UC Riverside Method Pinpointed Kamchatka Megaquake Spot

UC Riverside geophysicists built an algorithm that identified the exact section of the Kamchatka fault where a massive earthquake later ruptured.

Geophysicists Gareth Funning and Axel Periollat of the University of California, Riverside have developed a method that identifies where Earth's biggest earthquakes are most likely to occur. Rather than predicting timing, the approach locates where stress has been quietly building along major faults. In a test described in a Geophysical Research Letters paper, the model highlighted the exact section of the Kamchatka subduction zone in eastern Russia where a massive earthquake later struck, an event that prompted tsunami warnings along the US West Coast in 2025.

The Kamchatka Peninsula experienced giant earthquakes in both 1952 and 2025, yet the two events behaved differently, with the more recent rupture producing a much smaller tsunami. The researchers say this suggests the shallowest portion of the fault slipped less than it did during the 1952 event. The result is also striking because the locked region was identified from a relatively limited data set before the earthquake occurred, confirming the technique has real potential despite its sparse inputs.

The method focuses on subduction zones, where one tectonic plate slides beneath another and generates the world's largest earthquakes, including those exceeding magnitude 8.5. Using GPS measurements of subtle ground movement, the researchers' algorithm identifies locked fault patches known as asperities, which resist motion until enough stress builds to trigger a major rupture. According to phys.org, the team compared their inferred high-locking probability regions against previously proposed asperity and coupling models for the Kamchatka megathrust, and the rupture occurred where strain had accumulated. Periollat told UC Riverside News, "Seeing it work so well confirmed that this approach has real potential."

The team is now applying the approach to other major subduction zones in Japan, Mexico, New Zealand and the Pacific Northwest, and is exploring whether it can help understand California faults. According to phys.org, the researchers note that Funning sees a parallel in the Bay Area's Hayward Fault, which has both creeping and locked sections much like subduction zones. Better observations will be essential, since offshore faults where measurements are scarce remain hard to monitor. Both outlets emphasize the method cannot predict when quakes will strike or how large tsunamis will be, and Funning stresses there is no substitute for preparation.