershocks were relocated using the double difference algorithm.The results show that the length of aftershock distribution is about 350 km.In the southwest,the distribution of aftershocks is along the Back-range,the Central and the Front-range of the Longmenshan fault.In the middle,the distribution of aftershocks is along the Central fault.In the North,the aftershocks distributed across the Qingchuanr-Pingwu fault.The depths of aftershocks mainly located in the 10~20 km,and the average depth of aftershocks is 13 km after relocation.