FY 2001

Simulation of paleotsunamis in Puget Sound, Washington

Koshimura, S., A.L. Moore, and H.O. Mofjeld

In Proceedings of the International Tsunami Symposium 2001 (ITS 2001), Session 7-7, Seattle, WA, 7–10 August 2001, 761–773, (on CD-ROM) (2001)

This study aims to reproduce the tsunami that occurred 1100 years ago in Puget Sound reported by recent paleoseismological studies, using a finite difference model based on nonlinear shallow water theory. The study refines the estimates of run-up height, flow depth, and current velocity at these sites made by Moore (1993) and Dinkelman and Holmes (1993), using a high-resolution model that explicitly allows for coastal flooding and drying. The model is also used to estimate the spatial patterns of tsunami propagation and coastal inundation throughout Puget Sound for this earthquake scenario. When combined with existing field observations of paleotsunamis and ground movement, the simulations will help to constrain the earthquake mechanism. They will also help guide the search for additional geological evidences of this event.