There was a consensus that technology has in the past reduced, and will continue in the future to reduce, exploration and production costs. In the United States, for example, rigorous application of technology has resulted in the last decade or so in essentially flat supply cost projections. The relatively stable supply costs are due to technology and its impact in reducing production costs (William L. Fisher, "The U.S. Experience in Natural Gas: Revitalization of a Resource Base Thought Exhausted, this volume).

Coalbed methane is playing an increasingly important role in meeting the energy needs of the United States. According to one estimate, this unconventional gas may supply 4-5% of the domestic natural gas in 1994. In the San Juan Basin, Fruitland Formation coal beds contain an estimated 43 to 49 trillion cubic feet (Tcf) of methane. This basin is the most active area of coalbed methane development and production in the United States.

ow-permeability ("tight") reservoir sandstones of the lower Missourian Cleveland formation produced more than 435 billion cubic feet (Bcf) of natural gas through December 1990, mostly from Ochiltree and Lipscomb Counties in the northeastern Texas Panhandle. Although large-scale gas production started in1956, the regional stratigraphic, depositional, and structural setting of the Cleveland is poorly known.