KDOT Conducts Seismic Survey on U.S. Route 69 Through Treece, KS

KDOT Conducts Seismic Survey on U.S. Route 69 Through Treece, KS
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KDOT is doing its due diligence, making sure the old Webber Barr mines running underneath U.S. Route 69 aren’t at risk of collapsing underneath the road.

“If we saw an area with the seismic survey that had a collapsed area that was migrating towards the surface then we would have to make a decision of whether we want to close the road or whatever it may be at that point,” says KDOT Chief Geologist Bob Henthorne.

Wires and devices called geo-phones line the highway through Treece for about a mile and a half to the state line, sending sound waves through the ground to create a 3D model of the mine below

“We’re sending waves clear down to the top of the basement rock, Precambrian rock, that’ll get reflected off that and come back up and so we’ll be able to monitor how deep that is through here. We’re also going to go up through the Mississippian trough which is just to the north of us with that same survey.”

This Vibroseis machine is what’s doing all of the work. It’s sending about 20-250 Hz below ground about 2000ft at 12 second intervals to measure the properties of the rock below and the condition of the mines.

“It’s like a sewing machine when you start it up and it speeds up faster and faster, and what that does is that takes the sound that you and I hear and it spreads it out,” says Nick Miller of the Kansas Geological Survey at the University of Kansas.

Preliminary results won’t be in till Christmas but officials say they aren’t expecting to find anything out of the ordinary.

Miller says “Right now, we’re just trying to see…rather than try to do a needle in a haystack, which is to drill down and see what’s going on, we’re trying to get an image of it so we can get some idea where might be a good spot to drill if there’s even a need to. And we got nothing that says that there is but, just on the off chance that we see something funny or unusual, we have a target to look for.”