Pair of earthquakes strikes Venezuela 39 seconds apart

Two earthquakes struck Venezuela on Wednesday with onsets separated by 39 seconds. The U.S. Geological Survey classified the events as a doublet sequence, recording magnitudes of 7.1 and 7.5 in the same area. The rapid succession of shaking likely contributed to additional building collapses. At least 188 people were killed, 1,520 were injured, and more than 150 remain missing.

Fault system and plate movement The earthquakes occurred along a complex fault zone near San Felipe where the South American and Caribbean plates slide past each other. The Caribbean plate moves eastward relative to the South American plate at about 20 millimeters per year.

Initial data indicate both events were strike-slip ruptures. Researchers said the tangled network of faults will require further study to determine exactly which segments broke.

Historical context and research value Venezuela has recorded five magnitude-7 or larger earthquakes since 1900, but none along the same fault zone as Wednesday’s events. The area had likely been accumulating stress for more than two centuries. Scientists noted that doublet sequences occur in roughly 22 percent of magnitude-7.5 and larger earthquakes worldwide.

The new data will help map how stress transfers between faults in the region.