The Barnett Shale: Not So Simple After All

Natalie Givens, Hank Zhao, and Dan Steward
Republic Energy Inc, Dallas, Texas

The technological advances made within the last decade have allowed the Barnett Shale to grow from a crazy prospect to being one of the largest onshore natural gas plays within the continental U.S. With an estimated 26.2 TCF gas in place, the Barnett has begun to attract worldwide attention (USGS, 2004). A Barnett well in the heart of the Newark East field has an average depth of 7500’, an Estimated Ultimate Recovery (EUR) of 1.25 BCF, the possibility of multiple fracture stimulations (refracs) and a cost of roughly only $600,000 per vertical well. But don't get too excited yet ... there are many hurdles we must understand to get good Barnett production.

We must know and try to understand several items of importance:

• The maturation pattern of the Barnett in North Texas
• The thickness of the Barnett across the prospective area
• Regional faulting and underlying Ellenberger karsting
• Fracture stimulation (frac) techniques designed to meet the needs of a given area
• A drilling and completion strategy so as not to inundate the Barnett with frac water

Each of these factors has a significant effect on ultimate reserves and must be appreciated with respect to each other.

Reprinted from "Banking on the Permian Basin: Plays, Field Studies, and Techniques".
Robert C. Trentham, ed. West Texas Geological Society Publ. #04-112
Fall Symposium, October 27-29, 2004