Characterizing Strong Shaking Hazard in Puget Sound Using Ambient Noise Seismology

Date: 4/24/2019

Time: 06:00 PM

Room: Grand Ballroom

Puget Sound contains several shallow sedimentary basins, comprised of unconsolidated deposits underlain by sedimentary rocks and set within hard crystalline bedrock. The basins underlie some of Washington’s most populous cities, and the region is subject to high seismic hazard. To characterize the shaking hazard in Puget Sound, we aim to understand how the seismic wavefield propagates within the basins. We extract this information from the ambient seismic wavefield. Using a newly developed set of correlation codes written in Julia, we cross-correlate ambient noise from all available short-period and broadband stations in the Puget Sound area in the 2010-2018 window. We present examples of all 9 components of the correlation tensor in the period band of 1-10 seconds. We characterize surface and body waves to investigate seismic amplification in the basins, and compare these amplifications with the current velocity model. We show preliminary dispersion curve measurements to extract Love- and Rayleigh-wave modes.

Presenting Author: Natasha Toghramadjian

Authors