Venezuela ‘doublet’ earthquakes: What to know about back-to-back pair

Venezuela’s pair of earthquakes is considered a doublet sequence. It’s not rare to have two quakes in short succession, but in this case, that most likely led to more destruction.

The second earthquake that hit Venezuela on Wednesday started rumbling before the first had even concluded. Their onsets were separated by just 39 seconds.

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The U.S. Geological Survey has described the pair of earthquakes — a 7.1-magnitude and a 7.5-magnitude — as a doublet sequence, a phenomenon in which two temblors of similar magnitude strike roughly the same area at around the same time.

“The seismic waves from the first one weren’t done yet when the second one happened,” said Harold Tobin, the director of the Pacific Northwest Seismic Network and a professor at the University of Washington.