Fig. 6

Model of the postseismic deformation after the Tohoku-oki earthquake (Agata et al. 2019). a Observed displacement of the land and seafloor stations shown by triangles and inverted triangles, respectively. The dashed-dotted line (A–A′) indicates the location of the vertical cross section. The dotted lines show the depth counter lines of the plate boundary. Coseismic slip is used from the simulation results of the megathrust earthquake cycle in the Tohoku region (Nakata et al. 2016). b Total displacement and viscosity of the viscoelastic medium 2.8 years after the Tohoku-oki earthquake. The distribution of effective viscosity in non-linear Maxwell elements immediately after the earthquake is shown with color. The observed displacements in A–A′ profiles, including stations MYGW and MYGI, are represented by the black arrows on the horizontal dashed lines. c Decomposed into viscoelastic relaxation and postseismic slip contribution. Elastic deformation caused by the postseismic slip and the contribution of viscoelastic deformation after 2.8 years. The observed displacement at the location of the purple circle shows an uplift. The uplift caused by the viscoelastic deformation at the location of the green circle is counteracted by the subsidence caused by postseismic slip