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Research about Idaho, Montana

Source-linked reports with geographic coverage including Idaho, Montana.

At least 91 records · Page 5Linked to original sources
USGS1984

Geochronometric and lead isotope data on samples from the Wallace 1 degree by 2 degrees Quadrangle, Montana and Idaho

Most of the bedrock in the Wallace quadrangle belongs to the Belt Supergroup, a thick (about 18,000 m) sequence of generally fine-grained clastic and carbonate rocks of Middle Proterozoic age. Regional metamorphism prior to Cambrian time prograded the Belt rocks to greenschist facies, and some metal-bearing veins were emplaced in fractures. The Belt rocks were intruded in Late Proterozoic time by basic dikes and sills.

Idaho, Montana↗
USGS1983

Mineral resource potential map of the Selway-Bitterroot Wilderness, Idaho County, Idaho, and Missoula and Ravalli counties, Montana

Mineral resource studies by the U.S. Bureau of Mines and the U.S, Geological Survey indicate that five areas within the Selway-Bitterroot Wilderness have mineral resource potential. Regional studies suggest that three granitic plutons within the wildemess, the Running Creek pluton on the southwestern border of the wildemess, the Painted Rocks pluton on the southern border of the wildemess, and the Whistling Pig pluton in the west-central portion of the wildemess, have low potential for molybdenite deposits, but detailed surface investigations failed to recognize a deposit. Placer deposits in the Elk Summit area on the north side of the wildemess contain subeconomic resources of niobium- (columbium-) bearing ilmenite. A vein on the northeast side of the wildemess at t~e Cliff mine at Saint Joseph Peak contains subeconomic silver-copper-lead resources. The wilderness has no known potential for oil and gas, coal, geothermal resources, or other energy-related commodities.

Idaho, Montana↗
USGS1983

Reconnaissance geologic map of the Selway-Bitterroot Wilderness, Idaho County, Idaho, and Missoula and Ravalli counties, Montana

The Selway-Bitterroot Wilderness covers about 1.25 million acres in east-central Idaho and western Montana (fig. 1). The wilderness lies across the Bitterroot Range, which forms the boundary between Idaho and Montana, and includes large portions of the drainages of the Selway, Lochsa, and Bitterroot Rivers. Elevations range from 1,800 ft on the Selway River near the wilderness boundary to 10,157 ft at Trapper Peak in the Bitterroot Mountains. Cities within 50 min of the wilderness include Missoula, Hamilton, and Salmon on the east, and Orofino and Grangeville on the west. Access to trailheads near the edge of the wilderness is limited to dirt roads.

Idaho, Montana↗
USGS1983

Geochemical maps of the Selway-Bitterroot Wilderness, Idaho County, Idaho, and Missoula and Ravalli counties, Montana

The Selway-Bitterroot Wilderness covers almost 2,000 mi 2 in east-central Idaho and western Montana (fig. 1). The wilderness lies across the Bitterroot Range, which forms the boundary between Idaho and Montana, and includes large portions of the drainages of the Selway, Lochsa, and Bitterroot Rivers. Elevations range from 1,800 ft on the Selway River near the wilderness boundary to 10,157 ft at Trapper Peak in the Bitterroot Mountains. Specific areas within the wilderness mentioned in this report are shown in figure 1.

Idaho, Montana↗
USGS1982

Geophysical survey of the Centennial Mountains Wilderness Study Area and contiguous areas, Beaverhead County, Montana and Clark and Fremont counties, Idaho

Parts of both the Targhee and Beaverhead National Forests are within the study area. Four contiguous parcels of land, totaling about 96,176 acres (38,922 ha) make up the area. The first of these encompasses about 46,126 acres (18,667 ha), is wholly in Montana, and includes an addition by the Bureau of Land Management. The second area, in the Targhee National Forest, consists of some 38,750 acres (15,682 ha) within Idaho. The third and fourth parcels include about 11,300 acres (4,573 ha) in the Beaverhead..and Targhee National Forests that overlies the Mt. Jefferson and Sawtell Peak areas in the eastern part of the Centennial Mountains.

Idaho, Montana↗
USGS1981

Mineral resource potential of the Centennial Mountains Wilderness Study Area and contiguous areas, Idaho and Montana

The Centennial Mountains include parts of Beaverhead County, Montana, and Clark and Fremont Counties, Idaho; the mountains trend east, and the Continental Divide follows their crest (fig. 1). They form a massive, almost impassable barrier between Centennial Valley on the north and the broad expanse of the Snake River Plain on the south. The proposed Wilderness Study Area encompasses the central more rugged part of the mountains and includes parts of both the Targhee and Beaverhead National Forests. Four contiguous parcels of land, totaling about 96,176 acres (38,922 hectares), make up the Wilderness Study Area (fig. 2). The first of these, encompassing about 46,126 acres (18,667 ha), is wholly in Montana (north of the Continental Divide) and consists of the U.S. Bureau of Land Mapagement's Centennial Mountains Instant Study Area. The second area, known as Management Unit 1 of the Centennial Planning Unit of the Targhee National Forest, consists of some 38,750 acres (15,682 ha) within Idaho (south of the Continental Divide). The third and fourth parcels include about 11,300 acres (4,573 ha) of National Forest land which cover the Mt. Jefferson and Sawtell Peak areas in the eastern part of the Centennial Mountains. Both are Forest Service Further Planning roadless areas (Unit 1-962 of the Beaverhead National Forest in Montana—the Mt. Jefferson area, and Unit 4-962 of the Targhee National Forest in Idaho—the Mt. Jefferson West area). Details of the geography and geology of the area are incorporated in a separate map prepared as an integral part of the mineral resource evaluation (Witkind, 1981). Only the more salient details of the geology described in that report are repeated here.

Idaho, Montana↗