The 11 March 2011 Tohoku Earthquake ruptured the interplate boundary off-shore of east Japan, with fault displacements of up to 40 m and a rupture duration of 150-160 s. W-phase inversion indicates a moment of 3.9 × 1022 N m (Mw 9.0) and a centroid time of 71 s. We invert teleseismic P waves and broadband Rayleigh wave observations with high-rate GPS recordings from Japan to characterize the rupture. The resulting rupture model begins with a steady increase of moment rate for the first 80 s, and a rupture speed of 1.5 km/s. Then the rupture expands southwestward at a speed of about 2.5 km/s. The model's primary slip is concentrated up-dip from the hypocenter, with significant displacement extending to the trench. The seaward location of large slip is consistent with estimates of the tsunami source area from regional and remote tsunami observations. The region with large slip is approximately 150-km wide by 300-km long, which is relatively compact compared with the 200-km wide, 500-km long aftershock region. The model's initial updip rupture expansion and the location of most slip updip of the hypocenter differs from P-wave array back-projections, which map high-frequency radiation along the downdip of the hypocenter, closer to the coast.
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机译：2011年3月11日的东北地震使日本东部沿海板块边界破裂，断层位移达40 m，破裂持续时间为150-160 s。 W相反转指示的力矩为3.9×10 22 N m（ M w 9.0），质心时间为71 s。我们使用日本的高GPS记录反演了远震 P 波和宽带瑞利波观测，以描述破裂的特征。最终的破裂模型从头80 s的矩速率稳定增加，破裂速度为1.5 km / s开始。然后破裂以约2.5 km / s的速度向西南扩展。模型的主要滑移集中在震源的上倾角，大量位移延伸到海沟。大滑坡在海中的位置与根据区域和偏远海啸观测对海啸源地区的估计一致。滑移较大的区域大约宽150公里，宽300公里，与200公里宽，500公里长的余震地区相比相对紧凑。该模型的初始上倾破裂扩展和震源的最大滑动上倾的位置与 P 波阵列反投影不同，后者沿震源下倾绘制了更靠近海岸的高频辐射。
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