2009年9月29日萨摩亚群岛地区地震破裂过程快速反演

Fast inversion of the rupture process of 2009 September 29 Samoa Islands region earthquake

运用地震破裂过程快速反演方法,在2009年9月29日萨摩亚群岛地区地震发生后,采用全球地震台网(GSN)的宽频带地震资料,快速反演了这次地震的破裂过程,并于震后3.5小时内得出了这次地震破裂过程的反演结果.结果表明,这次萨摩亚群岛地区地震的破裂过程具有如下基本特征:①矩震级约为MW8.0;②地震主要破裂持续时间约为138s;③滑动量在断层面上的分布比较复杂,整个地震破裂包含至少2个滑动量较大的区域;④这次地震基本上是一次单侧破裂事件,破裂主要朝向西北方向.

The rupture process of 2009 September 29 Samoa Islands region earthquake was obtained by inverting the broadband seismic data of Global Seismographic Network （GSN） based on the fast inversion method of earthquake rupture process within 3.5 hours after the earthquake occurrence. It is found that the Samoa Islands region earthquake has several basic characteristics as follows： ① Moment magnitude is about MW8.0;② Rupture duration time is about 140 s;③ The static slip distribution is complex and the whole rupture process at least contains 2 slip concentrated patches;④ Overall the earthquake is mainly a unilateral rupture event with the rupture propagating northwesternward.