Science Daily October 17, 2023
An international team of researchers (USA – Caltech, industry, Chile) provided 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. They constrained earthquake locations using the arrival‐time information recorded by the DAS array and earthquake magnitudes were estimated directly from strain rate amplitudes by applying a scaling relation transferred from onshore DAS arrays. According to the researchers their 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. They also simulated and demonstrated that multiple DAS arrays extending toward the trench placed along the coast could uniformly improve alert times along a subduction zone by more than 5 s… read more. Open Access TECHNICAL ARTICLE
(a) Map of the study area in Chile… Credit: The Seismic Record (2023) 3 (4): 269–277