Hydrogen in nominally anhydrous crustal minerals

摘要: Systematic infrared and nuclear magnetic resonance investigations of common crustal minerals were undertaken to better understand the geologic significance minor components structural hydrous species within these nominally anhydrous minerals. The absolute hydrogen concentration in three alkali feldspars eight plagioclase samples was measured with 1H spectroscopy. The mid-infrared integral absorption coefficient determined be 15.3 ? 0.7 ppm-1?cm-2, allowing quantitative analysis OH H2O A survey igneous found that contain (0-512 ppm H2O), (0-1350 NH4+ (0-1500 NH4+) groups as well fluid inclusions alteration products. Composition crystal structure influence type can incorporated into feldspars, but speciation is at least partially by environment. diffusivity H OH-bearing 800-1000?C (D0=5.7?2.5x10-4 m2/sec Q=224?33 kJ/mol). millimeter-sized volcanic feldspar phenocryst would expected lose a significant proportion its on timescale typical eruption (hours weeks). The structures compositions low albite ussingite, Na2AlSi3O8(OH), are similar. strong bonding ussingite fundamentally different from environment feldspars. Comparison spectra isomorphs reedmergnerite, NaBSi3O8, suggest both through protonation most underbonded oxygen site. The diopside for four granulite facies siliceous marble Adirondacks, New York. Diopside increases monotonically increasing estimated water fugacity each outcrop. Hydrogen correlated Ti zoned grossular skarn garnets Birch Creek, CA. Decrease garnet cores rims may related solubility skarn-forming fluid. Skarn an NY, wollastonite ore deposit exhibit large range concentrations broadly rock due recrystallization partial dehydration.