MYRTLE BEACH, SC (WMBF) – Several viewers reported hearing a loud boom and feeling their house shake at about 2:30 p.m. Saturday afternoon.
There has been no reported earthquake activity in the area, said Don Blakeman, a geophysicist with the National Earthquake Information Center.
Blakeman couldn't say for sure, but guessed it could a sonic boom. He said that in the past, after investigating activity in this part of the country, they found out later it was a sonic boom, which is the sound associated with the shockwaves caused by a supersonic aircraft breaking the sound barrier.
He said they "very rarely get any verification if military was involved."
Viewers reported hearing and feeling the boom around the area, including in Carolina Forest, Socastee, Forestbrook, Loris, and Myrtle Beach.
Back in December, viewers reported a similar loud, shaking "boom" on a Thursday afternoon. While there was no definitive answer at the time, the US Geologic Survey offered some other possible explanations:
Earthquake "booms" have been reported for a long time, and they tend to occur more in the Northeastern US and along the East Coast. Of course, most "booms" that people hear or experience are actually some type of cultural noise, such as some type of explosion, a large vehicle going by, or sometimes a sonic boom, but there have been many reports of "booms" that cannot be explained by man-made sources. No one knows for sure, but scientists speculate that these "booms" are probably small shallow earthquakes that are too small to be recorded, but large enough to be felt by people nearby.
And another possible explanation:
The term "Seneca guns" is just a name, not an explanation. It does not tell us anything about what causes these noises and shakings. The name originated in a short story that James Fennimore Cooper wrote during the 1800's. The name refers to booms that have been heard on the shores of Lake Seneca and Lake Cayuga in New York State. The name has been applied to similar noises along the coasts of North Carolina, South Carolina, and Virginia. Similar booms are called Barisol guns in coastal India. These phenomena have also occurred in three widely separated places around the world. That's about all we know about the Seneca guns.
You can read more about "booms" and how often they have been reported in this area on the USGS website.