News of a rare South Carolina earthquake burned up social media among residents in York, Chester and Lancaster counties Friday night and Saturday, but emergency officials say no damage was reported locally.
The 4.1-magnitude earthquake, centered outside Edgefield near the South Carolina-Georgia state line, sent tremors hundreds of miles in all directions and shaking the three counties late Friday night. Many local residents called 911 when the earthquake hit at 10:23 p.m.
Some told emergency operators they heard an explosion. Others recognized the activity as an earthquake, said Cotton Howell, York County’s emergency management director.
The Catawba Nuclear Station on Lake Wylie and the Lake Wylie dam and hydroelectric station – both operated by Duke Energy – have sophisticated seismic activity detectors that require very little seismic activity to trip alarms, Howell said.
Friday’s quake did not register on those seismic readers. Had the quake been bigger, Howell said, it would have triggered alarms and sent officials into “full emergency mode.”
Readers of The Herald reported on social media that they felt the quake in Lesslie, Lake Wylie, Catawba, Rock Hill, York, McConnells, Fort Mill, Tega Cay, Chester and Lancaster.
One woman wrote that her “cabin shook, roof shook, floor rumbled.” A Lancaster County woman said her entertainment center was moved and the glass table in her living room shook so hard it nearly broke.
Melba Carter, who lives in the western Chester County community of Baton Rouge, said her entire house shook as she heard a rumbling noise outside, causing her and others in her home to jump into action.
“We looked at each other and went to the door, thinking it was an accident outside,” she said. “I jumped right on the phone and Facebook. Everybody I was calling felt it, too.
“Then I felt better. I didn’t want to think I was going crazy.”
From an emergency management perspective, the small quake was not significant, Cotton said, but it did give people something to talk about.
The tremors felt in many parts of the three counties are nothing compared to what South Carolina residents felt in 1886 when a “significant” 7.3-magnitude earthquake shook Charleston, Howell said. Then, “we had church bells ringing and chimneys fall in Rock Hill.”
The area felt another “historic earthquake” in 1913, he said, when a quake rattled Union County and the surrounding area.
The quake was centered on the edge of Thurmond Lake seven miles west of Edgefield, just north of one of the areas hardest hit during last week’s snow and ice storm.
Checking, just in case
Inspectors on Saturday found no damage to the state’s major bridges, overpasses, hydroelectric dams and nuclear power plants. Government agencies and utilities spent much of the day checking for earthquake-related problems.
“No injuries, no reports of damage,” said Derrec Becker, spokesman for the state Emergency Management Division. “The only lingering threat is that South Carolina is an earthquake-prone state and these things cannot be predicted.”
Becker said emergency officials had received no reports of aftershocks Saturday.
The earthquake was larger than any in South Carolina since a 4.4-rated quake hit the Charleston area in 2002 and the second-most intense since 1950. The biggest recorded in state history was the 1886 quake.
People across much of South Carolina reported feeling the quake, which some said shook their homes for 5 seconds or more. Residents as far away as Hickory, N.C., and Atlanta also reported feeling the shock.
The S.C. DOT reported Saturday evening that its inspectors had found no problems at bridges near the epicenter and at nearby lakes and rivers. The I-20 Savannah River bridges are owned and maintained by Georgia’s DOT. South Carolina and Georgia officials are coordinating their responses, S.C. authorities said.
Inspectors also checked nuclear power plants in Oconee, York and Fairfield counties, as well as the Savannah River Site nuclear weapons complex near Aiken, but found no damage, spokespeople for Duke Energy, SCE&G and the U.S. Department of Energy said. Major dams also fared well, authorities said.
SCE&G, Duke and Energy Department officials said their equipment did not register earthquake levels high enough to trigger further action, but they chose to check facilities anyway.
“I wouldn’t say there was concern,” SCE&G spokesman Eric Boomhower said late Saturday afternoon. “Any time you have a seismic event, we always are going to go out and take a look at our facilities to see if possibly something was compromised.”
‘Pretty good sized’
Earthquakes are more common than people may realize in South Carolina, but most aren’t large enough for many people to notice.
Geologists said the quake happened three miles underneath the earth’s surface.
Lowcountry residents felt the quake more acutely than did people who live near a monitoring station in Campobello, near Spartanburg, according to scientists in the South Carolina Earthquake Education and Preparedness program at the College of Charleston’s Department of Geology and Environmental Geosciences. The hard-rock soil of the Upstate rumbles less than the sandy areas along the coast.
That’s also why earthquakes, even of a low magnitude, do more damage along the coast, the scientists said Saturday.
Overall, eastern earthquakes are felt over larger areas than those on the West Coast, said Pradeep Talwani, a retired University of South Carolina earthquake expert. Fewer faults in the east allow eastern quakes to be felt more broadly, he said.
“The Charleston earthquake of 1886 was felt over 2 million square miles,” Talwani said. “It rang bells in Boston, it was felt in Chicago, it was felt in Texas, it was felt in Bermuda. A comparable earthquake, the World Series earthquake (of 1989), was barely felt outside of California.”
Quakes of 4.1 can cause cracks in walls or force items off of shelves, he said, but they would not normally cause buildings to fall down.
Eric Strom, director of the U.S. Geological Survey’s water science office in Columbia, said the quake “was pretty good sized” for this part of the country.
In a 10-minute period, a geological survey website registered about 2,000 comments in which people said they had felt the shaking, said Jim Landmeyer, who works with Strom in the USGS Columbia office.
The State newspaper and The Associated Press contributed to this report