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That massive rockslide in Polk county has caught the attention of the country.
Seeing the spectacular act of nature has many wondering just why it all came tumbling down.
We went seeking answers.
Vanessa Bateman, TDOT Geologist, "The very first thing that jumped out was the sound."
The popping sound like a car door being slammed...a clear sign of trouble to TDOT geologist Vanessa Bateman.
Bateman, "We couldn't see the rock moving but you could hear it and that's the kind of sound when it makes that, that it's starting to let loose upon the slope."
Sure enough minutes later a wall of rocks, trees, mud and other debris tumbled to the ground...blocking highway 64 in the Ocoee Gorge.
But what caused this awesome show of Mother Nature's power?
Dr. Jonathan Mies, UTC Dept. of Geology, "That rock in the Ocoee is not unlike this rock."
We went to Dr. Jonathan Mies in UTC's geology department for answers.
He says the rocks in the Ocoee have weak spots called cleavage planes.
Dr. Mies, "Particularly when water gets into those planes they are likely to slide and so in looking at that video it appeared that large slabs of rocks slid off of smooth surfaces like this and I would suggest that this is really the reason for that slide."
Dr. Mies discounts the mild earthquakes we see in this area as triggers for this slide.
Dr. Mies, Certainly anytime the ground is agitated you couldn't ignore it as a factor. I don't see it as a real influence here."
Instead he points to recent wet weather as the culprit.
Dr. Mies, "I'd associate this slide probably as much with the rain as anything else and that's quite common for these sorts of rock slides to occur at the time of rain."
An act of nature that put on quite a show.
Bateman, "All of a sudden you hear the rumble and the whole thing came down."
Dr. Mies points out earthquakes are fairly common around here.
We're in the East Tennessee Seismic Zone, one of the most energetic areas in Eastern North America.
They tend to be small with no damage.
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