If a large earthquake were to rattle Tennessee then Nashville and the rest of Middle Tennessee likely would not feel the same damage as other parts of the state, according to a Memphis geologist.
The effects of such an earthquake on Tennessee’s bridges, including one on I-40 that goes over the Tennessee River west of Nashville, is unclear, said Gary Patterson of the Center for Earthquake Research and Information.
“We don’t have a record of a large damaging earthquake in east or Middle Tennessee, but we do in Northwest Tennessee,” Patterson told The Tennessee Star.
A large earthquake that originated in Caruthersville, Mo. in 1895 disrupted Nashville, to an extent, by damaging chimneys and cracking walls, Patterson said.
“That is the only record I’ve seen of quake damage in Nashville, although the larger earthquakes of 1811 and 1812 certainly affected the city,” Patterson said.
Tennessee lies along two fault lines — — the New Madrid Fault Line in West Tennessee and the East Tennessee fault line.
As The Star reported, a series of high-magnitude quakes that originated in the central part of the United States wrecked Memphis in 1811 and 1812. Those quakes started along the New Madrid Fault line in Missouri. Their reverberations rattled church bells as far away as Boston, Mass.
“The primary risk for Nashville is large earthquakes at considerable distance, not moderate earthquakes underneath the town,” Patterson said.
As for the I-40 bridge near Sugar Tree in Decatur County — or any other bridge in Tennessee — Patterson said real damage doesn’t set in until you have a magnitude 6 or 6.5 earthquake on the Richter Scale.
“Any bridge that is older may not reflect current-sized standards. That does not mean it is not up to snuff” Patterson said.
“With bridges from the 1900s to the 1940s, engineers (at the time) admitted they didn’t know all the forces they were building for, so they overbuilt quite often. Later we thought we knew what the design specifications would be. Earthquakes showed us we may have underestimated some.”
As reported, a large-magnitude earthquake in the central part of the United States would jolt Tennessee and do far more damage here than another similar-sized quake out west could do to California, Patterson said.
That’s because Tennessee and California have different type terrains, and that makes all the difference, Patterson said.
Also, as reported, officials with the Tennessee Emergency Management Agency say they’ve spent decades planning for a large earthquake and say it’s best for other Tennesseans to do the same.
TEMA spokesman Dean Flener told The Star that members of his agency train for such a quake and have emergency plans to mobilize resources and list which federal government or state resources they have at their disposal
They also have a plan to check roads, bridges, and interstates, Flener said.
A large-magnitude earthquake in the central part of the United States would jolt Tennessee and do far more damage here than another similar-sized quake out west could do to California, Patterson said.
That’s because Tennessee and California have different type terrains and that makes all the difference, he added.
Earthquakes can cause damage not covered under your homeowners, renters or condominium insurance policy — not unless you’ve added an endorsement to your policy, said Tennessee Department of Commerce and Insurance spokesman Kevin Walters.
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Chris Butler is an investigative journalist at The Tennessee Star. Follow Chris on Facebook. Email tips to [email protected].