Tenth Earthquake in 30 Days Strikes South Carolina

The earthquake's epicenter is located at the star inside the colored concentric circles on this map. Image: USGS — The earthquake’s epicenter is located at the star inside the colored concentric circles on this map. Image: USGS

South Carolina has had a rash of seismicity in recent weeks, with earthquakes striking just outside of Charleston near the coast and Columbia in the middle of the state. An earthquake which struck just before midnight last night became the tenth, impacting an area just west of Columbia. There have been three areas getting these earthquakes in recent weeks: the area west of Columbia, like last night’s, an area east of Columbia that has seen a long-term swarm, and an area north and west of Charleston that has seen an uptick in seismic activity lately. South Carolina is home to the U.S. East Coast’s worst recorded earthquake, a catastrophic event which struck Charleston in 1886.

On Sunday night at 11:57 pm, USGS reported a relatively weak magnitude 2.0 earthquake struck near Yacht Cove by Lake Murray outside of the towns of Irmo and Seven Oaks and about 5 miles north and west of downtown Columbia. The earthquake had a depth of 3.6 km. The earthquake was too weak to create any damage or cause any injuries, but a dozen people did report to USGS hearing and/or feeling the earthquake.

According to the South Carolina Emergency Management Division (SCEMD), there are approximately 10-15 earthquakes every year in South Carolina, with most not felt by residents; on average, only 3-5 are felt each year. Most of South Carolina’s earthquakes are located in the Middleton Place-Summerville Seismic Zone. The two most significant historical earthquakes to occur in South Carolina were the 1886 Charleston-Summerville quake and the 1913 Union County quake. The 1886 earthquake in Charleston was the most damaging earthquake to ever occur in the eastern United States; it was also the most destructive earthquake in the U.S. during the 19th century.

The 1886 earthquake damaged these structures on Tradd Street in Charleston, South Carolina. Image: USGS

The 1886 earthquake struck at about 9:50 pm on August 31; it was estimated to have been rated a magnitude 6.9 – 7.3 seismic event. The earthquake was felt as far away as Boston, Massachusetts to the north, Chicago, Illinois and Milwaukee, Wisconsin, to the northwest, and New Orleans, Louisiana to the south. The earthquake energy even traveled as far away as Cuba and Bermuda, where some shaking was felt too. The initial earthquake lasted about 45 seconds.

While the U.S. West Coast is best known for their earthquakes, there is considerable earthquake risk elsewhere in the country. Image: USGS

The 1886 Charleston earthquake was responsible for 60 deaths and over $190 million (in 2023 dollars) in damage. The area of major damage extended out 60-100 miles from the epicenter, with some structural damage even reported in central Alabama, Ohio, eastern Kentucky, southern Virginia, and western West Virginia from the initial quake.

A study published in 2008 in the Journal of Geotechnical and Geoenvironmental Engineering hypothesized that if such an earthquake were to strike the region today, it would lead to approximately 900 deaths, 44,000 injuries, and damages in excess of $20 billion in South Carolina alone.