Determination of the fault model consistent with the tsunami generation of the 1964 Niigata earthquake

Abstract

A fault model was investigated for the Niigata Earthquake of June 16, 1964, and one consistent with the tsunami generation was obtained, using tide gauge records and inundation heights. Main parameters in the model are as follows: reverse fault with a dislocation of 6±1 m, strike of N22°E, and dip angle of 45° in the direction of N68°W, having a dimension of 55 km in length and 20 km in width. In this process it was found that the sea level ratio of the initial wave to the reflected one is sensitive to a dip angle. It is noticeable that the dimension is small and the dislocation is large, but the seismic moment is nearly equal in comparison with proposed models for this event. It is important to investigate each parameter of the fault model by applying it to the tsunami generation.