根据IRIS全球地震台网15个台的长周期地震仪记录的P波资料,用远场体波地震图反演震源破裂过程的方式,研究了2010年4月14日玉树MS7.1地震震源破裂,并与震后调查地表破裂带做了对比。结果表明:玉树地震在总体上是一次单侧破裂事件,破裂从初始破裂点(即震源位置)开始向东南方向展开,破裂离震源20km处开始贯穿至地表,沿走向方向延伸了约50km,最大滑移量达2m。这些结果与震后考察得到的地表破裂带的特征十分吻合。
Based on the digital teleseismic P-wave seismograms recorded by 15 long-period seismograph stations of the global seismic network,source rupture process of the April 14,2010 Yushu MS=7.1 earthquake is studied by a inversion method,and compared with surface rupture zone which was investigated after the earthquake.The result shows that the earthquake is a unilateral rupture event on the whole.The source rupture initiated at the hypocenter(33.2°N,96.6°E,focal depth 10 km),and propagated to the southeast at first.The rupture broken though the ground surface departed from 20 km of the epicenter,it extended 50 km along strike,the maximal slip is 2 m.These results are coincide with the investigated feature of the surface rupture zone.