On tsunami propagation

Abstract

The propagation of the Alaskan tsunamis of 1946 and 1964 has been studied using an iterative algorithm designed to handle continuous optimal problems. The results of calculations for the 1946 tsunami to Sitka demonstrate its capabilities and show that the great circle does not always furnish reliable approximations to the travel time and path. Calculations for the 1964 tsunami permit the description of its propagation and the plotting of the ray paths to locations along the American coast. In the southwest Pacific, most of the wave train was dispersed by the complex bathymetry northeast of Australia but some wave energy passed through the Fiji basin into the Tasman Sea. The reflection of the wave by the Undulla Deep explains the late arrivals in New Zealand and the remarkable tide record from Macquarie Island.