Research Center for Prediction of Earthquakes and Volcanic Eruptions, Graduate School of Science

The stress field of the north-east Japan is east-west compression. The eastern margin of the Japan Sea (EMJS) is known as many earthquakes occurred. It is thought that the reverse fault slip is caused by the stress field with the maximum compression axis approximately east-west direction. We review distribution of focal mechanisms and the stress field to find spatio-temporal changes. Also, we focus on the large to moderate-sized earthquakes to estimate the relation ship between fault planes and stress field.