Assessing Distributed Acoustic Sensing Ground Motion Estimation with Co-located Seismometer Network for Earthquake Early Warning

This research expands on work in the field of Distributed Acoustic Sensing (DAS), a new technology that exploits unused optical fiber infrastructure for seismic strain sensing. When deployed on telecommunication cables, particularly offshore, the method has the potential to significantly enhance the coverage of Earthquake Early Warning (EEW) systems. However, while current EEW systems are designed to receive measurements of peak ground acceleration (PGA) from conventional seismic stations, the correlation between DAS amplitudes and ground motion is still not fully understood. There exists a need for more observations to validate this relationship before DAS technology can be included in EEW operations. In this study, DAS peak strain-rate (PSR) values are converted into ground motion predictions by estimating the apparent wave speed using a slant-stack approach. These predictions are compared with real measurements of PGA from co-located seismic stations from the Community Seismic Network to observe correlation and evaluate the accuracy of the method. Results provide new insight into the relationship between DAS amplitudes and ground motion and demonstrate the potential for DAS measurements to augment existing EEW systems.