On the earthquake of March 11, 2011 near the northeastern coast of Honshu Island

The paper addresses the interpretation of the location, type, and size of the source for the earth-quake of March 11, 2011. The source—a subvertical reverse fault trending in the azimuth of ∼25° along the island arc—is located in the middle part of the Pacific slope of Honshu Island, between 38°–38.5°N and 35.5°N. The length of the source, about 350 km, approximately corresponds to a magnitude ∼8.7 earthquake. In the north, the source is bounded by a sublatitudinal reverse fault, which generated an earthquake with magnitude 7.2–7.5 in 1978. On this segment of the Pacific slope of Honshu Island, there are probably another one or a few other large seismic sources, which are still latent. They are longitudinal reverse faults, which are comparable in scale with the source of the March, 2011 earthquake. The recurrence period of the maximal earthquakes in such sources is more than 1000 years.