Krüger Frank, Ohrnberger Matthias
Institute of Geosciences, University of Potsdam, Karl-Liebknecht-Strasse 24, 14476 Golm, Germany.
Nature. 2005 Jun 16;435(7044):937-9. doi: 10.1038/nature03696.
On 26 December 2004, a moment magnitude Mw = 9.3 earthquake occurred along Northern Sumatra, the Nicobar and Andaman islands, resulting in a devastating tsunami in the Indian Ocean region. The rapid and accurate estimation of the rupture length and direction of such tsunami-generating earthquakes is crucial for constraining both tsunami wave-height models as well as the seismic moment of the events. Compressional seismic waves generated at the hypocentre of the Sumatra earthquake arrived after about 12 min at the broadband seismic stations of the German Regional Seismic Network (GRSN), located approximately 9,000 km from the event. Here we present a modification of a standard array-seismological approach and show that it is possible to track the propagating rupture front of the Sumatra earthquake over a total rupture length of 1,150 km. We estimate the average rupture speed to be 2.3-2.7 km s(-1) and the total duration of rupture to be at least 430 s, and probably between 480 and 500 s.
2004年12月26日，苏门答腊北部、尼科巴群岛和安达曼群岛发生了矩震级Mw = 9.3的地震，引发了印度洋地区的毁灭性海啸。快速准确地估算此类引发海啸的地震的破裂长度和方向，对于限制海啸波高模型以及事件的地震矩都至关重要。苏门答腊地震震源产生的压缩地震波大约在12分钟后到达德国区域地震台网（GRSN）的宽带地震台站，这些台站距离该事件约9000公里。在此，我们提出了一种对标准台阵地震学方法的改进，并表明可以追踪苏门答腊地震的破裂前沿，其总破裂长度达1150公里。我们估计平均破裂速度为2.3 - 2.7公里/秒，破裂总持续时间至少为430秒，可能在480至500秒之间。
