Slip distribution of the 2011 off the Pacific coast of Tohoku Earthquake inferred from geodetic data

Abstract

We analyze geodetic observation data associated with the 2011 Tohoku Earthquake to estimate coseismic and early postseismic fault slip distribution on the Pacific plate interface. The maximum slip and the moment magnitude of the main shock are about 60 m and Mw 9.0, respectively. The location of the main slip patch is complementary to the source region of large earthquakes at least for those which have occurred during the last 100 years, and the maximum slip was corresponded to a release of stress accumulation for about 700 years Source regions of the 1936, 1938, and 1978 earthquakes are considered to have been re-ruptured in the 2011 main shock, where the slip amount was significantly smaller than the main patch.