SCEC Award Number 18223 View PDF
Proposal Category Individual Proposal (Integration and Theory)
Proposal Title Towards a 3D Shear-Wave Velocity Model of Central California
Investigator(s)
Name Organization
Gregory Beroza Stanford University Lise Retailleau Stanford University Aurelien Mordret Massachusetts Institute of Technology
Other Participants
SCEC Priorities 4a, 3a, 4c SCEC Groups Seismology, CXM, GM
Report Due Date 03/15/2019 Date Report Submitted 05/08/2019
Project Abstract
 We have used ambient-field correlation functions to develop an isotropic shear-wave velocity model. The model we obtain agrees with previous lower-resolution velocity models of the region (e.g., Shapiro et al., 2005; Lin et al., 2008) and we are in the process of analyzing the local misfits to assess if radial anisotropy is necessary to provide a satisfactory fit to the dispersion curves. Preliminary analysis shows that models in the Central Valley tend to systematically converge toward too fast or too slow Love wave dispersion depending on location – hinting at presence of radial anisotropy in the upper crust.
Intellectual Merit This study have developed a 3D shear wave velocity structure for California. Future work will explore whether the data require anisotropy of S-wave velocities.
Broader Impacts The study will contribute the accuracy of physics-based ground motion simulations.
Exemplary Figure Figure 3: Model of the 3D shear velocity result of the inversion for slices at different depths.