Crustal Dynamics

Grant-in-Aid for Scientific Research
on Innovative Areas, MEXT Japan

Crustal Dynamics Unified understanding of intra-island deformation after the great Tohoku-oki earthquake.

C01 (Modeling Group) Development of models for deformation and fault slip processes in the island arc crust (Group leader: Bunichiro Shibazaki)

C01_1E

Based on the results obtained by other research teams, we will develop models of deformations of whole island arc to specific areas that can explain observed stress and strain, and furthermore develop the generation of large inland earthquakes. Particularly, after the 2011 Tohoku-oki earthquake, significant post-seismic deformation is proceeding in the island arc crust and mantle. The forecasting of such post-seismic deformation is an urgent issue. Therefore, (1) we will develop the non-uniform rheological structure model based on the petrological structure, geofluid distribution, temperature distributions and experimental results and model the deformation and stress field over the whole island arc due to the generation of the 2011 Tohoku-oki earthquake. Afterwards, analysis of observed crustal deformation is conducted to clarify how the deformation is progressed in the island arc. (2) Then, the deformations and stress field will be modelled by taking into account the detailed non-uniform rheological structure for target areas such as Akita and Tottori where absolute stress is planned to be estimated based on the dense seismological observation, as well as Onikobe where detailed geofluid distribution has been clarified. (3) Furthermore, the model of fault slip process that considers the friction and flow processes will be developed based on experimental results. By the above mentioned research, we aim to understand the deformation process of both whole island arc and specific areas and then the generation process of large inland earthquakes.