[S13-6] Earthquake source mechanics VI

[S13-6-06] Variation of Earthquake Source Scenarios along the Nankai Trough for Hazard and Risk Assessment

^○Hiroe Miyake¹, Takashi Furumura², Takuya Nishimura³, Kimihiro Mochizuki², Kazushige Obara², Tomoya Harada², Naoya Sekiya¹ (1.CIDIR/III, The University of Tokyo, Tokyo, Japan, 2.ERI, The University of Tokyo, Tokyo, Japan, 3.DPRI, Kyoto University, Kyoto, Japan)

Historical Nankai Trough earthquakes show a large variation of source characteristics. Recent new observations reveal the diversity of earthquake sequence not limited to the coseismic rupture and segmentation. As a framework of the core-to-core collaborative research program of Earthquake Research Institute, the University of Tokyo and Disaster Prevention Research Institute, Kyoto University, we construct earthquake source scenarios along the Nankai Trough. To show the variation of scenario earthquakes, the logic tree is established based on expert opinions of geodesy, crustal structure from offshore to onshore regions, seismicity, and history for seismic and tsunami hazard assessment and related risk. The distributions of slip deficit, seamount, fault branch, slow earthquake, repeating earthquake, seismicity, and historical earthquake and tsunami source information are integrated with a weight ranging from 0 to 100%. The magnitude potential is controlled by the idea of partially coupled regions (Loveless and Meade, 2015) as a function of the coupling rate as well as overlaying the expert opinions. We validate seismic intensity and long-period ground motions for seismic hazard, and tsunami height and inundation area for tsunami hazard. The seismic and tsunami risk is assessed by population density, social and economic impact along the Pacific Ocean belt, and locations of nuclear and thermal power plants from the viewpoint of social science. We investigate the factor analyses to link the above mentioned earthquake scenarios, hazard, and risk.