DAYTONA BEACH, Fla. — A 3.7 magnitude earthquake detected about 168 nautical miles northeast of Daytona Beach Shores has been reclassified and is now thought to have been caused by a man-made explosion.
New information from the U.S. Navy was what prompted the U.S. Geological Survey to change its designation of the quake.
The incident is now called an “experimental explosion,” according to the USGS.
Reported at 4 p.m. Saturday, the “earthquake” was detected about 3 miles below the surface of the ocean and was not strong enough to be felt on land.
At about the time the quake was detected, the Navy confirmed Tuesday that it was conducting a full-ship shock trial on the USS Jackson.
In the trials, explosives are put underwater to test how well ships and their equipment can hold up in the event they end up close to a blast.
A USGS spokesperson said that once their equipment registered what seemed to be a 3.7 magnitude earthquake, the issued the notifications within 20 minutes.
He said they weren’t told ahead of time that any naval testing would be going on in the area, so they could only go odd the seismic readings.
They later updated their alert to say experimental testing.
The Navy notified the National Oceanic and Atmospheric Administration’s National Marine Fisheries Service that another shock trial would be conducted between July 16 and July 20.
The Associated Press contributed to this story.
Cox Media Group
