LAUSR

S U M M A R Y We investigate slip-distribution models of the 2011 Tohoku earthquake, with a particular focus on diffracted tsunamis and uplift-induced waves along the backarc region of the Japanese Island Arc. The 2011 Tohoku earthquake produced a large amplitude tsunami that diffracted around Kyushu Island before reaching Korea. At the same time, this earthquake coseismically induced short-period small-amplitude sea waves in the East Sea. We performed tsunami simulations using seven fault models of the Tohoku earthquake to examine whether the models can accurately reproduce the observed waveforms in the open sea of the western Pacific Ocean, the South Sea of Korea, and the coast of the East Sea. For each fault model, we investigate tsunami features due to geomorphological characteristics of the Korean Peninsula in the Korea offshore. To determine which slip distribution model shows a good performance in the tsunami simulations, we set three criteria; the delay time between observations and synthetic waveforms, the normalized mean residual, and the normalized RMS misfit. Depending on the study region, all models show varying degrees of accuracy. The fault dimensions and the amount of slip have a larger effect on the RMS misfit then the slip distribution patterns of the fault models for observations along the Korean coast and the western coast of Japan.