S/P Amplitude Ratios with Distributed Acoustic Sensing

Robert J. Skoumal, James W. Atterholt, Andrew J. Barbour, & Jeanne L. Hardebeck

Submitted September 7, 2025, SCEC Contribution #14403, 2025 SCEC Annual Meeting Poster #TBD

Distributed Acoustic Sensing (DAS), which transforms a fiber optic cable into an array of high frequency strainmeters, has the potential to help us characterize earthquakes with a dense sampling of measurements. While earthquake focal mechanisms are frequently determined using P-wave polarities and S/P amplitude ratios with inertial seismometers, the dense sampling of DAS over potentially large portions of the focal sphere can aid our solutions. Here, we consider ~200 regional earthquakes and thousands of S/P measurements on a DAS cable collocated with a network of inertial seismometers near Arcata, California. We demonstrate the S/P ratio measurements made on DAS are similar to those made on the inertial seismometers and can be used to constrain focal mechanism solutions.

Key Words
DAS, focal mechanism, S/P Ratio

Citation
Skoumal, R. J., Atterholt, J. W., Barbour, A. J., & Hardebeck, J. L. (2025, 09). S/P Amplitude Ratios with Distributed Acoustic Sensing. Poster Presentation at 2025 SCEC Annual Meeting.

Related Projects & Working Groups
Seismology