Subjective probability appraisal of uranium resources in the state of New Mexico

Abstract

This report presents an estimate of undiscovered uranium resources in New Mexico of 226,681,000 tons of material containing 455,480 tons U$sub 3$$O$$sub 8$. The basis for this estimate was a survey of expectations of 36 geologists, in terms of subjective probabilities of number of deposits, ore tonnage, and grade. Weighting of the geologists' estimates to derive a mean value used a self- appraisal index of their knowledge within the field. Detailed estimates are presented for the state, for each of 62 subdivisions (cells), and for an aggregation of eight cells encompassing the San Juan Basin, which is estimated to contain 92 percent of the undiscovered uranium resources in New Mexico. Ore-body attributes stated as probability distributions enabled the application of Monte Carlo methods to the analysis of the data. Sampling of estimates of material and contained U$sub 3$$O$$sub 8$ which are provided as probability distributions indicates a 10 percent probability of there being at least 600,000 tons U$sub 3$$O$$sub 8$ remaining undiscovered in deposits virtually certain to number between 500 and 565. An indicated probability of 99.5 percent that the ore grade is greater than 0.12 percent U$sub 3$$O$$sub 8$ suggests that this survey may not provide reliable estimates ofmore » the abundance of material in very low-grade categories. Extrapolation to examine the potential for such deposits indicates more than 1,000,000 tons U$sub 3$$O$$sub 8$ may be available down to a grade of 0.05 percent U$sub 3$$O$$sub 8$. Supplemental point estimates of ore depth and thickness allowed derivative estimates of cost of development, extraction, and milling. 80 percent of the U$sub 3$$O$$sub 8$ is estimated to be available at a cost less than $15/lb (1974) and about 98 percent at less than $30/lb. (auth) « less