Earthquakes shake SC on Monday. Here’s how it compares to our recent quakes

An early-afternoon earthquake in South Carolina was confirmed by the U.S. Geological Survey Monday.

Then, about 5 1/2 hours later, a second one was confirmed.

The twin quakes continued a recent trend of seismic activity in the state’s Lowcountry, where three earthquakes were reported over five days in July. Two other low-magnitude quakes were recorded in that area in August.

Monday’s initial 2.46-magnitude earthquake happened at 12:49 p.m. near Ridgeville, according to the South Carolina Emergency Management Division. The second earthquake, which took place at 6:21 p.m. in Summerville, was slightly stronger than the first, with the USGS reporting it had a 3.3-magnitude.

The site of second quake also took place in an area just a few miles away from Ladson, where the three quakes were recorded near the Dorchester, Charleston, and Berkeley counties border in July.

As of 1:45 p.m., more than 150 people reported feeling Monday afternoon’s quake, according to the U.S. Geological Survey.

The first earthquake was recorded at a depth of 6 kilometers (about 3.7 miles), according to the USGS.

The second earthquake was recorded at a depth of 5 kilometers (about 3.1 miles), according to the USGS.

The July quakes in Ladson measured at 1.3 magnitude and 3.5 kilometers, 1.09 magnitude and 3.8 kilometers, and 1.95 magnitude and 3.97 kilometers.

Two earthquakes were confirmed in Centerville on Aug. 21 (1.75 magnitude and 1.97 kilometers) and Aug. 26 (1.71 magnitude and 3.37 kilometers), according to the USGS.

No damage or injuries have been reported from Monday’s quake.

It’s possible most people did not feel the earthquake, as the ones that register 2.5 magnitude or less often go unnoticed and are only recorded 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.

Anyone who did feel the quake can report it to the USGS.

This was the 11th earthquake in South Carolina in 2021 confirmed by the USGS, with seven recorded in the Lowcountry. The first was a 2.1 magnitude quake reported near Dalzell on Jan. 18. It happened about 40 miles east of Columbia at about 6 a.m. and had a depth of 6.9 kilometers, according to the USGS.

A Lowcountry quake was reported on Feb. 13, when a 2.1 magnitude earthquake was recorded near Summerville, according to the USGS.

On May 12, a 1.8 magnitude earthquake was confirmed near Heath Springs, the USGS said.

Two earthquakes were recorded near Lexington County on May 31, when a 2.0 magnitude earthquake followed one that registered at 2.6 magnitude, the USGS reported.

Dating back to July 2020, there have been at least 17 earthquakes in the Palmetto State, according to the South Carolina Department of Natural Resources.

It is typical for South Carolina to have between six and 10 earthquakes a year, the S.C. Geological Survey reported. There were at least 11 earthquakes reported by the USGS in South Carolina in 2020.

One of the most powerful earthquakes recorded in South Carolina happened in Charleston on Aug. 31, 1886. The estimated 7.3 magnitude quake killed 60 people and was felt over 2.5 million square miles, from Cuba to New York, and Bermuda to the Mississippi River, according to the Emergency Management Division.

The State reporter Caitlin Byrd contributed to this report from Charleston.