S wave velocity model from ambient-noise surface-wave tomography in the San Gabriel and San Bernardino Basins

Yida Li, Robert W. Clayton, & Zhe Jia

Published August 14, 2019, SCEC Contribution #9565, 2019 SCEC Annual Meeting Poster #054

The velocity structure of San Gabriel basin and San Bernardino Basin in the northern part of the Los Angeles region are of great importance for the earthquake hazard evaluation, as they have the potential to focus seismic energy into the Los Angeles Basin. However, the velocity model in these regions were not as well developed as the Los Angeles Basin due to the lack of oil exploration. Since 2017 several lines of seismic dense arrays have been deployed in the northern basins, and we exploit these newly acquired data to develop a 3D shear wave velocity model using ambient noise cross-correlation. Both correlation between dense array and SCSN broadband stations and intra-dense-array correlations are included in our analysis. We also take advantage of both Love wave and Rayleigh wave’s fundamental mode and first higher mode to better constrain our model. The preliminary results gave us a self-consistent lateral variation, and a sharp increase at the bottom of our model domain presumably correlated with the bottom of the basin.

Key Words
San Gabriel Basin, San Bernardino Basin, noise correlation

Citation
Li, Y., Clayton, R. W., & Jia, Z. (2019, 08). S wave velocity model from ambient-noise surface-wave tomography in the San Gabriel and San Bernardino Basins. Poster Presentation at 2019 SCEC Annual Meeting.

Related Projects & Working Groups
Seismology