In the fractured Upper Cretaceous Niobrara play of the central Rocky Mountain region, specific [[Using analogs to identify critical elements|critical elements]] must be present for a prospect to be successful. Since the Niobrara Formation is its own oil [[source rock]], there is no [[Drive mechanisms and recovery#Water drive|bottom water]]; [[Drive mechanisms and recovery#Gas cap drive|gas expansion]] along with [[Drive mechanisms and recovery#Gravity drainage|gravity drainage]] provide the main reservoir energy, so the structural position of a well is not a critical factor. Synclines, anticlines, and any structural location in between will work. The main critical element is to find a sufficiently fractured sweet spot in which the fractures remain open during production. Careful study of numerous excellent Niobrara producing fields shows that the following critical elements must be present to achieve commercial success.
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In the fractured Upper Cretaceous Niobrara play of the central Rocky Mountain region, specific [[Using analogs to identify critical elements|critical elements]] must be present for a prospect to be successful. Since the Niobrara Formation is its own oil [[source rock]], there is no [[Drive mechanisms and recovery#Water drive|bottom water]]; [[Drive mechanisms and recovery#Gas cap drive|gas expansion]] along with [[Drive mechanisms and recovery#Gravity drainage|gravity drainage]] provide the main reservoir energy, so the structural position of a well is not a critical factor. [[Fold trap regime#Classes and definitions|Synclines, anticlines]], and any structural location in between will work. The main critical element is to find a sufficiently fractured sweet spot in which the fractures remain open during production. Careful study of numerous excellent Niobrara producing fields shows that the following critical elements must be present to achieve commercial success.