Science
Scientists Develop Tool to Pinpoint High-Risk Zones for Major Earthquakes
Researchers at UC Riverside have created a new technique for locating where the world's largest earthquakes are most likely to strike, providing a potentially valuable resource for disaster readiness efforts in high-risk seismic zones. Instead of forecasting when an earthquake will occur, the method pinpoints areas along major faults where stress has accumulated, allowing scientists to identify likely rupture sites.
The research, led by UCR geophysicists Gareth Funning and Axel Periollat, was published in Geophysical Research Letters. The scientists study how the planet's surface gradually shifts as tectonic plates become locked together prior to rupturing. According to Funning, faults quietly build up strain for years before an earthquake makes headlines, and this buildup can be measured.
The technique concentrates on subduction zones, areas where one tectonic plate slides underneath another. These zones are responsible for the planet's most powerful earthquakes, some exceeding magnitude 8.5, and frequently trigger catastrophic tsunamis. By analyzing GPS data that tracks minute ground movements, the team built an algorithm capable of detecting locked fault segments where energy is being stored. These sections, called asperities, function like friction points that hold firm until accumulated stress becomes strong enough to unleash a major earthquake.
Before a significant earthquake hit Russia's Kamchatka Peninsula, the team had already flagged a locked region beneath it using their model. Although the method could not forecast when the quake would happen, the rupture ultimately occurred precisely where the model indicated strain had built up. Periollat noted that despite working with a fairly limited data set, the team had a sense of where strain was concentrating, and seeing the model succeed confirmed its potential value.
The study also uncovered differences in how earthquakes in the same location can unfold. Kamchatka experienced major earthquakes in both 1952 and 2025, yet the more recent event produced a considerably smaller tsunami. This suggests that the shallow portion of the fault slipped less in 2025 than it had decades earlier.
The researchers caution that their approach cannot forecast tsunami magnitude or the exact timing of an earthquake. Still, being able to narrow down high-risk fault locations could strengthen long-term hazard planning. The team is now expanding their model to other major subduction zones, including those in Japan, Mexico, New Zealand, and the Pacific Northwest, each of which presents unique challenges, such as fault movement that releases energy gradually instead of through sudden rupture.
The scientists are also examining whether the method could apply to fault systems in California. Funning pointed to the Hayward Fault in the Bay Area, which contains both creeping and locked segments similar to subduction zones, and said the team is investigating which portions are most likely to produce future earthquakes.
Expanding the method's use will depend on improved observational data. While land-based GPS stations offer useful information, there are far fewer measurements available offshore, where many dangerous faults are located beneath the ocean. In Japan, researchers have started using seafloor acoustic instruments to track slow deformation over extended periods, and similar initiatives are being considered in places like Chile and the Pacific Northwest. A newly launched satellite may eventually help fill measurement gaps in regions lacking GPS coverage.
The study also underscores significant shortfalls in global earthquake monitoring, especially in parts of the Pacific where sparse data hinder tsunami risk assessments. The researchers stressed that improved location forecasting should support, not replace, public readiness. Funning said that people's sense of security shouldn't rely on the belief that scientists can predict the exact earthquake, especially in Southern California, where it remains a question of when, not if, a major quake will occur, making preparedness essential.
The team believes their algorithm could ultimately assist scientists in assessing seismic hazards across many of the planet's most active plate boundaries, assuming enough data becomes available. Periollat said that while the timing of major earthquakes remains uncertain, identifying where they are likely to occur is possible, and with better observation and ongoing monitoring, understanding of the world's most hazardous faults will continue to improve.