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Title: Real-Data Testing of Distributed Acoustic Sensing for Offshore Earthquake Early Warning
Abstract We present a real-data test for offshore earthquake early warning (EEW) with distributed acoustic sensing (DAS) by transforming submarine fiber-optic cable into a dense seismic array. First, we constrain earthquake locations using the arrival-time information recorded by the DAS array. Second, with site effects along the cable calibrated using an independent earthquake, we estimate earthquake magnitudes directly from strain rate amplitudes by applying a scaling relation transferred from onshore DAS arrays. Our results indicate that using this single 50 km offshore DAS array can offer ∼3 s improvement in the alert time of EEW compared to onshore seismic stations. Furthermore, we simulate and demonstrate that multiple DAS arrays extending toward the trench placed along the coast can uniformly improve alert times along a subduction zone by more than 5 s.  more » « less
Award ID(s):
1848166
PAR ID:
10497456
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
SSA
Date Published:
Journal Name:
The Seismic Record
Volume:
3
Issue:
4
ISSN:
2694-4006
Page Range / eLocation ID:
269 to 277
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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