Observations and Modeling of Tsunamis from Genesis to Inundation Using Contemporary Methods

Loading...
Thumbnail Image

Date

2025-02-24

Authors

Santellanes, Sean

Journal Title

Journal ISSN

Volume Title

Publisher

University of Oregon

Abstract

This dissertation explores broadly the science of tsunamis from genesisto inundation. Tsunami science has been able to produce accurate forecasts of tsunami first arrival and propagation from advancements in deep ocean monitoring and high resolution bathymetry and topography. However, it remains in its infancy compared to its sister disciplne — seismology, owing to the lack and sparse instrumentation in the offshore, deep ocean environment. In addition, the lack of understanding of how turbulence and anthropogenic structures affects inundation leaves the most destructive part of the tsunami life cycle remarkably unconstrained. This dissertation seeks to understand and better constrain several aspects of the tsunami life cycle. In this dissertation, I present an analysis of the tsunami source of the 2022 Hunga Tonga global tsunami, showing from open ocean and coastal sea level stations, the coupled atmospheric conditions that propagated the tsunami globally. Further, I show that the background open ocean tsunami spectrum, vital for understanding tsunami amplification from open ocean to the coast, can experience changes due to atmospherically induced infragravity waves. Next, I present an analysis of the 2020 Sand Point tsunami source. This work shows a novel method for including open ocean instrumentation with geodetic and seismological data to produce finite fault models capable of detecting ”hidden” subduction zone events. Finally, I present an analysis of the differences of inundation between homogeneous and heterogeneous tsunami sources along the Cascadia Subduction Zone. This work highlights the importance of using heterogeneous tsunami sources for understanding how inundation may affect the anthropogenic environment. This work may lay the groundwork for probabilistic- based tsunami evacuation rather than relying on deterministic, homogeneous tsunami sources. This dissertation includes previously published (unpublished) co-authored material.

Description

Keywords

Earthquakes, Geohazards, Seismology, Tsunami

Citation