Tiny Earthquakes Reveal Hidden Faults Under Northern California

Andy Fell — January 15, 2026 - 11:54am

By tracking swarms of very small earthquakes, seismologists are getting a new picture of the complex region where the San Andreas fault meets the Cascadia subduction zone, an area that could give rise to devastating major earthquakes. The work, by researchers at the U.S. Geological Survey, the University of California, Davis, and the University of Colorado Boulder, is published Jan. 15 in Science.

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Tiny Earthquakes Reveal Hidden Faults Under Northern California