Modeling Tsunami Wave Heights Around the Pacific Basin from an Izu-Bonin Mariana Earthquake and the Potential for Rewriting Earthquake History

Session: Understanding Non-Traditional Seismic Tsunami Hazards [Poster]
Type: Poster
Date: 4/28/2020
Time: 08:00 AM
Room: Ballroom
Description: 

The Izu-Bonin Mariana (IBM) subduction zone is a nearly 3000-km long oceanic-oceanic convergence zone with no instrumental record of large subduction-zone earthquakes. This lack of large earthquakes along with the subduction style has led some to speculate that the IBM does not produce large earthquakes. The same behavior was also speculated for the northern Japan and Cascadia subduction zones, which has since been proven false. We utilize tsunami simulations to produce estimates of wave heights at locations around the Pacific Basin that have the potential for written records dating back to the 1500s (such as cities like Concepcion, Chile; Lima, Peru; and Acapulco, Mexico). We use GeoClaw (v5.6.0) with adjoint-guided refinement level flagging to simulate Pacific Basin crossing tsunamis generated from three fault regions within the IBM. The resulting simulated wave heights are assessed to determine whether a large IBM tsunami could have been noted in historical records; possibly extending the aseismic behavior of the IBM further back in time. We use these estimates to create wave height “fingerprints” that will help distinguish between tsunamis generated from different Pacific Basin fault sources. The results of this study could lead to a re-evaluation of the earthquake history within the IBM.

Presenting Author: Rachelle Reisinger

Authors