Earthquake and Tsunami Scenarios as Basic Information to Prepare Next Nankai Megathrust Earthquakes

Abstract

This paper describes earthquake and tsunami scenarios as basic information for preparing for the next Nankai megathrust earthquakes. Models to clarify the size of the Nankai megathrust earthquake and changes in occurrence intervals, simulations using such models, and simulations of crustal deformations and tsunamis based on the simulations were employed. This paper re-examines past earthquakes and tsunamis, the possibility of slightly larger earthquakes and tsunamis, their sizes, the necessity of countermeasures against subsidence caused by earthquakes in the Inland Sea, the possibility of the Nankai earthquake occurrence before the Tokai (Tonankai) earthquake, and the possibility of the triggering of the Nankai earthquake by the Hyuga-nada earthquake.