UC Riverside Scientists Identify Major Earthquake Hotspots

Scientists at the University of California-Riverside have developed a novel methodology that can identify with greater accuracy where major earthquakes are likely to occur along tectonic faults. The research, led by geophysicists Gareth Funning and Axel Periollat, focuses on measuring accumulated strain in subduction zones, which are areas where one tectonic plate slides beneath another and are the sites of the most powerful seismic events, including magnitude 8.5 quakes and tsunamis.

The new technique does not predict the timing of an earthquake, but rather pinpoints the specific geographic locations where stress has built up to critical levels. Tectonic faults accumulate strain over many years, and this process can now be measured by observing subtle ground movements using GPS data. The algorithm developed by the UCR team identifies locked portions of faults, known as asperities, which resist movement until sufficient stress triggers a large rupture.

Identifying Strain Accumulation in Subduction Zones

A key test of the methodology involved the 8.8-magnitude megathrust earthquake that struck the Kamchatka Peninsula in eastern Russia in July 2025, an event that prompted a tsunami warning for the western United States. The UCR model successfully highlighted the exact section of the Kamchatka subduction zone where this massive earthquake later occurred. Researchers noted that while the timing of the event was beyond the scope of their method, the rupture took place precisely in the area their model indicated strain had accumulated.

This finding offers a significant advancement in understanding earthquake dynamics. Previously, scientists could broadly identify areas prone to large quakes, but pinpointing the exact section of a fault most likely to rupture has remained a challenge. The UCR research suggests that by measuring the subtle deformation of the Earth's crust, scientists can identify these high-risk 'hotspots' with unprecedented precision.

The study also provided insights into the 2025 Kamchatka earthquake compared to a 1952 event in the same region. The researchers found that the 2025 quake, though powerful, generated a smaller tsunami, suggesting that the shallowest part of the fault slipped less than it did in the 1952 event. This level of detail, derived from analyzing the rupture's characteristics in relation to the measured strain, further validates the UCR team's approach.

According to a statement from the university, geophysicist Axel Periollat commented on the findings, saying, "We had an idea where the strain was accumulating based on a relatively limited data set. Seeing it work so well confirmed that this approach has real potential." The research team intends to apply their method to other critical subduction zones along the Pacific Ocean's Ring of Fire, a region known for its high seismic activity.

While this technology cannot forecast *when* an earthquake will strike or the exact size of a potential tsunami, its ability to narrow down the locations of greatest seismic hazard could significantly improve long-term disaster planning and public preparedness efforts. Understanding where stress is most concentrated allows authorities to focus resources and implement more targeted mitigation strategies.