Fig. 1.

Dense ocean-bottom seismic and tsunami stations (indicated by circles) are being constructed off the Pacific coast of northeastern Honshu, Japan (e.g. Uehira et al., 2012; Kanazawa, 2013) and dense seismic stations (indicated by squares) are being operated on land (Okada et al., 2004; Obara et al., 2005) by the National Research Institute for Earth Science and Disaster Prevention (NIED).