Circular 134—Coal resources of southern Ute and Ute Mountain Indian reservations, Colorado and New Mexico

By J. W. Shomaker and R. D. Holt, 1973, 22 pp., 9 tables, 17 figs., 1 appendix, sheets.

Provides description and evaluation of the coal resources of this area. The Southern Ute and Ute Mountain Ute Indian Reservations, in southwestern Colorado and northwestern New Mexico, are underlain by coal in three formations of Late Cretaceous age. The Dakota Sandstone contains an estimated 11,733 million tons, the Menefee Formation 13,969 million tons, and the Fruitland Formation 25,331 million tons. About 471 million tons, mostly Fruitland coal, is minable by stripping or augering. Water required for the most likely development of the coal is as much as 18,300 acre feet per year. Some of the remainder of the coal reserve may be minable eventually, and would require far greater amounts of water.

This study was undertaken to define the coal resources belonging to the Southern Ute and Ute Mountain Ute Tribes of Indians. The study considers not only the gross amount of coal available, but also the distribution of coal including thickness of beds, depth, and other criteria of mineability. It also considers the chemical and physical characteristics of the various coal reserve blocks, the amount and quality of water that might be required for development of the coal resources, and the commercial potential and marketability of the coal.

The report presents a practical evaluation of the coal resources. Information from every available source was compiled. Original exploratory work was done where needed. Coal reserves and other interpretive matter were then combined to produce the report desired. Published work was supplemented by measurement of surface geologic sections where necessary, particularly in the eastern and western extremities of the study area. Coal beneath the surface was studied primarily through the use of oil and gas test logs. Some 700 electrical logs, and a number of older sample descriptions and driller's logs were examined to delineate the coalbeds penetrated. Unfortunately, such logs are available for only parts of the coal-bearing areas encompassed by the study; in the remaining area, surface information alone was used. The study area was part of a larger examination and evaluation of the strippable coal reserves of the San Juan Basin. The broad scope of that study did not permit a detailed examination of Ute lands. The present study represents a considerable refinement with respect to strippable reserves.