[U-08] Large-scale Projects in Earth and Planetary Science

[U08-03] New perspectives of subduction zone earthquake dynamics through experiments across-scales

*Masataka Kinoshita¹, Yoshio Kono², Eiichiro Araki³ (1.Earthquake Research Institute, University of Tokyo, 2.GRC/Ehime University, 3.IMG/JAMSTEC)

Keywords:Nankai Trough earthquake, Master plan, IODP, SPring-8, borehole observatory

Knowledge on subduction zone earthquake phenomena has considerably increased in the last decade. On the other hand, there are limits to seismological approach alone to comprehensively elucidate the earthquake mechanism in which phenomena that differ drastically in space and time, from earthquake nucleation/growth processes to its driving force. Steps to enable scientific earthquake forecasting should include; monitoring regional seismic/tectonic activity using networked observatories, sampling of and insitu measurement in seismogenic faults and plate materials through ultra-deep drilling, and reproduction/insitu-observation of fracture nucleation processes by high-pressure quantum-beam experiments. Through a close collaboration, we challenge a dynamic imaging of earthquake processes, and we have held a special session at the JpGU meetings since 2020. In 2020 we had 20 presentations, and in 2021 we had 8 presetations. This year, we focus on the state & property of seamount subduction and its possible consequence on seismicity.