Shear Wave Velocities in the San Gabriel and San Bernardino Basins, California
Abstract
We construct a new shear velocity model for the San Gabriel, Chino and San Bernardino basins located in the northern Los Angeles area using ambient noise correlation between dense linear nodal arrays, broadband stations, and accelerometers. We observe Rayleigh and Love waves in the correlation of vertical (Z) and transverse (T) components, respectively. By combining Hilbert and Wavelet transforms, we obtain the separated fundamental and first higher mode of the Rayleigh wave dispersion curves based on their distinct particle motion polarization. Basin depths constrained by receiver functions, gravity, and borehole data are incorporated into the prior model. Our 3D shear wave velocity model covers the upper 3–5 km of the crust in the San Gabriel, Chino and San Bernardino basin area. The Vs model is in agreement with the geological and geophysical cross-sections from other studies, but discrepancies exist between our model and a Southern California Earthquake Center community velocity model. Our shear wave velocity model shows good consistency with the CVMS 4.26 in the San Gabriel basin, but predicts a deeper and slower sedimentary basin in the San Bernardino and Chino basins than the community model.
Additional Information
© 2023. American Geophysical Union. The authors thank Zhe Jia for help with the ambient noise correction code and helpful discussions, and Tom Brocher for providing the borehole data. The authors thank all the volunteers who helped with deploying the dense nodal arrays. This research was supported by the National Science Foundation awards 2105358 and 2105320. The BASIN project was partly supported by U.S. Geological Survey awards GS17AP00002 and G19AP00015, and Southern California Earthquake Center awards 18029 and 19033. Nodal instruments were provided by Incorporated Research Institutions for Seismology (IRIS), Portable Array Seismic Studies of the Continental Lithosphere (PASSCAL), University of Utah, Louisiana State University, and the University of Oklahoma. Data Availability Statement: The final Vs model can be downloaded from http://doi.org/10.22002/D1.20248 (Y. Li et al., 2022). All the node and temporary broadband data used in the study are scheduled to be available at the IRIS DMC in 2023. The permanent strong motion and broadband data are available from the Southern California Earthquake Data Center (SCEDC).Attached Files
Supplemental Material - 2023jb026488-sup-0001-supporting_information_si-s01.pdf
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Additional details
- Eprint ID
- 122545
- Resolver ID
- CaltechAUTHORS:20230726-216909500.3
- EAR-2105358
- NSF
- EAR-2105320
- NSF
- GS17AP00002
- USGS
- G19AP00015
- USGS
- 18029
- Southern California Earthquake Center (SCEC)
- 19033
- Southern California Earthquake Center (SCEC)
- Created
-
2023-08-11Created from EPrint's datestamp field
- Updated
-
2023-08-14Created from EPrint's last_modified field
- Caltech groups
- Division of Geological and Planetary Sciences, Seismological Laboratory