Pipeline Clearings from the Air
Anyone who flies has probably wondered about those very wide, straight lines that cut across the countryside, regardless of terrain, and seemingly unconnected with much of anything. I know I wondered about them for a long time. After thinking about it for a long time, I finally figured it out. They're clearings over pipelines. I should have known that right away, but I didn't really think about it.
We have major pipelines crossing much of the country. As you fly, you'll notice them, if you have a window seat. Straight clearings with varying widths. There's a pipeline under each of those, carrying natural gas, gasoline, crude petroleum or who knows what.
Other clearings that look similar are for high voltage powerlines, but if you look closely, you'll see the towers on those.
One more mystery solved.
= new reply since forum marked as read
I have not flown in so long I have not even thought about that or even remember seeing anything like that from the air. Next time I do fly I will look.
On the ground here there are a lot of natural gas lines and oil lines and some are fairly close to my farm. They are all marked very visibly so it was easy for me to find land that was not too close to them. A bunch of years ago one of them blew up the highway by my farm. *sigh*
Interesting. I know they used to use small planes to check the lines frequently back in the olden days 
. They would be flying low over the farm land quite often and you would see them and know they were either checking lines or crop dusting. I don't see the dusting anymore but I also don't see the flybys checking the lines.
