Search Results - "Webster, James D."

Accumulation of magnetite by flotation on bubbles during decompression of silicate magma by Knipping, Jaayke L., Webster, James D., Simon, Adam C., Holtz, François

“…Magnetite (Fe 3 O 4 ) is an iron ore mineral that is globally mined especially for steel production. It is denser (5.15 g/cm 3 ) than Earth’s crust (~2.7 g/cm…”
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A composition-independent quantitative determination of the water content in silicate glasses and silicate melt inclusions by confocal Raman spectroscopy by Zajacz, Zoltán, Halter, Werner, Malfait, Wim J., Bachmann, Olivier, Bodnar, Robert J., Hirschmann, Marc M., Mandeville, Charles W., Morizet, Yann, Müntener, Othmar, Ulmer, Peter, Webster, James D.

“…A new approach was developed to measure the water content of silicate glasses using Raman spectroscopy, which is independent of the glass matrix composition…”
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Amphibole-, Clinopyroxene- and Plagioclase-Melt Partitioning of Trace and Economic Metals in Halogen-Bearing Rhyodacitic Melts by Iveson, Alexander A, Rowe, Michael C, Webster, James D, Neill, Owen K

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Major Element and Halogen (F, Cl) Mineral–Melt–Fluid Partitioning in Hydrous Rhyodacitic Melts at Shallow Crustal Conditions by Iveson, Alexander A, Webster, James D, Rowe, Michael C, Neill, Owen K

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Magmatic–hydrothermal fluids and volatile metals in the Spirit Lake pluton and Margaret Cu–Mo porphyry system, SW Washington, USA by Iveson, Alexander A., Webster, James D., Rowe, Michael C., Neill, Owen K.

“…The halogen-bearing minerals tourmaline, amphibole, and biotite formed during magmatic–hydrothermal processes associated with the late-stage cooling of the…”
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The impact of dissolved CO2 on bubble nucleation in water-poor rhyolite melts by Gardner, James E., Webster, James D.

“…Volcanic eruptions of H2O-poor rhyolite are enigmas, because gas bubbles are needed to drive eruptions, but experimental evidence suggests that bubbles cannot…”
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Partitioning behavior of chlorine and fluorine in the system apatite-silicate melt-fluid by Mathez, Edmond A., Webster, James D.

“…The partitioning behavior of Cl among apatite, mafic silicate melt, and aqueous fluid and of F between apatite and melt have been determined in experiments…”
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Stable isotope and petrologic evidence for open-system degassing during the climactic and pre-climactic eruptions of Mt. Mazama, Crater Lake, Oregon by Mandeville, Charles W., Webster, James D., Tappen, Christine, Taylor, Bruce E., Timbal, Adrian, Sasaki, Akira, Hauri, Erik, Bacon, Charles R.

“…Evaluation of the extent of volatile element recycling in convergent margin volcanism requires delineating likely source(s) of magmatic volatiles through…”
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Formation of extremely F-rich hydrous melt fractions and hydrothermal fluids during differentiation of highly evolved tin-granite magmas: a melt/fluid-inclusion study by Thomas, Rainer, F rster, Hans-J rgen, Rickers, Karen, Webster, James D.

“…Quartz crystals from topaz-zinnwaldite-albite granites from Zinnwald (Erzgebirge, Germany) contain, in addition to primary and secondary fluid inclusions…”
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Exsolution of magmatic volatile phases from Cl-enriched mineralizing granitic magmas and implications for ore metal transport by Webster, James D.

“…To understand Cl dissolution in aluminosilicate liquids and the exsolution of Cl-rich magmatic volatile phases, experiments were conducted to determine the…”
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Formation of cordierite-bearing lavas during anatexis in the lower crust beneath Lipari Island (Aeolian arc, Italy) by Di Martino, Corrado, Forni, Francesca, Frezzotti, Maria Luce, Palmeri, Rosaria, Webster, James D., Ayuso, Robert A., Lucchi, Federico, Tranne, Claudio A.

“…Cordierite-bearing lavas (CBL;~105 ka) erupted from the Mt. S. Angelo volcano at Lipari (Aeolian arc, Italy) are high-K andesites, displaying a range in the…”
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Petrology and geochemistry of ca. 2100–1000 a.B.P. magmas of Augustine volcano, Alaska, based on analysis of prehistoric pumiceous tephra by Tappen, Christine M., Webster, James D., Mandeville, Charles W., Roderick, David

“…Geochemical and textural features of whole-rock samples, phenocrysts, matrix glasses, and silicate melt inclusions from five prehistoric pumiceous tephra units…”
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Melt inclusions in quartz from an evolved peraluminous pegmatite: Geochemical evidence for strong tin enrichment in fluorine-rich and phosphorus-rich residual liquids by Webster, James D., Thomas, Rainer, Rhede, Dieter, Förster, Hans-Jürgen, Seltmann, Reimar

“…We have investigated the magmatic evolution of a late-stage, F- and P-rich, pegmatite-forming aluminosilicate liquid and the geochemical controls on magmatic…”
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Experimental investigation of H2O and Cl- solubilities in F-enriched silicate liquids; implications for volatile saturation of topaz rhyolite magmas by Webster, James D, Rebbert, Carolyn R

“…To interpret the degassing of F-bearing felsic magmas, the solubilities of H2O, NaCl, and KCl in topaz rhyolite liquids have been investigated experimentally…”
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Fluid-melt trace-element partitioning behaviour between evolved melts and aqueous fluids: Experimental constraints on the magmatic-hydrothermal transport of metals by Iveson, Alexander A., Webster, James D., Rowe, Michael C., Neill, Owen K.

“…The fluid-melt partition coefficients of ten trace metals (Li, Mn, Cu, Zn, Rb, Sr, Mo, W, and Pb, along with K) between hydrous evolved melts and coexisting…”
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Partitioning behavior of chlorine and fluorine in the system apatite–melt–fluid. II: Felsic silicate systems at 200 MPa by Webster, James D., Tappen, Christine M., Mandeville, Charles W.

“…Hydrothermal experiments were conducted to determine the partitioning of Cl between rhyolitic to rhyodacitic melts, apatite, and aqueous fluid(s) and the…”
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Partitioning behavior of chlorine and fluorine in felsic melt–fluid(s)–apatite systems at 50MPa and 850–950°C by Doherty, Angela L., Webster, James D., Goldoff, Beth A., Piccoli, Philip M.

“…The partitioning of Cl between apatite, felsic melts, and aqueous fluids (vapor±brine), and the partitioning of F between apatite and felsic melt were…”
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Chlorine and felsic magma evolution: Modeling the behavior of an under-appreciated volatile component by Webster, James D., Iveson, Alexander A., Rowe, Michael C., Webster, Paul M.

“…Research on magmatic Cl has proven useful for understanding melt evolution, degassing, and other igneous processes. Magmatic Cl behavior varies strongly with…”
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Secondary ion mass spectrometry for the determination of δ37Cl by Godon, Arnaud, Webster, James D, Layne, Graham D, Pineau, Françoise

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Structure of Cl-containing silicate and aluminosilicate glasses: A 35Cl MAS-NMR study by Sandland, Travis O., Du, Lin-Shu, Stebbins, Jonathan F., Webster, James D.

“…Chlorine-35 magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectra were collected at 14.1 and 18.8 Tesla fields to determine the atomic scale…”
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