Looking at the light pollution map [1]. There is a band of light between San Antonio and Corpus Christi that does not follow the cities/roads where you would except to see light.
I saw the same thing. I've looked at the "earth lights" pictures for years, and you can pick out cities and the basic highway grid ... so those cloudy patches in North Dakota and southwestern Texas stand out.
He he, those cloudy patches are what keeps OPEC up at night.
Ah yes you are right. I had figured this was the case but was not sure. You can look at this map of the Eagle Ford Shale and it matches up almost perfectly.
Anyone know what this band represents?
[1] http://www.youcanseethemilkyway.com/light-pollution/