Mine collapse, Mag 3.1, in Tennessee

[Astronuc]

I was looking at US Earthquake Activity during the past 30 days, and noticed

M 3.1 Mine Collapse - 4 km SSW of Crab Orchard, Tennessee ​

https://earthquake.usgs.gov/earthquakes/eventpage/se60353147/executive

• 2021-08-13 11:57:17 (UTC)
• 35.877°N 84.898°W
• 0.0 km depth

One often sees quarry blasts, but they typically less then Mag 2, or in the range of Mag 1 to 2.

 

[Baluncore]

It was an extensive underground limestone mine.
“The internal collapse of the mine, now owned by Lhoist North America and is approximately two miles deep into the mountain with three levels, occurred around 6:30 this (Friday) morning. There were workers at the mine but none suffered injuries according to sources.”
http://crossvillenews1st.com/report...stone-mine-crab-orchard-lhoist-north-america/