The Office of Technology Assessment (OTA), an analytic support agency of the United States Congress, has examined the process of forecasting future supplies of conventional, domestically produced natural gas in the U.S. lower-48 states to the year 2000. Its investigation focused particularly on the technical sources of uncertainty, including the incomplete geologic understanding of the remaining resources and the difficulties involved in properly interpreting and extrapolating past trends in natural gas discovery. The OTA examined the arguments developed by supply "optimists" and "pessimists" regarding both the size of the recoverable resource base and the speed with which new resources can be discovered and produced. As part of the investigation, resource-base es imates, ranging from those of H. King Hubbert and Richard Nehring to those of the U.S. Geological Survey and the Potential Gas Committee, were reviewed and compared.

The OTA concluded that the credible ranges of estimates for lower-48 resources and future production potential are very wide--430 to 900 tcf for the remaining recoverable resources of conventional gas at near-current prices and technology, and 9 to 19 tcf/yr for the year 2000 production under the same price and technology conditions.