Session: Real-Time Monitoring and Warning with Fiber Optic Seismology
Type: Oral
Date: 10/8/2024
Time: 03:45 PM
Room: Stanley Park Ballroom
Toward Integration of DAS Arrays and Traditional Seismic Networks for Real-Time Earthquake Monitoring and Early Warning
Real-time earthquake monitoring and early warning relies on dense seismic networks with coverage around faults zones. Distributed Acoustic Sensing (DAS), a technology that turns fiber-optic cables into seismic arrays, can complement traditional networks where they lack sufficient observations. For example, detecting offshore earthquakes in real-time is challenging for traditional land-based seismic networks due to insufficient station coverage. Application of DAS to submarine cables has the potential to extend the reach of seismic networks and thereby improve real-time earthquake monitoring and Earthquake Early Warning (EEW).
We present an integrated methodology that uses DAS data and traditional seismic stations for EEW. We use data from the SeaFOAM DAS deployment (52 km-long submarine cable) in Monterey Bay, CA and the surrounding Northern California Seismic System (BK+NC networks). The region is seismically active with the nearby San Andreas Fault system, and the offshore San Gregorio Fault zones which the cable crosses. The algorithms to analyze the DAS data include a machine learning-based phase picking model (PhaseNet-DAS), a grid-search location method and an empirical magnitude estimation equation. This approach to analyzing the DAS data is compatible with the EPIC point source EEW algorithm currently used by ShakeAlert. We are therefore able to combine detection results from the DAS array with outputs from EPIC using the onshore seismic network. The preliminary results show that the integrated algorithms can reduce the detection time for offshore events and potentially increase warning time. We plan to implement the algorithms in the real-time EEW system and evaluate the performance. The proposed workflow can also accommodate the future integration of additional DAS cables to improve monitoring of specific fault zones in California.
Presenting Author: Yuancong
Additional Authors
Yuancong Gou yuancong_gou@berkeley.edu University of California, Berkeley, Berkeley, California, United States Presenting Author
Corresponding Author
|
Richard M Allen rallen@berkeley.edu University of California, Berkeley, Berkeley, California, United States |
Weiqiang Zhu zhuwq@berkeley.edu University of California, Berkeley, Berkeley, California, United States |
Taka'aki Taira taira@berkeley.edu University of California, Berkeley, Berkeley, California, United States |
Ivan Henson ihenson@berkeley.edu University of California, Berkeley, Berkeley, California, United States |
Angela Lux angie.lux@berkeley.edu University of California, Berkeley, Berkeley, California, United States |
Julien Marty jmarty@berkeley.edu University of California, Berkeley, Berkeley, California, United States |
Toward Integration of DAS Arrays and Traditional Seismic Networks for Real-Time Earthquake Monitoring and Early Warning
Category
Real-Time Monitoring and Warning with Fiber Optic Seismology
Description