A pair of powerful earthquakes struck near Caracas in quick succession, producing far worse effects than a single quake would have. William Barnhart, a geophysicist at the U.S. Geological Survey, notes that a magnitude 7.2 alone in this region would be devastating, but it was followed just 39 seconds later by a magnitude 7.5 — roughly three times more energetic. Because both quakes occurred on land and close to densely populated areas with many older, vulnerable buildings, the human toll was especially severe.
Early analyses suggest the two shocks may have ruptured different faults in a tectonically complex area where multiple faults intersect. Barnhart cautions that it’s still too soon to say precisely what happened deep underground, but the likely involvement of more than one fault made the events unusual and particularly destructive.
Chris Goldfinger, a paleoseismologist at Oregon State University, says the disaster highlights a blind spot in how earthquake risk is often evaluated. “We always tend to kind of assume that earthquakes will just be on one fault and only on one fault,” he says. Past surprises, such as the 2016 Kaikōura earthquake in New Zealand, showed how multiple, interconnected faults can rupture in a single multifault event — changing scientists’ expectations about how earthquakes can cascade across complex fault networks.
Those findings matter for other regions with many closely spaced faults, including parts of California’s San Andreas and San Jacinto systems. A recent study has suggested some segments there may now be at the highest modeled stress levels in at least a millennium. But experts point out that California’s infrastructure and emergency systems are generally better prepared for large, complex earthquakes than Venezuela’s.
Goldfinger emphasizes a broader challenge: much of the built environment worldwide was constructed before modern plate tectonics and seismic science informed engineering standards. Retrofitting entire cities is expensive and technically difficult, and in many places engineering has not kept pace with evolving scientific understanding.
The Venezuelan earthquakes occurred the same day as strong, unrelated quakes in Japan and California. Barnhart stresses that those coincidences are not evidence of a connection: earthquakes happen frequently around the globe, and most go unnoticed because they occur offshore or in unpopulated regions. “Most people don’t pay attention because most of the earthquakes are out to sea and nobody is impacted,” he says.
Scientists will continue to study the Venezuelan sequence to determine whether it was a true multifault rupture like Kaikōura, and to refine assessments of seismic hazard in complex fault systems. For now, the event stands as a stark reminder that when large quakes strike close to major population centers — especially in areas with aging buildings and limited seismic preparedness — the consequences can be catastrophic.