4.1 earthquake in East TN 5-10-2025

[Machinebuilder]

This was interesting.
At 9:04 AM a 4.1 earthquake hit about 10.5 miles from my house.
the epicenter was just off hwy129 a little east of Foothills Parkway (along Chilhowee lake).
This is pretty much a wilderness area and there is no reported damage.

I was in my shower and heard a rumble and the house shook.

Its probably the strongest earthquake I have felt and the first in a very long time.

[Magicman]

Yes interesting for sure and a sorta long way from the New Madrid area where they had predicted the next quake would be.

I am glad that you are OK.   

[SawyerTed]

Several years ago, 2020, we felt the 5.1 earthquake that hit Sparta, NC.   That's probably 60 miles from here.  I was in bed and it seemed like a prolonged really strong rumble of thunder.  Yes the house shook.  Sparta had damage we didn't.    

[SwampDonkey]

The last quake I felt here was around '82. 5.7 magnitude, but centred in the most remote area of the province. But there have been quakes around this region quite frequently, usually 2-3 mag.

https://earthquaketrack.com/r/new-brunswick-canada/recent

Glad everything is still intact down your way.

[Ianab]

Richter is a scale of the overall size of the quake (total energy released). It's not always the same as how violent the local shaking is. Another scale is MMI, which judges the level of shaking. 

So you can get a deep quake, of Mag 6 or so, that's 50 miles down. Felt over a wide area, but little damage. The Christchurch quakes only measured ~6.x, but were only a mile to 2 below the city. That had the MMI up to 8 or 9. Those would have been a MMI 4 here, but I'm 580ks away. Locally people actually got knocked over or thrown into the air, which is up around MMI 9 or 10. Scale technically goes to 12, but at that level everything flattened. 

We had Aussie visitors at the time, and I think it was their first actual quake. They were a bit freaked out. Locally you judge the shaking, and if it's mild but extended, you assume it's a big quake, but miles away. If it's small and local, it will be sharp, but short. If it's BIG and LOCAL, well everyone in this house knows to dive under one of my computer desks. 

[Machinebuilder]

East TN is not related to the New Madrid fault, its next to the Mississippi River

There is an east Tennessee seismic Zone that sort of follows the Tennesee river valley.

The Source of the seismic activity is unknown.

I see something in the news about small quakes in the area but this is the biggest i have felt.
 the depth was 15.5 mi. I am not finding any MMI info

[SawyerTed]

Our region, Tenn., Georgia, SC, NC and Va, annually have dozens and dozens of earthquakes.  Rarely above a 4.0 on the Richter scale.  Most are below 2 and never felt.  The occasional 5 plus happens and will crack a chimney or topple unsteady stuff in very spotty areas. 


Here's the distribution map.  It shows what Machinebuilder is mentioning. 

[Magicman]

I saw a map last evening that showed another smaller seismic zone North of the New Madrid zone, so Tennessee has 3 zones.  Anyway interesting stuff.

[SwampDonkey]

Years ago before my time a quake hit and it lowered one side of the old rock foundation by 2" in great grandfather's house. I don't think there were any instruments to measure it back then.

[Jim_Rogers]

I was in Long Creek, SC and felt it for sure. At first I thought it was the wind blowing on the building I was sitting in, as I heard the roof noise during the shake. But the owner of the building said it was a quake.

I think it was my first earthquake. My wife said, hopefully my last as well.

Jim Rogers

[Machinebuilder]

I saw a youtube video about it yesterday.

He explained all the geology involved and that the area has a massive amount of ancient faults that are very deep in the bedrock.

I don't know where he got the fault line map as I couldn't find it. it was interesting to see the faults mostly run parallel to the valley.

he also explained some of what you see on the USGS earthquake page.

I'm ok with experiencing an earthquake as long as its not a big one.

[doc henderson]

We have occasional smaller ones here.   vibration and once it made the water in the pool sway from side to side.

[Magicman]

it was interesting to see the faults mostly run parallel to the valley.

I suspect that the valley is there because of the faults.  This crusty old Earth has been going through growing pains for many eons. 

[SawyerTed]

There's a thing called liquefaction where fill soils and other non, compacted soils "liquify" during an earthquake.  That's why certain buildings collapse, the footings fail in the liquified soils.  Others fall due to shaking. 

After the Sparta,NC earthquake, which we felt at our home, our swimming pool floor wrinkled and had waves in it.  The pool liner rests on about 2-3" of sand.  According to my son, the professional civil engineer, the undulations and wrinkles were due to the earthquake. 

The earthquake felt and sounded like a very strong rumble of thunder that lasted 25-30 seconds. 

[SwampDonkey]

You can see the old fault line from eons ago outside of Fredericton. A big vertical cliff in volcanic basalt was created. The slip caused slickensides along the fault. 

https://en.wikipedia.org/wiki/Slickenside