Re-examination of the Tsunami Source Model of the 2011 off Pacific coast of Tohoku Earthquake

Abstract

Various tsunami source models of the 2011 Tohoku Earthquake (Mw9.0) have been proposed by using each set of observation data. However, although some of the observation data can be explained with these models, it could not well explain the observation data of GNSS and the coastal tsunami inundation height distribution together. In this study, we conducted tsunami source inversion analysis using offshore tsunami waveform, terrestrial / oceanographic geodetic data, tsunami inundation height data and GNSS data with a realistic plate shape model proposed in Yokota et al. (2017). The result suggests that the slip Miyagi off is started after 1 minute of generation and its reach Iwate off along the trench with slow motion until 4 minutes.