THE INVERSE TSUNAMI PROBLEM FOR SYMMETRIC ISLANDS OF SIMPLE SHAPE

Abstract

The problem investigated in this paper is that of estimating the deep water signature of a tsunami based on an observed marigram in the immediate vicinity of an island. The basic assumption is made that the incident tsunami in deep water is represented by a plane wave but that its signature in time at a fixed point in deep water is unknown. This implies that the distance of the earthquake epicenter is large compared with the horizontal scale of the island at its base on the ocean floor. The present study is limited to the linear theory for long waves and accordingly its application requires that the observed water level signatures be at locations where non-linear effects and dispersion are minimal. The method is numerical.