Misattributed tsunami 2: The Tōhoku Japan (Mw 9.0) 2011.3.11 earthquake

Like the tsunamis that accompanied the 2010 Maule (Chile) and the 2004 Sumatra-Andaman and 2005 Nias earthquakes, the tsunamis associated with the Tōhoku, Japan (Mw 9.0), earthquake of 11 March 2011 may owe more to slip on superficial faults on the sea floor than to the megathrust itself. The pattern of shallow aftershocks during the 24 h immediately following the main shock suggests that the crucial structures include faults in the upper plate, in the accretionary wedge landwards of the trench and on the outer rise. Seafloor geodetic observation could thus usefully contribute routinely to local hazard preparedness.