Text book death by bubble point in Parshall and Sanish, two of the oldest, largest of fields in the Bakken. 
Look what happens to well productivity as GOR goes thru the roof. 

Below, the rate of GOR increase has become almost exponential!!  Now we know why Harold Hamm is becoming a staunch advocate for more pipe out of the Bakken, and more LNG exports from America. Thanks to Enno Peters for this !

Think this will never happen to the Permian Basin Wolfcamp? 

SPC Bakken 10.8.png
Here's another Bakken Oil Field, Grail...death by bubble point.