A U.S. Geological Survey Community Internet Intensity Map after a 4.4 magnitude earthquake near Decatur, Tenn., early Wednesday, Dec. 12, 2018. (Image courtesy U.S. Geological Survey)
Note: This story was last updated at 4 p.m.
The earthquake near Decatur early Wednesday morning was felt in Oak Ridge, according to social media reports. Oak Ridge Today readers reported feeling the earthquake in other communities such as Clinton, Hardin Valley, Harriman, Oliver Springs, Sevier County, and Atlanta.
The 4.4 magnitude earthquake was also felt in other areas across the Southeast, including in Tennessee, Georgia, and North Carolina.
Some people in the region described it as like a train or truck driving by, and they said homes shook, and doors and windows rattled. Some said it woke them up, and others said they didn’t feel it. (Oak Ridge Today did not feel it.)
The earthquake was reported about nine kilometers underground at 4:14 a.m., according to the U.S. Geological Survey. The epicenter was 11 kilometers north-northeast of Decatur. Oak Ridge is about 45 miles northeast of Decatur.
It was reported to be the largest in Tennessee since a 4.7 magnitude earthquake in Maryville in 1973 and the second strongest on record in East Tennessee. The Maryville earthquake 45 years ago was the strongest in East Tennessee.
There was a second earthquake Wednesday, an aftershock, about 13 minutes after the first and about 6.8 kilometers underground. It was reported at 4:27 a.m., and it was also 11 kilometers north-northeast of Decatur.
There were two other weaker aftershocks as well. One was a 1.3 magnitude at a depth of about five kilometers at 4:59 a.m., 45 minutes after the first earthquake. The second was a 1.4 magnitude about 42 minutes later, at 5:41 a.m., also at five kilometers underground.
There have been a few other less intense earthquakes reported in the region recently, but it wasn’t immediately clear Wednesday morning if the level of activity had changed. In its responses to frequently asked questions, the U.S. Geological Survey said a temporary increase or decrease in seismicity is part of the normal fluctuation of earthquake rates.
“Neither an increase or decrease worldwide is a positive indication that a large earthquake is imminent,” the USGS said.
The ComCat earthquake catalog contains an increasing number of earthquakes in recent years not because there are more earthquakes, but because there are more seismic instruments and they are able to record more earthquakes, the USGS said.
Earthquakes cannot be predicted, and the USGS said neither it nor its scientists have ever predicted a major earthquake.
The Tennessee Valley Authority reported that engineers and site personnel were conducting detailed inspections at all of its facilities in the area including nuclear plants, fossil plants, and dams as a precaution after the earthquakes near Decatur on Wednesday morning.
“All plants continue to operate safely,” TVA said.
The Watts Bar Nuclear Plant is north of Decatur.
“TVA facilities are designed to withstand seismic events and were not impacted by Wednesday morning’s earthquake,” the public utility said. “They continue to safely operate. Personnel are currently conducting further inspections as a precaution. Our top priority remains the safety of the public.”
See the USGS page on Wednesday’s earthquake near Decatur here.
More information will be added as it be becomes available.
The 10 earthquakes closest to Decatur and their intensities are shown going back to Nov. 17, 2018. (Image courtesy U.S. Geological Survey/IRIS)
The U.S. Geological Survey’s 2014 seismic hazard map for Tennessee. (Image courtesy U.S. Geological Survey)
Most news stories on Oak Ridge Today are free, brought to you by Oak Ridge Today with help from our advertisers, contributors, and subscribers. This is a free story. Thank you to our advertisers, contributors, and subscribers. You can see what we cover here.
Do you appreciate this story or our work in general? If so, please consider a monthly subscription to Oak Ridge Today. See our Subscribe page here. Thank you for reading Oak Ridge Today.
Copyright 2018 Oak Ridge Today. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.
