Assessing the suitability of the CRESCENT CVM0 for seismic hazard assessment in the Cascadia region

Aakash Gupta, Valerie J. Sahakian, Chih-Hsuan Sung, Norman A. Abrahamson, & Erin Wirth

Submitted August 30, 2026, SCEC Contribution #15584, 2026 SCEC Annual Meeting Poster #TBD

The Cascadia Subduction Zone (CSZ) poses a significant hazard to the Pacific Northwest, with the potential for earthquakes as large as magnitude 9 megathrust events. However, because of the relative quiescence of the Cascadia subduction zone during the era of modern seismic networks, constraining future ground motions with empirical ground motion models (GMMs) has been challenging. Recent research has shown promise in using physics-based ground motion simulations as a supplement in regions with limited data to constrain GMMs. However, these simulations require detailed and accurate seismic velocity models, with an understanding of how velocity model uncertainty propagates into hazard estimates.

In this study, we assess the suitability of the CRESCENT CVM0 (CRESCENT Generation 0 Cascadia Community Velocity Model) for this purpose. The model has been constrained using joint inversion of teleseismic receiver functions and ambient noise data, and is unique as it also provides uncertainty estimates, which are critical for seismic hazard assessment. With a carefully selected database of 100 earthquakes including interface, intraslab and crustal events, we generate synthetic seismograms up to 1Hz using the 3D wavefield simulation package SPECFEM3D. We then compare metrics computed for both real data and synthetic seismograms for each of the earthquakes, including peak ground acceleration (PGA), peak ground velocity (PGV), duration, and Fourier spectral amplitudes. We assign a score to each synthetic seismogram based on how it compares to its corresponding data record. Ultimately, we will make an assessment on the suitability of the use of the CRESCENT CVM0 in providing reliable synthetic seismograms for seismic hazard assessment in the Cascadia region.

Citation
Gupta, A., Sahakian, V. J., Sung, C., Abrahamson, N. A., & Wirth, E. (2026, 08). Assessing the suitability of the CRESCENT CVM0 for seismic hazard assessment in the Cascadia region. Poster Presentation at 2026 SCEC Annual Meeting.

Related Projects & Working Groups
Seismology