Citation

Ide S, Baltay A, Beroza GC. Science 2011; 332(6036): 1426-1429.

Affiliation

Department of Earth and Planetary Science, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033, Japan.

Copyright

(Copyright © 2011, American Association for the Advancement of Science)

DOI

10.1126/science.1207020

PMID

21596957

Abstract

Strong spatial variation of rupture characteristics in the M(w) 9.0 Tohoku-Oki megathrust earthquake controlled both the strength of shaking and the size of the tsunami that followed. Finite-source imaging reveals that the rupture consisted of a small initial phase, deep rupture for up to 40 s, extensive shallow rupture at 60 to 70 s, and continuing deep rupture lasting over 100 s. A combination of a shallow dipping fault and a compliant hanging wall may have enabled large shallow slip near the trench. Normal faulting aftershocks in the area of high slip suggest dynamic overshoot on the fault. Despite prodigious total slip, shallower parts of the rupture weakly radiated at high frequencies, whereas deeper parts of the rupture radiated strongly at high frequencies.

Language: en