The Niobrara oil and gas play is an Upper Cretaceous formation in the Rocky Mountain region. The deep formation underlying northern Colorado, western Nebraska and eastern Wyoming is where the oil rush is taking hold.

Highly productive wells are being tapped in Colorado, just south of the Wyoming line. Horizontal drilling and other newer drilling technologies are being applied to the Niobrara formation, which is geologically similar to North Dakota’s Bakken play.

The self-sourced hydrocarbon system has organic carbon content in the 1% to7% range and is produced at depths ...