Richland County hit by South Carolina’s first earthquake of 2023

It’s not surprising that the Midlands were the site of South Carolina’s first confirmed earthquake of 2023. But it is unique that the earthquake hit in Richland County.

A 1.9 magnitude earthquake was confirmed in the Hopkins area at 11:03 p.m. Tuesday, the South Carolina Emergency Management Division said.

The earthquake happened at about 3.7 miles beneath the surface, according to the U.S. Geological Survey.

This was the first seismic activity in South Carolina since a 1.7 magnitude quake was recorded in the Elgin area on Dec. 9, according to the state Department of Natural Resources.

There has been recent seismic activity in neighboring states North Carolina and Georgia. A 1.24 magnitude quake was reported in North Carolina earlier Tuesday and a 2.34 quake was confirmed in Georgia on Jan. 3, according to the USGS.

While it has been uncommon for earthquakes to hit in Richland County, there have been 45 confirmed earthquakes in Kershaw County since the end of June, according to the South Carolina DNR.

That’s also where South Carolina’s most powerful recent earthquakes were recorded on June 29. On that day, two earthquakes — one a 3.5 magnitude and the other 3.6 — were included in a flurry of tremors and aftershocks. Those were the two largest quakes to hit South Carolina in nearly a decade. A 4.1-magnitude quake struck McCormick County in 2014.

Anyone who felt tremors and shaking or heard rumbling from Tuesday night’s earthquake can report it to the USGS.

The most recent earthquake means at least 77 have been detected in the Palmetto State since the start of 2022, according to South Carolina DNR. All but seven of the quakes have been in the Midlands.

In all, 77 earthquakes have hit the Columbia area since a 3.3-magnitude quake was recorded Dec. 27, 2021, according to the DNR.

The S.C. Emergency Management Division said Tuesday’s earthquake was classified as a micro quake, according to the Modified Mercalli Intensity Scale.

No major damage or injuries have been reported from any of the recent quakes.

Earthquakes that register 2.5 magnitude or less often go unnoticed and are usually recorded only by a seismograph, according to Michigan Technological University. Any quake less than 5.5 magnitude is not likely to cause significant damage, the school said.

It is typical for South Carolina to have between six and 10 earthquakes a year, the S.C. Geological Survey previously reported. There have been 103 earthquakes in South Carolina since Jan. 18, 2021, according to DNR.

During a recent town hall to address the earthquakes, state geologist Scott Howard said as many as 200 smaller tremors might have gone unnoticed and unrecorded.

Why the increase in earthquakes?

An explanation for the recent outburst has eluded scientists.

Some experts have theorized there’s a link between the Wateree River and the earthquakes northeast of Columbia. They said the combination of a single moderate earthquake last December and high water levels in the Wateree River during parts of this year have contributed to the earthquakes. But no one has settled on the single cause for the Midlands’ shaking.

Elgin, located about 20 miles northeast of Columbia and situated on a fault line, has been experiencing an unusual earthquake “swarm” for the past several months, leaving some residents feeling uneasy. The series of quakes might be the longest period of earthquake activity in the state’s history, officials said. But officials have said they don’t believe the spate of minor earthquakes is an indicator that a bigger quake could be on the way.

“Though the frequency of these minor earthquakes may alarm some, we do not expect a significantly damaging earthquake in South Carolina at this time, even though we know our state had them decades ago,” South Carolina EMD Director Kim Stenson previously said in a news release. “Now is the time to review your insurance policies for earthquake coverage, secure any items in your home that may become hazards during a tremor, and remember to Drop, Cover, and Hold on until the shaking passes. These are the precautions South Carolinians can take to properly prepare for earthquakes.”

The strongest earthquake ever recorded in South Carolina — and on the east coast of the United States — was a devastating 7.3 in Charleston in 1886.

That quake killed 60 people and was felt over 2.5 million square miles, from Cuba to New York and from Bermuda to the Mississippi River, according to the state EMD.

Reported earthquakes in SC in 2021-22