Search

We investigate in this study the impact of the Tohoku-Oki earthquake on Eastern China, and particularly focus on postseismic relaxation processes. We first invert for postseismic slip on the fault plane based on the GPS measurements of GEONET in Japan. Then, we use a layered rheological model to theoretically investigate the deep viscoelastic relaxation process. The Tohoku-Oki mainshock produced significant strain changes in Eastern China, dominantly east-west-oriented extension with a level close to or higher than the tectonic strain rates at the east border of China. The strain due to the postseismic stress relaxations has similar patterns as those produced by the mainshock, but with smaller magnitudes. The Tohoku-Oki earthquake impacts Eastern China for decades, but dominantly in the first 2-3 years after the mainshock and caused an apparent displacements and decrease of seismicity rate in Northeast China. For a long-term of 100 years, the Tohoku-Oki earthquake produces about 10 % of the tectonic strain rates in Eastern China, due to viscoelastic relaxation at the deep depth. [ABSTRACT FROM AUTHOR]