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PlatesPlate 1.Mineral resource potential map for locatable and leasable commodities Plate 2.High-pass filtered Bouguer gravity anomaly map Plate 3.

Bureau of Mines • Studies Related To WildemessUnder the proVIsions of the Wildemess Act (Public Law 88-577, September 3, 1964) and the Joint Conference Report on Senate Bill 4, 88th Congress, the U.S. Geological Survey and the U.S. Bureau of Mines have been conducting mineral surveys of wilderness and primitive areas. Areas officially designated as "wildemess," "wild," or "canoe" when the act was passed were incorporated into the National Wildemess Preservation System, and some of them are presently being studied. The act provided that areas under consideration for wildemess designation should be studied for suitability for incorporation into the Wildemess System. The mineral surveys constitute one aspect of the suitability studies • . The act directs that the results of such surveys are to be made available to the public and be submitted to the President and the Congress. This report discusses the results of a mineral survey of the Selway-Bitterroot Wildemess in the

This summary highlights the mineral resources of the Forest and is presented to aid land-use planners and other non-scientific personnel.This study was undertaken at the request of the U.S. Forest Service. The USGS assessment involved a team of six scientists with expertise in geology, geochemistry, geophysics, mineral deposits, and resource analysis. The Forest includes part of the Colorado Mineral Belt, one of the most productive areas of base and precious metals in North America.Mining and mineral exploration have played a central role in the history of the Forest since the early 1800's; several world-class mines are either in or adjacent to the Forest, and smaller mines are abundant throughout the Forest.More than $15 billion in metals (at current-day prices) has been produced in mining areas adjacent to or within the Forest.The last producing mine (Oilman mine) ceased its operations in 1981; current mineral-related activity consists of annual assessment work on unpatented mining claims, prospecting, and small-scale mining. Large tracts within the Forest, including Wilderness Areas, have abundant direct and indirect indications of the presence of metallic mineral deposits.Fourteen metallic mineral-deposit types were identified in the Forest; of these, stockwork molybdenum, polymetallic vein, polymetallic replacement, and placer gold deposits are the most likely to have undiscovered resources.The commodities most likely to occur are molybdenum, zinc, lead, silver, gold, and copper.Estimates of the number of undiscovered deposits were made at three probability levels (90,50, and 10 percent); estimated tonnages were determined by statistical iteration with tonnages and grades of known deposits worldwide.Favorable tracts are shown in figure 1 of this report. Probabilistic estimates, which do not take into account the cost of recovery, indicate a mean value of $4.05 billion for undiscovered metallic mineral resources in the Forest (shown below).

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