A couple of days ago, a mysterious spaghetti of orange cable appeared for miles and miles along the side of our road and the River Road. The stakes you can see in the picture were already there -- they first turned up several weeks ago.
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Every so often, the cable was interrupted by a buried sensor of some kind.
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Boxes like this were spaced every quarter-mile or so.
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At the end of Julio's driveway, there were five sensors stuck in the ground close together. Oops, wait, that's seven, at least -- I may have missed some beyond the margins of the photo.
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On Sunday morning, Dad and I noticed a loud, steady, whining kind of roar that filled the air and seemed to be coming from the East. We could hear it all day long. We also saw various white trucks buzzing purposefully up and down our road. Clearly, somebody was working very hard indeed, even though it was Sunday. Finally I put Panda in the car and drove down to the River Road to see what I could see. What I could see was this:
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And this:
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Several guys were directing traffic around the three absolutely enormous trucks. (While I was on the South Cross Road taking this picture, Panda found a deer leg in the pine trees and fell in love.) Each truck had a platform under its belly that could be raised or lowered to be pressed against the ground. This was the source of the roar we could hear a mile away on the farm. Every few minutes, all three trucks would simultaneously raise their platforms, roll forward a short distance, and put the platforms down again. Little by little they worked their way along the full length of the road.
Turns out this is seismic testing, part of the natural-gas prospecting going on right now in Smyrna, Lebanon, and Hamilton. The trucks were sending vibrations through the ground in order to locate areas of natural gas where gas wells might be drilled. I learned from the Internet that the trucks are called "thumpers" or "VibraSeis". It's also possible to find the natural gas by blasting dynamite underground. This will create the necessary vibrations but it apparently can also cause problems with aquifers, water wells, and cracked foundations. We're glad they're doing it this way instead!
The next morning, the trucks made their way down County Road 22. Eventually they showed up at our house. Dad took these pictures.
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He said that when standing near enough to take these pictures, he could feel the vibrations right through the ground. Here's a close-up of one of the trucks showing how it's all put together.
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All three trucks are synchronized -- they put their platforms down together, wait together until some signal (computerized?) tells them that it's time to move on, then pull them up together and roll onward. In this picture, one of the trucks has its platform up a little bit ahead of the other two.
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Here's a close-up of the platform that does the vibrating. It extends across the full width of the truk.
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When they got done at our house, off they went down the road. The cable and sensors stretch all along County Road 22, over the county line into Madison County, and at least a mile farther up the road. If there is natural gas under the ground around here, these guys are going to find it. We hope they find it at our house!