California is bracing for potential seismic activity along the notorious San Andreas Fault, as recent research from the California Institute of Technology highlights the unpredictability of such geological events. A study focusing on the Mw7.7 earthquake in Mandalay, Myanmar, which devastated the region in March 2025, suggests that future ruptures may not conform to established expectations.

The Mandalay earthquake unleashed catastrophic destruction, leading to thousands of fatalities and leaving many more injured or unaccounted for. Tremors were felt across neighboring countries, including China, India, Vietnam, and Thailand. Researchers analyzed satellite images taken before and after the quake to refine existing models that predict the behavior of fault lines.

This earthquake was significant not only for its destructive power but also for the unusual length of the rupture along the Sagaing Fault. Stretching 510 kilometers (about 317 miles), this rupture marked the longest continental rupture recorded. Researchers had anticipated that seismic activity would transpire along a 300-kilometer (approximately 186 miles) segment of the fault due to the longstanding seismic gap.

Contrary to those expectations, the Mandalay quake released more energy than previously thought, indicating that the fault had built up strain over time. This has raised questions about the reliability of current earthquake forecasting models, particularly as they relate to faults like California’s San Andreas.

Both the San Andreas Fault and the Sagaing Fault are straight strike-slip faults, underscoring the importance of reassessing earthquake prediction methodologies. Current seismic hazard models primarily rely on historical earthquake data and do not factor in the evolving state of specific fault segments. This could hinder accurate forecasting for future seismic events.

Researchers argue that many models are time-independent, estimating the chances of an earthquake occurring within a designated timeframe without taking into account the history of fault movement. Effective predictions should be based on when sections of a fault last shifted, which segments experienced slip, and the magnitude of that slip.

Recent findings suggest that future earthquakes may not mirror the characteristics of past events. Jean-Philippe Avouac, an expert in geology and engineering at Caltech, points out that even well-studied faults can behave unexpectedly, releasing more energy than previously recorded during a single event. This insight underlines the inadequacy of historical records, which may not capture the full spectrum of possible earthquake scenarios.

As scientists look to improve forecasting techniques, they are considering physics-based models that could provide a more comprehensive understanding of seismic activity. Such frameworks have the potential to be tailored to real-time observations, offering time-dependent forecasts rather than relying solely on historical patterns.

The implications of this research could reshape how communities prepare for earthquakes, emphasizing the need for updated models that better account for the complexities of fault behavior. The study has been published in the journal Proceedings of the National Academy of Sciences, adding to the discussion on seismic readiness in earthquake-prone regions.