Imaging the subsurface structures of the southern San Andreas fault using ambient noise and anthropogenic sources

Shuye Huang, Haoran Meng, & Yehuda Ben-Zion

Published September 11, 2022, SCEC Contribution #12385, 2022 SCEC Annual Meeting Poster #053 (PDF)

We present seismic imaging results for the subsurface structure (top ~100m) of the southern San Andreas Fault (SSAF) in the Coachella Valley. The results are based on ambient noise and signals generated by rail and road traffic, recorded by a 4-km long dense nodal array across the SSAF near the Thousand Palms Oasis Preserve. We detect frequent anthropogenic activities on rail and nearby roads, and use “quiet” noise data without such sources. We extract surface wave signals from Cross Correlation (CC) in the frequency band of 5-50 Hz of “quiet” noise data using standard ambient noise processing procedure. The results suggest an average Rayleigh wave velocity in this high frequency band of 300 m/s. In addition, we extract surface wave signals from the CC of the “coda” of car and of train signals, as the corresponding wavefields are well diffused. The preliminary results using a limited number of car and train events and are consist with those from the regular ambient noise analysis. This method is suitable for seismic arrays in urban areas and can be utilized for seismic imaging with high temporal resolution.

Citation
Huang, S., Meng, H., & Ben-Zion, Y. (2022, 09). Imaging the subsurface structures of the southern San Andreas fault using ambient noise and anthropogenic sources. Poster Presentation at 2022 SCEC Annual Meeting.

Related Projects & Working Groups
Seismology