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Research about Humboldt, Nevada

Source-linked reports with geographic coverage including Humboldt, Nevada.

6 recordsLinked to original sources
USGS1981

Permian and Triassic rocks near Quinn River Crossing, Humboldt County, Nevada

Permian and Triassic rocks near Quinn River Crossing, Humboldt County, Nevada, consist of four structural blocks: (1) a Lower Permian volcanic block; (2) a Permian(?) chert-arenite block; (3) a Lower Permian limestone block; and (4) a Permian and Triassic block. The contacts between the Permian volcanic block and the others are interpreted as thrust faults or glide surfaces. None of these rocks are metamorphosed, in contrast to those of the surrounding mountain ranges. Each of the blocks is lithically similar in some respects to rocks of the Osgood Mountains area 80 km to the southeast. The fusulinid and brachiopod faunas of two of the blocks display affinities to those of the McCloud Limestone of northern California and the Coyote Butte Limestone of central Oregon, and the fauna of another block has elements in common with autochthonous rocks of eastern Nevada and Utah. All four blocks probably are allochthonous with respect to the rocks exposed in the surrounding mountain ranges, but their points of origin remain obscure. The rocks at Quinn River Crossing provide a link among the Permian rocks of north-central Nevada, northern California, and central Oregon and a possible key to their original relations, but more comparative data are needed.

Nevada↗
USGS1974

K-Ar Age Relations of Granodiorite Emplacement and Tungsten and Gold Mineralization near the Getchell Mine, Humboldt County, Nevada

A granodiorite stock intrudes complexly folded and thrust-faulted Paleozoic sedimentary rocks in the Osgood Mountains of eastern Humboldt County, Nevada. Within the metamorphic aureole surrounding the pluton, the sedimentary rocks are converted to cordierite hornfels and marble; tungsten-bearing tactites developed along the contacts of the granodiorite. Cutting the granodiorite and sedimentary rocks is the Getchell fault, along which the disseminated gold ore bodies of the Getchell mine are localized. K-Ar ages of the granodiorite, andesite porphyry, tungsten-bearing tactites, and altered granodiorite from the Getchell mine indicate that emplacement, alteration, and mineralization are all part of a magmatic-thermal episode which took place approximately 90 m.y. ago.

Nevada↗
USGS1973

Galkhaite, (Hg,Cu,Tl,Zn) (As,Sb)S2, from the Getchell mine, Humboldt County, Nevada

The first reported occurrence in the United States of galkhaite (Hg,Cu,Tl,Zn)(As,Sb)S 2 is at the Getchell mine, Humboldt County, Nev. The mineral occurs as brownish-black cubes associated with graphite, pyrite, and realgar. In polished section galkhaite is grayish white and isotropic with a deep-red internal reflection; reflectivity at 590 nm is 21.6 percent. Spectrographic analysis gave Hg 42 percent, Cu 5 percent, Zn 1.5 percent, Fe 0.7 percent, Tl 5 percent, As 24 percent, Sb 0.3 percent, and S (by difference) 21.3 percent. The mineral is cubic, a=10.36, and the strong lines of the X-ray powder pattern are 2.99 (100), 4.21 (90), 2.76 (80), 1.831 (70), 7.25 (60), 2.58 (40), 1.561 (40). The pattern is very similar to that of tetrahedrite except for the strong lines at 7.25, 4.21, and 2.76.

Nevada↗
USGS1971

Geochemical, aeromagnetic, and generalized geologic maps showing distribution and abundance of mercury and arsenic, Golconda and Iron Point quadrangles, Humboldt County, Nevada

Detailed geologic and geochemical studies of the four 7 1/2-minute wuadrangles that make up the Edna Mountain 15-minute quadrangle in Humboldt County, Nevada, were begun druring the 1969 summer field season. The objectives of the project are to map the geology of this structurally complex area at 1:24,000 scale and to determine the regional distribution and abundance of metals in rocks of the area and the factors that control the distribution and abundance of those metals. Tungsten-bearing hot-spring tufa, metalliferous black shale in Ordovician rocks, base-metal and barite deposits in Paleozoic sedimentary rocks, and copper-molybdenum in granodiorite plutons of Creataceous age occur in the Edna Mountain dare. None of these deposits have been of much economic significance, although tungsten was mined from the hot-spring deposits during World War II.

Nevada↗
USGS1954

Hydraulic characteristics of aquifers penetrated by irrigation wells in the vicinity of Orovada, Humboldt County, Nevada, 1953

During the period April 21-23, 1953, a pumping test was made on several irrigation wells penetrating alluvium about a mile southwest of Orovada, Nev., in order to determine the hydraulic characteristics of the aquifers commonly penetrated by wells in that vicinity. The test was made by the writer, engineer, and J.L Poole, geologist, United States Geological Survey, as part of an investigation of the ground-water resources of Nevada being by the U.S Geological Survey in cooperation with the State Engineer. Much recent interest in the development of underground water by pumping in the Orovada area made it desirable to make the pumping test in order to obtain data that might be helpful in the proper planning of future development.

Nevada↗