A pair of powerful earthquakes struck Venezuela, causing widespread destruction and loss of life, with a magnitude 7.2 earthquake followed just 39 seconds later by a magnitude 7.5 earthquake, about three times more powerful.
The quakes hit close to major population centers, including Caracas, where older buildings are vulnerable to strong shaking, says William Barnhart, a geophysicist at the U.S. Geological Survey. The fact that they struck on land made them especially deadly, with the potential for catastrophic damage amplified by the proximity to densely populated areas.
Venezuela Earthquakes
The earthquakes may have occurred on two separate faults, according to Barnhart, who notes that several faults intersect in this tectonically complex region. Historically, earthquake risk assessments have not accounted for multifault scenarios, says Chris Goldfinger, a paleoseismologist at Oregon State University.
Experts like Goldfinger point to the 2016 Kaikōura earthquake in New Zealand as a similar multifault event that took scientists by surprise and changed their understanding of how interconnected faults can trigger multiple ruptures. Assuming the Venezuelan quakes are similar, it will be crucial information for those studying earthquake risk.
Other places with multiple faults, such as parts of California’s fault system, including the San Andreas Fault, have similarly complex tectonics. A recent study found that parts of the San Andreas and San Jacinto fault systems may now be at their highest modeled stress levels in at least 1,000 years.
Global Implications
Experts say that areas like California are far more prepared for such events than Venezuela, but that level of preparedness is rare. Many buildings around the world were built before plate tectonics was understood, and retrofitting entire cities is a daunting task, says Goldfinger.
The Venezuelan quakes were followed by earthquakes in Japan and California, but these events are unrelated, according to Barnhart. While the coincidence of these earthquakes may seem remarkable, Barnhart notes that earthquakes happen frequently, often without impact.
The broader significance of the Venezuelan earthquakes lies in the need for increased preparedness and understanding of earthquake risk, particularly in regions with complex tectonics, to mitigate the devastating effects of such disasters.
