Compound and Elemental Analysis At Valles Caldera - Sulphur Springs Geothermal Area (Musgrave, Et Al., 1989)

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Exploration Activity: Compound and Elemental Analysis At Valles Caldera - Sulphur Springs Geothermal Area (Musgrave, Et Al., 1989)

Exploration Activity Details
Location Valles Caldera - Sulphur Springs Geothermal Area
Exploration Technique Compound and Elemental Analysis
Activity Date - 1989

Usefulness useful
DOE-funding Unknown

Exploration Basis
A series of core holes were drilled from 1984 to 1988 as a part of the Continental Scientific Drilling Program (CSDP) to better understand the stratigraphy, structure, hydrothermal alteration, and subsurface architecture of the Valles caldera. Several authors have reported results from these core holes, including Goff et al. (1986, 1987), Gardner et al. (1987, 1989), Hulen & Nielson (1985), Hulen et al. (1988, 1989), Musgrave et al. (1989), Rowley et al. (1987), Shevenell et al. (1988), and Starquist (1988).
Core from hole VC-2A was sampled every 16 m over the entire length of the hole for compound and elemental analysis. Whole rock isotope samples were taken from these split core intervals, and vein quartz and carbonate samples for isotopic analysis were hand-picked from vein material. SiO2, TiO2, Al2O3, Fe2O3, MnO, MgO, CaO, K2O, Na2O, P2O5, Ba, Sr, Rb, V, Cr, Ni, Zn, Y, Zr, and Nb were analyzed by X-ray Fluorescence spectroscopy (XRF). Ag, Al, As, Au, Ba, Br, Ca, Ce, Cl, Co, Cr, Cs, Cu, Dy, Eu, Fe, Ga, Hf, Hg, I, In, K, Lu, Mg, Mn, Mo, Na, Nd, Rb, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, Ti, U, V, W, Yb, Zn, and Zr were measured using Instrumental Neutron Activation Analysis (INAA). Select samples were analyzed for Au and Hg using Fire Assay/Atomic Absorption analysis (AA). Cu, Pb, Zn, Mo, Ag, Co, Ni, Cr, Mn, W, Bi, As, and Sb were also analyzed using Inductively Coupled Plasma spectroscopy (ICP).
> Seven water samples collected from VC-1 and VC-2A were analyzed for their major element and isotopic contents. Water sampling methods are as follows: '1) 125-mL filtered unacidified water for anions; 2) 125-mL filtered acidified water for cations; 3) a 500-mL glass bottle of unfiltered water for tritium analysis; 4) a 30-mL glass bottle of unfiltered water for stable isotope analysis; 5) a 60-mL bottle of filtered diluted (1:5) water for SiO2; 6) a 250-mL bottle of unfiltered water with 10 mL NH4OH saturated with SrCl2 added for determination of 13C-HCO3; and 7) a 250-mL bottle of unfiltered water with 5 mL of formaldehyde added for the determination of 18O-SO4' (Musgrave et al., 1989).
> Chemical analyses of the water samples were performed using the following methods: colorimetry using ammonium molybdate for SiO2; ICP analysis for Al, As, Ba, Ca, Fe, K, Li, Mg, Mn, Mo, Na, Si, Sr, and Zn; AA spectroscopy using a graphite furnace for Ag, Al3+, Cd, Co, Cr, Cu, Ni, Pb, and Rb; ion chromatography for Br, Cl, NO3, PO4, and SO4; colorimetry using azomethine-H or ICP analysis for B; ion selective electrode for F, S2-, NH4, and dissolved O2; flame AA for low-level Na, K, Li; and titration with H2SO4 for HCO3 and CO3.


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