I was hoping for some sort of volumetric data. I guess that it makes perfect sense that oil and natural gas are found in the same places, however, I never considered it.

I recall reading that the Dakotas have oil reserves that may be as large as the Saudi's, however it looks like that would mean that Texas has far more.

Nevermind, there is a dead geologist that estimated that the Bakken formation in ND had 413B barrels, but current estimates are closer to 2B. The Saudi's have an estimated 267B.

These are two interesting Bakken graphs:

At this rate the Bakken oil should be dry in 5 years. This all makes me think that this map could be very inaccurate.