Utility of Rocky Mountain Tight Gas Sand Resource Assessments: Data Sources, Methodologies and End Users

J. B. Curtis, Department of Geology and Geological Engineering, Colorado School of Mines, 1516 Illinois Street, Golden, CO 80401, phone: 303 273 3887, [email protected]

Projections by United States government and gas industry research organizations indicate that U.S. gas consumption could increase up to 40% from the current 23 trillion cubic feet by the year 2025. The Rocky Mountain region contains the largest remaining Lower-48 potential gas resource, outside of the U. S. Gulf Coast. The bulk of this assessed resource is thought to be present in tight gas sands or coal seams. With a projected decline in more conventional U.S. gas production, and a stabilization or decline in Canadian imports, these resources are assumed to be the next gas supply increment available (and required) to meet the Nation's needs, prior to the possible delivery of Alaskan gas, expansion of LNG imports and any future exploitation of natural gas hydrates.

Recent work by the geologic community has questioned both the existence and producibility of significant tight gas sand resources. In turn, this controversy directly impacts the validity and utility of published resource assessments.

This paper examines Rocky Mountain tight gas sand resource assessments completed by the U.S. Geological Survey, Energy Information Administration of the U.S. Department of Energy, National Petroleum Council and the U.S. Potential Gas Committee. The practical utility of these assessments is considered in light of:

• Data sources employed by each organization • Scale of assessment unit – formation, play or province-level • Assessment methodologies • The requirements of end users – E&P companies, the financial community and public policy decision makers