Numerical Study on Tsunami Inundation Induced by Tokai, Tonankai and Nankai Massive Earthquakes

This study numerically investigates tsunami inundation characteristics due to Tokai, Tonankai and Nankai massive earthquakes on the coast of the Pacific Ocean and three major bays in Japan, Tokyo Bay, Ise Bay and Osaka Bay. As a result, the inundation depth in some areas along the Pacific Ocean enlarged with the increase of the magnitude of earthquake, but there was little difference in terms of inundation area. Flat areas below sea level were strongly damaged by tsunami inundation in the case that all riverine and coastal structures were completely destroyed just after the earthquakes. On the other hand, the areas were recognized to be slightly damaged in the case that all the riverine and coastal structures fully function. Thus, it is necessary to take hard countermeasures against tsunami disaster in areas below sea level. Furthermore, the comparison of historical tsunamis and numerical results suggests that tsunami induced by Tokai, Tonankai and Nankai massive earthquakes with a scale of M9 is important to be discussed.