A rare seafloor earthquake occurred in the Gulf of Mexico about 130 miles southeast of Gulfport, Mississippi, and the source can’t be easily explained, experts say.
The 3.3-magnitude quake happened around 11:15 p.m. Sunday, June 4, along the continental shelf, U.S. Geological Survey data shows.
That area has no known fault lines or tectonic plate boundaries. But there could be an unknown fault line in the spot, according to USGS geophysicist Amy Vaughan.
“It’s weird, but not too weird,” Vaughan told McClatchy News. “It’s just a rare thing and it goes to show it can happen anywhere. Things shift and move all the time and fault zones can exist anywhere. It is less common in that area, but we do have some history of them there.”
The closest town to the quake is Venice, Louisiana, about 95 miles northeast, and no one there reported feeling it.
USGS data shows it was centered just over 3 miles below the seafloor, the USGS says. At 3.3 magnitude, it likely would not have caused fracturing of the seafloor and was not strong enough to generate tsunami activity, experts say.
The odd earthquake is similar to a 4.5-magnitude quake that occurred in April along the East Coast, about 325 miles southeast of Buxton, North Carolina.
The quake was centered 6 miles below the seafloor and not near any known fault zone, undersea volcano, seafloor vents or anything else known to prompt quakes.
It was strong enough to generate reports of people feeling weak shaking in five East Coast states, McClatchy News reported.