Gravity Anomaly From Satellite Gravity Gradiometry Data by GOCE in Japan Ms9.0 Strong Earthquake Region

The great tsunami and secondary disasters caused by Ms9.0 strong earthquake occurred in northeastern Japan on March 11, 2011 has attracted widely public attention from all over the world. In this paper, gravity anomaly is calculated in the region between east longitude 132°and 145°, north latitude 35°and 50° by using satellite gravity gradiometry data observed by GOCE(Gravity field and steady-state Ocean Circulation Explorer). The computed gravity anomaly is compared with the topographical data and location of seismic activity in this region. The results show that gravity anomaly has great consistency with the regional tectonic distribution and Ms9.0 strong earthquake occurred in the steep gravity gradient zone. The spatial distribution of the gravity anomaly has obviously correspondence with extrusion action from the Pacific plate.