Study on Characteristics of the 1700 Cascadia Earthquake Tsunami along the Pacific Coast of Japan

Abstract

To investigate the propagation of the 1700 Cascadia tsunami, we simulated a trans-pacific tsunami using the linear long-wave and dispersive models. The model results suggest that the scattering of the tsunami excited by the Emperor Seamounts Chain causes the delay of the maximum tsunami along the Pacific coast of Japan. We further conducted simple numerical tests focusing on resolutions of bathymetry data to develop the modeling of the scattering waves. The results reveal that less than 2-min grid size of bathymetry data is required to represent the tsunami scattering waves. We simulated the 1700 Cascadia tsunami and compared the measured data with the computed tsunami heights. The computed results approximately consist with the measured data of "Lower height estimate". On the other hands, the doubling the fault model of Cascadia earthquake is required to conform the computed data to the measured data of "Upper height estimate".