CLOSE Geologist, Dr. Bob Hatcher explains the frequency of regional earthquakes and how they differ from those along West Coast faultlines. 
 
 A screenshot of a USGS map showing the reach of a 4.4 magnitude earthquake rattling Tennessee and Georgia. (Photo: U.S. Geological Survey) 
 
 Residents in Tennessee and Georgia got a big surprise Wednesday morning: the rumblings of an earthquake. 
 
 A magnitude 4.4 earthquake was recorded by the U.S. Geological Survey at around 4:14 a.m. ET, with its epicenter near Decatur, Tenn., which is roughly more than 150 miles from Nashville. It's the strongest earthquake to strike Tennessee in 45 years. 
 
 An aftershock was felt about 13 minutes later with a magnitude of 3.3, said the USGS. 
 
 According to Atlanta TV station WXIA, the earthquake was felt as far as northern Georgia. 
 
 Some light and weak shaking was felt as far as Nashville and Murfreesboro to the west and even north into Kentucky. 
 
 According to the USGS, the Eastern Tennessee seismic zone is one of the most active earthquake areas in the Southeast. The zone extends across Tennessee and northwestern Georgia into northeastern Alabama. 
 
 Confused residents in the region took to social media, including Twitter, to confirm the earthquake. The hashtag #earthquake is among the top trending searches on Twitter as of Wednesday morning. 
 
 There have been no reports of serious damage or injuries. 
 
 I'm so glad Twitter exists so I could confirm that we just had an earthquake and it wasn't me just losing my mind here in suburban Atlanta #earthquake — Rachel Rothstein (@rachroth1229) December 12, 2018 
 
 I’m so thankful for twitter so I don’t have to feel crazy and I can confirm other people indeed felt an #earthquake — Amber Lynn (@alyttlewriting) December 12, 2018 
 
 The National Weather Service in Morristown, Tenn., reported on Twitter the quake was the second strongest on record in East Tennessee. The strongest was a 4.7 magnitude earthquake that struck the region in 1973. 
 
 This morning's M4.4 earthquake near Decatur is the second strongest on record in East TN, according to the USGS. The strongest was a M4.7 near Maryville in 1973. #earthquake — NWS Morristown (@NWSMorristown) December 12, 2018 
 
 John Paul, a TV anchor with local station WSOC, reported the quake happened across the river from the Watts Bar Nuclear Plant in Tennessee. In a statement, the Tennessee Valley Authority said their facilities including the plant were not impacted by the earthquake. 
 
 TVA facilities are designed to withstand seismic events & were not impacted by Wednesday morning’s earthquake. They continue to safely operate. Personnel are currently conducting further inspections as a precaution. Our top priority remains the safety of the public. — Tennessee Valley Authority (@TVAnews) December 12, 2018 
 
 Contributing: Kelli Krebs, The Tennessean 
 
 Follow Brett Molina on Twitter: @brettmolina23. 
 
 Read or Share this story: https://www.usatoday.com/story/news/nation/2018/12/12/earthquake-magnitude-4-4-hits-tennessee-georgia/2286910002/ ||||| COLUMBIA, S.C. (AP) — The snow and ice dumped by an unusually severe winter storm were melting, once-frigid temperatures were rising and residents of South Carolina and Georgia finally had begun to relax. 
 
 Then the earth shuddered. 
 
 A small earthquake shook both states late Friday, shaking homes and rattling residents hundreds of miles away. 
 
 The quake happened at 10:23 p.m. and had a preliminary magnitude of 4.1, according to the U.S. Geological Survey's website. It was centered 7 miles west of the town of Edgefield, S.C. , and was felt as far west as Atlanta and as far north as Hickory, N.C., each about 150 miles away. 
 
 "It's a large quake for that area," said USGS geophysicist Dale Grant. "It was felt all over the place." 
 
 The U.S. Army Corps of Engineers reported two nearby dams on the Savannah River appeared to be undamaged, but planned a thorough inspection Saturday morning, Edgefield County Emergency Preparedness Director Mike Casey said. 
 
 Casey said the quake was centered in a sparsely populated part of Edgefield County where there are a lot more rabbits and deer than people. He was driving around and hadn't found any damage, but he expects some reports of minor damages to come in once the sun rises. 
 
 "To get an accurate assessment we're going to need daylight. I could be looking at damage in the dark and not know it. Tomorrow morning, I go out to get my paper and I see the bricks in my house are cracked," Casey said. 
 
 Authorities across South Carolina said their 911 centers were inundated with calls of people reporting what they thought were explosions or plane crashes as the quake's low rumble spread across the state. 
 
 Reports surfaced on Twitter of a leaking water tower in Augusta, Ga., following the quake, but the tower was damaged by ice from a winter storm earlier this week and not the quake, said Richmond County Sheriff's Lt. Tangela McCorkle. 
 
 No damages or injuries from the quake itself had been reported, said South Carolina Emergency Management Division spokesman Derrec Becker. The ice storm felled a lot of trees in the area, which could make it more difficult to determine what damage was caused by the quake. 
 
 South Carolina Gov. Nikki Haley felt the earthquake at the governor's mansion in Columbia. She asked the Department of Transportation to inspect bridges in the area Saturday morning as a precaution, said her spokesman Doug Mayer. 
 
 Tom Clements, a resident of suburban Columbia about 60 miles east of the quake's epicenter, said he felt the walls of his brick house shaking "and they were definitely shaking like what I've experienced before in Latin America" during an earthquake. 
 
 Clements said he immediately went outside to see if anyone else had felt it and he found two neighbors who had. 
 
 "One thought a tree had fallen" under the weight of ice dumped by the storm, he said. 
 
 Earthquakes aren't unheard of in the region. A 4.3-magnitude earthquake happened in Georgia in August 1974 several miles west of Friday's quake. Three others of similar magnitude have been felt in South Carolina in the past 40 years, according to the USGS. 
 
 The largest earthquake ever recorded on the East Coast was a 7.3-magnitude quake near Charleston in August 1886 that killed at least 60 people. 
 
 ____ 
 
 Adams reported from Atlanta.
– "I'm so glad Twitter exists so I could confirm that we just had an earthquake and it wasn't me just losing my mind here in suburban Atlanta," reads a sample Wednesday tweet, one of many that helped make #earthquake a trending topic. Residents of Tennessee and Georgia took to social media to express their shock shortly after 4:14am EST when the US Geological Survey recorded a 4.4-magnitude earthquake originating near Decatur, Tenn., followed by a 3.3-magnitude aftershock 13 minutes later, per USA Today. Shallow at 5.5 miles below the surface, the quake was the strongest to hit eastern Tennessee in 45 years, per the New York Times. (A 4.7-magnitude earthquake struck the region in 1973.) Weak to moderate shaking was not only felt 150 miles away in Atlanta, Ga., but also in Kentucky, North Carolina, South Carolina, and Alabama, according to USGS. There have been no reports of injuries or serious damage, including at one of the nation's largest nuclear power stations. Watts Bar Nuclear Plant, two miles east of the quake epicenter, is "designed to withstand seismic events," says the Tennessee Valley Authority.