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Science 17 November 1995:
Vol. 270. no. 5239, pp. 1186 - 1189
DOI: 10.1126/science.270.5239.1186
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Reports

Partitioning of Tungsten and Molybdenum Between Metallic Liquid and Silicate Melt

Michael J. Walter (1) and Yves Thibault

The ``excess'' of siderophile elements in Earth's mantle is a long-standing problem in understanding the evolution of Earth. Determination of the partitioning behavior of tungsten and molybdenum between liquid metal and silicate melt at high pressure and temperature shows that partition coefficients (D) vary by two orders of magnitude depending on whether metal segregated from a basaltic or peridotitic melt. This compositional dependence is likely a response to changes in the degree of polymerization of the silicate melt caused by compositional variations of the network-modifying cations Mgand Fe. Silicate melt compositional effects on partition coefficients for siderophile elements are potentially more important than the effects of high pressure and temperature.


M. J. Walter, Geophysical Laboratory and Center for High Pressure Research, Carnegie Institution of Washington, 5251 Broad Branch Road NW, Washington, DC 20015, USA.
Y. Thibault, Department of Earth Sciences, Biology and Geology Building, University of Western Ontario, London, Ontario N6A 5B7, Canada.
(1) To whom correspondence should be addressed at Institute for Study of Earth's Interior, Okayama University, Misasa, Tottori-ken 682-01, Japan.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Partitioning experiments in the laser-heated diamond anvil cell: volatile content in the Earth's core.
A. P Jephcoat, M. A. Bouhifd, and D. Porcelli (2008)
Phil Trans R Soc A 366, 4295-4314
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Partitioning of calcium, magnesium, and transition metals between olivine and melt governed by the structure of the silicate melt at ambient pressure.
B. Mysen (2007)
American Mineralogist 92, 844-862
   Abstract »    Full Text »    PDF »
STRUCTURAL ENVIRONMENTS AROUND MOLYBDENUM IN SILICATE GLASSES AND MELTS. I. INFLUENCE OF COMPOSITION AND OXYGEN FUGACITY ON THE LOCAL STRUCTURE OF MOLYBDENUM.
F. Farges, R. Siewert, G. E. Brown Jr., A. Guesdon, and G. Morin (2006)
Can Mineral 44, 731-753
   Abstract »    Full Text »    PDF »
STRUCTURAL ENVIRONMENTS AROUND MOLYBDENUM IN SILICATE GLASSES AND MELTS. II. EFFECT OF TEMPERATURE, PRESSURE, H2O, HALOGENS AND SULFUR.
F. Farges, R. Siewert, C. W. Ponader, G. E. Brown Jr., M. Pichavant, and H. Behrens (2006)
Can Mineral 44, 755-773
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