Based on the earthquake catalogue of the Ms=8. 0 Wenchuan Earthquake from Sichuan Earthquake Information Network, China Earthquake Networks Center, China Earthquake Information Nets and National Earthquake Scientific Data Sharing Center, the temporal and spatial distributions of seismic sequence of 1 613 aftershocks with Ms≥3 from May 12th, 2008 to March 1st, 2010 were analyzed. The results showed that the aftershocks of the Ms = 8. 0 Wenchuan Earthquake could be divided into seven stages, and the 18 days after principal shock should be the alert time for the strong aftershock; the b value of seismic sequence was 0. 751, which confirmed the view ' the greater magnitude, the higher b value' ; the p value of seismic sequence was 1. 117 , which was considerable to global seismic attenuation rate; the distribution of aftershocks expanded along northeast direction of Longmen Mountain Fault, and was obviously zonal; the distribution of aftershocks could be divided into south, middle and north sections, and the south section was the starting part of earthquake rupture while the later aftershocks distributed mainly in the north section; focal depths were 10-40 km, especially 10-20 km, which showed that the Longmen Mountain Fault were mainly in the upper crust and the focal depth gradually decreased from south to north; focal depth expanded, and the distributions of aftershocks in south section were obviously pulsed, and the distribution in middle section expanded respectively from 15, 30. 25 km focal depths to deep and shallow at the same time, and the distributions in north section were flexural and were about 15 km steadily in the end.%基于四川防震减灾信息网以及中国地震台网中心、中国地震信息网、国家地震科学数据共享中心提供的汶川8.0级地震目录资料,对2008年5月12日至2010年3月1日共1 613次3.0级及以上余震的地震序列进行了时空分布分析.结果表明:汶川8.0级地震的余震大致可分为7个阶段,主震后18天应列为大地震强余震发生的警戒时间；地震序列的b值为0.751,印证了在类型相同的情况下主震震级越大b值越高的观点；地震序列的p值为1.117,与全球地震衰减速率相当；汶川地震的余震分布主要沿龙门山断裂走向北东向扩展,且具有明显分区性,自南向北分为南、中、北3区段,南区为地震起始破裂段,地震后期余震则主要分布在北区；震源深度分布在10～40 km,集中在10～20 km,表明龙门山断裂主要发生在中上地壳,且震源深度由南向北呈现逐渐变浅的趋势；震源深度扩展,南区呈明显脉冲状,中区主要是依次由15、30、25 km深度向深、浅层同时扩展,北区余震深度分布呈“乙”字型,最后稳定在15 km左右.
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