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To characterize mercury (Hg) isotopes and isotopic fractionation in hydrothermal systems we analyzed fluid and precipitate samples from hot springs in the Yellowstone Plateau volcanic field and vent chimney samples from the Guaymas Basin sea-floor rift. These samples provide an initial indication of the variability in Hg isotopic composition among marine and continental hydrothermal systems that are controlled predominantly by mantle-derived magmas. Fluid samples from Ojo Caliente hot spring in Yellowstone range in δ202Hg from − 1.02‰ to 0.58‰ (± 0.11‰, 2SD) and solid precipitate samples from Guaymas Basin range in δ202Hg from − 0.37‰ to − 0.01‰ (± 0.14‰, 2SD). Fluid samples from Ojo Caliente display mass-dependent...
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As part of a multi-year project to infer the pre-mining ground-water quality at Molycorp‘s Questa mine site, surface-water samples of the Red River, some of its tributaries, seeps, and snow samples were collected for analysis of inorganic solutes and of water and sulfate stable isotopes in selected samples. The primary aim of this study was to document diel, storm event, and seasonal variations in water chemistry for the Red River and similar variations in water chemistry for Straight Creek, a natural analog site similar in topography, hydrology, and geology to the mine site for inferring pre-mining water-quality conditions. Red River water samples collected between 2000 and 2004 show that the largest variations...
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Water analyses are reported for ground and surface waters collected at 33 sites on and near Ester Dome, Fairbanks area, central Alaska during 2000-2001. This interdisciplinary study focused on documenting the temporal and spatial chemical variations in arsenic concentrations to elucidate the processes that lead to elevated arsenic concentrations in ground water. Field parameters and water analyses are reported for 17 domestic wells, 13 monitoring well sites, and 3 surface water sites. Sampling occurred during November 2000, February 2001, May 2001, July 2001, and September 2001. Waters in the study area are primarily Ca-HCO3 type, with pH values ranging from 5.97 to 7.87. Dissolved arsenic concentrations ranged...
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