Repurposed fibre optic cables show promise as seismometers

This is the claim of scientists at the California Institute of Technology (CALTECH), who have measured a magnitude 6 (M6) earthquake, determining the time and location of four individual asperities that led to the rupture. Their work is detailed in Nature.

California is crisscrossed by thousands of miles of fibre optic cables that deliver digital services to its residents. Professor of Geophysics Zhongwen Zhan and his team used a 100km section of cable to precisely understand the complex mechanics behind a particular 2021 earthquake, suggesting that access to more cables would enable improved understanding of earthquake physics and better earthquake early-warning systems.

"If we can get broader coverage to measure seismic activity, we can revolutionise how we study earthquakes and provide more advance warning," Zhan said in a statement. "Though we cannot predict earthquakes, distributed acoustic sensing will lead to a better understanding of the details underlying how the earth ruptures."