Hidden Ocean Brakes Limit Earthquakes on a Pacific Transform Fault
Scientists studying the Gofar transform fault off Ecuador found fractured, seawater-filled rock zones that act as dynamic brakes, repeatedly limiting ruptures to around magnitude 6 with a remarkably regular cycle. Seafloor sensors deployed in 2008 and again from 2019–2022 recorded bursts of small quakes in barrier regions before major ruptures and quiescence afterward, consistent with a dilatancy-strengthening mechanism driven by trapped fluids. The study suggests such barrier zones actively control rupture propagation on oceanic transform faults and could inform broader models of underwater earthquakes, though these faults lie far from shore communities.
