Water produced from oil, gas, and geothermal reservoirs contains natural radioactivity that ranges from background levels to levels found in uranium mill tailings.

Five coal basins in the Rocky Mountain Foreland of the western United States--San Juan, Greater Green River, Piceance, Powder River, and Raton--contain, by virtue of their tremendous coal tonnage, 522 Tcf (14.7 Tm3) coalbed gas resources, or 77 percent of the nation's total of 675 Tcf (19.1

Canyon sandstones form a prolific low-permeability gas play in the Val Verde Basin of southwest Texas. Exploration and development activity is at a high level, but little published information on Canyon geology is available.

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.

Geologic and engineering studies were conducted within fluvial/deltaic strata of a mature South Texas field to determine the impact of reservoir compartmentalization on secondary gas recovery. Stratton is one of several mature South Texas fields containing fluvial and deltaic gas reservoirs.

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.