Imaging the Garlock Fault Zone using distributed acoustic sensing

James W. Atterholt, Zhongwen Zhan, & Yan Yang

Submitted September 11, 2022, SCEC Contribution #12369, 2022 SCEC Annual Meeting Poster #050

Multi-scale fault zone structure largely controls the behavior of earthquake ruptures and encodes the long-term displacement history of the fault. Detailed images of subsurface fault zone structure fill an observational gap between surface mapping and low frequency tomography studies. But these images are difficult to obtain because they require dense deployments of seismic stations across the fault zone. Distributed acoustic sensing, an emergent technology that transforms fiber optic cables into dense arrays of strainmeters, provides the station density necessary to fill this gap at relatively low cost and effort. We use a distributed acoustic sensing array that extends from Ridgecrest, CA to Barstow, CA to image the Garlock Fault Zone, a major strike-slip fault zone in the Eastern California Shear Zone. The versatility of distributed acoustic sensing allows us to employ a multifaceted approach to imaging the fault zone that includes an active source experiment, ambient noise tomography, and travel-time anomalies from earthquakes. These approaches each provide unique constraints on the structure of the Garlock Fault Zone. This method-integrated imaging yields a detailed description of the fault zone’s lateral complexity and depth-dependent structure.

Key Words
distributed acoustic sensing, Garlock Fault Zone, fault zone imaging

Citation
Atterholt, J. W., Zhan, Z., & Yang, Y. (2022, 09). Imaging the Garlock Fault Zone using distributed acoustic sensing. Poster Presentation at 2022 SCEC Annual Meeting.


Related Projects & Working Groups
Seismology