Presentation Information
[U09-02]Tsunami Sediment along the Nankai Trough and Nuclear Power Plants
*Makoto OKAMURA1 (1.Science Research Center)
Keywords:
mega-quake,Nankai Trough,tsunami sediment,nuclear power plant
We know well interplate megathrust earthquakes have been occurred repeatedly through several decades to centuries. Based on this common knowledge, huge earthquakes and tsunamis must be occured within a period of several thousand years. We research on tsunami sediment from lacustrine deposits along the Nankai Trough for prehistoric Nankai Trough Earthquake. As a result, large tsunami has been occurred 300 years interval through past 6,000 years. The Hoei Earthquake, AD1707 was the biggest tsunami through last millennium as mentioned after ancient manuscripts. Nevertheless, over the Hoei Earthquake tsunami sediments were found in several cores collected from lacustrine deposits. However, we only have poor knowledge about these interplate earthquakes through millennium. Actually, the Fukushima Accident after the Kashiwazaki, we cannot evaluate even small-sized earthquake (Mw6.8), and 3.11 tsunami. We, seismologists and engineers, said "out of image" just after 3.11 off Tohoku District Earthquake. Never say "safe or safety" again about future earthquake and tsunami related nuclear power plants.