A mineral survey of four areas totalling 80 square miles, not included during the 1968-70 examination of the proposed Salmon-Trinity Alps Wilderness, was made by the U.S. Geological Survey and U.S. Bureau of Mines in 1973. Geological Survey personnel mapped the geology and collected stream-sediment and rock samples for spectrographic and chemical analysis; Bureau of Mines personnel examined the known placer and lode claims. The areas examined include: (1) the upper drainage of Red Cap Creek in Humboldt County, adjoining the northwest part of the Salmon-Trinity Alps Primitive Area; (2) an area in Trinity County south of the Primitive Area including the drainage of Big French Creek and the canyon of North Fork Trinity River from Hobo Gulch Forest Camp to the junction with East Fork of North Fork; (3) an area, also south of the Primitive Area and in Trinity County, including East Fork of North Fork from Manzanita Flat to Squaw Gulch, and the drainages of Indian Creek, Squaw Gulch, lower East Branch, and lower Yellow Jacket Creek; (4) the drainage of St. Clair Creek in Siskiyou County north of the Primitive Area; and (5) a small area on New River from the junction of Slide and Virgin Creeks downstream to the mouth of Barron Creek that was previously mapped by the Geological Survey (Hotz and others, 1972) but had not been studied by the Bureau of Mines.
