A new study by the Bureau of Economic Geology (BEG) at the University of Texas at Austin forecasts that one of the nation’s most productive shale gas basins, the Fayetteville Shale, will continue to be a major contributor to U.S. natural gas supplies for years to come, with eco­nomically recoverable reserves of 18 Tcf through 2050.

The assessment of the Fayetteville Shale, part of a four-basin study of shale gas reserves funded by the Alfred P. Sloan Foundation, follows the same methodology as BEG’s 2013 assessment of natural gas production in the Barnett Shale, the nation’s most commercially developed unconventional gas play. Both studies integrate engi­neering, geology, and economics and are designed to be among the most rigorous assessments to date of produc­tion in U.S. shale gas basins.

Noted is that most other assessments of shale gas reserves have taken a “top down” view of production, relying on aggregate views of average production. In con­trast, this study takes a “bottom up” approach, starting with the production history of every well and then deter­mining what areas remain to be drilled, said Scott Tinker, BEG director and co-principal investigator. The result, he added, yields a more accurate and comprehensive view of the basin.

The BEG team further enhanced the view of the Fayetteville Shale by identifying and mapping six production-quality tiers in the basin and using those tiers to forecast future production. The economic feasibility of production varies across the basin depending on the production quality of the tier. Researchers created and mapped an inventory of future feasible drilling locations based on economics and estimated gas-in-place. BEG plans to complete assessments this year of two other major U.S. shale gas basins, the Haynesville in Arkansas, Louisiana, and Texas and the Marcellus in the Appala­chian region.