Seismological Laboratory, Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA.
Science. 2011 Jun 17;332(6036):1421-5. doi: 10.1126/science.1206731. Epub 2011 May 19.
Geophysical observations from the 2011 moment magnitude (M(w)) 9.0 Tohoku-Oki, Japan earthquake allow exploration of a rare large event along a subduction megathrust. Models for this event indicate that the distribution of coseismic fault slip exceeded 50 meters in places. Sources of high-frequency seismic waves delineate the edges of the deepest portions of coseismic slip and do not simply correlate with the locations of peak slip. Relative to the M(w) 8.8 2010 Maule, Chile earthquake, the Tohoku-Oki earthquake was deficient in high-frequency seismic radiation--a difference that we attribute to its relatively shallow depth. Estimates of total fault slip and surface secular strain accumulation on millennial time scales suggest the need to consider the potential for a future large earthquake just south of this event.
2011 年矩震级(Mw)9.0 的日本东北-关东地震的地球物理观测结果允许沿俯冲带特大地震进行探索。该事件的模型表明,同震断层滑动的分布在某些地方超过 50 米。高频地震波的震源描绘了同震滑动的最深部分的边缘,并不简单地与最大滑动位置相关。与 2010 年智利Mw8.8 级马乌莱地震相比,东北-关东地震缺乏高频地震辐射,这一差异我们归因于其相对较浅的深度。在千年时间尺度上对总断层滑动和地表长期应变积累的估计表明,需要考虑在此次事件以南发生未来大地震的可能性。