Geochemical analyses of rock and soil samples, Eureka Mining District and vicinity, Eureka and White Pine Counties, Nevada

Abstract

acknowledge the help of T. B. Nolan, who provided valuable geologic orientation in the field. DESCRIPTION OF TABLE 1. Rock geochemical analyses Col. 1 sample Sample numbers corresponding to numbers shown on plate 1. Cols. 2-3 X-Coord. and Y-Coord. The X value is an E-W distance and the Y value, a N-S distance. These are distances in feet using the 10,000-foot grid based on the Nevada coordinate system, east zone, as given on the base maps for plate 1. Multiply values given in the table by 10 to get actual map coordinates. Cols. 4-24 S-(element symbol) Spectrographic determinations. All values are given in parts per million (ppm) unless a "%" sign is present. Col. 25 AA-Au Atomic absorption determinations. Gold values in ppm. Col. 26 Inst-HG Flameless atomic absorption determinations. Mercury values in ppm. Cols. 27-28 AA-(element symbol) Atomic absorption determinations. Values, in ppm, for lead, zinc, and silver, respectively. Cols. 30-31 CM-(element symbol) Colorimetric determinations. Values, in ppm, for arsenic and antimony, respectively. DESCRIPTION OF TABLE 2. Fine-and coarse-soil geochemical analyses Col. 1 sample Sample numbers, for fine-and coarse-soil pairs, corresponding to numbers shown on plate 1. Cols. 2-3 X-Coord. and Y-Coord. The X value is an E-W distance and the Y value, a N-S distance. These are distances in feet using the 10,000-foot grid based on the Nevada coordinate system, east zone, as given on the base maps for plate 1. Multiply values given in the table by 10 to get actual map coordinates. Cols. 4-27 S-(element symbol) Spectrographic determinations. All values are given in parts per million (ppm) unless a "%" sign is present. Col. 28 AA-Au Atomic absorption determinations. Gold values in ppm. Col. 29 Inst-HG Flameless atomic absorption determinations. Mercury values in ppm. Cols. 30-32 AA-(element symbol) Atomic absorption determinations. Values, in ppm, for lead, zinc, and silver, respectively. Cols. 33-34 CM-(element symbol) Colorimetric determinations. Values, in ppm, for arsenic and antimony, respectively. Leaders (-) indicate that no analysis was made for that particular sample and element.

Geochemical and mineralogical study of the Red Mountain porphyry copper-molybdenum deposit and vicinity, Santa Cruz County, Arizona

“…In an earlier study, a regional multielement soil survey was conducted in the vicinity of Eureka, Nevada, an area with a history of overlapping mineralizing events. Factor analysis successfully identified and classified two suites of elements: a silver-rich base-metal suite (Ag, Cu, Pb, Sb, and Zn) of the Cretaceous Period and a Carlin-type gold suite (Au, As, Hg, and Sb) of the Tertiary Period (Chaffee, 1987;Shawe and Nolan, 1989).…”

Hydrogeochemical studies of historical mining areas in the Humboldt River basin and adjacent areas, northern Nevada

“…The slag piles may contain high concentrations of potentially toxic metals, but leach tests of slags generally show these materials to be unreactive (Nash and others, 1996;Nash, 2002a). The extent and composition of dust fallout has not been studied, except at Eureka (Chaffee, 1987), where it is substantial and in need of further study. However, there is anecdotal information that the dust contaminants may dissipate by natural processes over about 75-100 years.…”

Historic mills and mill tailings as potential sources of contamination in and near the Humboldt River basin, northern Nevada

“…The environmental concerns regarding these smelters include possible contamination of soils by particulates from smoke. A detailed geochemical study by Chaffee (1987) included 593 soil samples in the district with a goal of finding exploration guides in an area of smelter contamination. The contamination was shown to cover an area of about 3 km by 6 km, but the magnitude of contamination was not defined.…”