A rapid response Distributed Acoustic Sensing (DAS) array after the 2019 Ridgecrest earthquakes

Zhongwen Zhan, Zefeng Li, Zhichao Shen, Yan Yang, Ethan F. Williams, Xin Wang, Jack B. Muir, Andrew Klesh, & Martin Karrenbach

Published August 12, 2020, SCEC Contribution #10455, 2020 SCEC Annual Meeting Talk on TBD

Distributed Acoustic Sensing (DAS) is a new technology that can convert kilometers of pre-existing fiber optic cable into a dense seismic array. DAS has demonstrated strong potential in both seismicity monitoring and subsurface imaging. Within a few days of the 2019 Ridgecrest M7.2 earthquake, we managed to gain access to multiple pre-existing telecommunication cables around the source region and deployed four DAS instruments to establish a network with over 6000 channels. With the data, we are able to (1) detect 5 to 10 times more aftershocks than the conventional catalog; (2) observe highly variable ground shaking intensity in space from the moderate-size aftershocks; (3) derive a high-resolution near-surface seismic velocity model that can explain the main features of the site amplifications. Our Ridgecrest experience demonstrates that DAS will become a useful tool in earthquake rapid response, if we prepare the equipment, fiber access, and training ahead of future big earthquakes.

Citation
Zhan, Z., Li, Z., Shen, Z., Yang, Y., Williams, E. F., Wang, X., Muir, J. B., Klesh, A., & Karrenbach, M. (2020, 08). A rapid response Distributed Acoustic Sensing (DAS) array after the 2019 Ridgecrest earthquakes. Oral Presentation at 2020 SCEC Annual Meeting.

Related Projects & Working Groups
Seismology