Shales and tight reservoirs within the heterogeneous Bone Spring formation are the new “it” play in the venerable Permian Basin.

The Bone Spring has been producing oil and gas for decades in southeastern New Mexico and West Texas. The Permian-age formation, composed of interbedded sandstones, carbonates and shales, has already enjoyed several cycles of industry attention. Initially, conventional-quality sandstones were targets. Next, high-rate wells were brought in from carbonate lenses, and that phase was followed by a spate of vertical drilling in low-permeability sandstones. Now, horizontal drilling is tapping new ...