Post by JoannaL on Jan 5, 2022 15:57:03 GMT -5
South Carolina Earthquakes Baffle Experts
Another earthquake has rattled Columbia, South Carolina’s capital city, the 9th in a series that have geologists puzzled.
According to the U.S. Geological Survey, a 2.6-magnitude earthquake struck near Elgin, about 25 miles northeast of Columbia, early this morning. The community of less than 2,000 residents near the border of Richland and Kershaw counties has become the epicenter of a spate of recent seismic activity, beginning with a 3.3-magnitude earthquake on Dec. 27. The quake shook glass windows and doors in their frames, sounding something like a heavy piece of construction equipment or concrete truck rumbling past.
Since then, eight additional earthquakes have been recorded nearby, ranging in magnitude from 1.7 to 2.6.
The South Carolina Emergency Management Division says the state typically averages up to 20 quakes each year and clusters aren’t unusual. Last year, six small earthquakes rattled Jenkinsville, approximately 38 miles west of the most recent group of tremors.
Earthquakes are nothing new to South Carolina, although most occur in closer proximity to the coast – Columbia is in excess of 100 miles inland. According to emergency management officials, around 70 percent of South Carolina earthquakes are located in the Middleton Place-Summerville Seismic Zone, around 12.4 miles northwest of Charleston, where, in 1886, the largest recorded earthquake in the history of the southeastern United States occurred. The quake, which is believed to have been of a magnitude of at least 7, killed dozens of people and destroyed hundreds of buildings.The event was preceded by a series of smaller tremors over several days, although at the time, it was not known that the foreshocks were necessarily leading up to something more catastrophic. Unfortunately, there’s no way to know if smaller quakes foreshadow a much more serious event. “You can’t see it coming,” said Steven Jaume, a College of Charleston geology professor. “There isn’t anything obvious moving or changing that you can put your finger on that you can say, ‘This is leading to this.’”
Typically, Jaume continued, the recent quakes near Elgin – which lies along a large fault system extending from Georgia through the Carolinas and into Virginia – would be characterized as aftershocks of the Dec. 27 event, because the subsequent quakes have all been smaller than the first. Nonetheless, he admitted the fact the events keep popping up more than a week after the initial one has caused consternation among the experts who study these events. “They’re not dying away the way we would expect them to,” he added. “What does that mean? I don’t know.”
Sources: The Associated Press and Fox News, January 5, 2022.