Three recent case studies in which Prospector II was used illustrate a variety of constructive responses that contribute to regional mineral resource assessments. The case studies included a group of precious-metal vein deposits in the Quartzville Mining District in Oregon, United States; a stratabound gold-silver deposit in Manitoba, Canada; and an Archean tin deposit from Western Australia. In each case, the objective was to see how Prospector II would classify the deposit in terms of deposit models in the Cox-Singer compendium. The precious-metal vein deposits in the Quartzville Mining District were interpreted by Prospector II to be part of a larger system likely to contain porphyry copper deposits. The stratabound gold-silver deposit in Manitoba fit the description of the Homestake gold deposit model. The Archean tin deposit from Western Australia bore little resemblance to any of the tin deposit models in the Cox-Singer compendium. In recent years, quantitative mineral resource assessments have gained recognition among land managers and national policymakers, who have found that numerical measures of potential mineral values are essential when considering alternative strategies. Such quantitative assessments allow land managers to plan optimum use of public lands and allow national policymakers to assess the need for securing long-term mineral supplies from international sources. In addition, quantitative assessments encourage the discovery and development of new deposits. Significant advances have been made in developing new techniques for the quantitative assessment of metallic mineral resources (Drew et al, 1986; Reed et al., 1989). In large part, these techniques are based on an earlier method of regional mineral resource assessment proposed by Singer (1975) and subsequently applied to areas in Alaska. The technique is based on the size distribution of mineral deposits of specified geologic types and on the probability of deposit occurrence. This approach to the quantitative assessment of undiscovered mineral resources is being applied to many of the mineral resource assessments being carried out by the U.S. Geological Survey (USGS) (Singer and Cox, 1988). Critical in this approach to quantitative assessment is the geologist's ability to relate the geologic environment in an area to specific deposit types.
Geology and mineral resources of Iditarod Mining district, Iditarod B-4 and eastern B-5 quadrangles, west-central Alaska