Ground motion characteristics during the 2011 off the Pacific Coast of Tohoku Earthquake

The 2011 off the Pacific Coast of Tohoku Earthquake (MW9.0) caused severe damage not only because of the great tsunami, but also because of the ground motions. In the present paper, we report some details of the source mechanism and the ground motions during the earthquake, and discuss the ground motion characteristics related to the damage in the Tsukidate and Furukawa areas. Damage grades in Tsukidate, where the largest peak ground accelerations were observed, are not severe in comparison to those in Furukawa. The pseudo-velocity response spectrum for the ground motions observed in the Furukawa area is similar to that in the JR Takatori records for the 1995 Kobe earthquake.