Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Law, K. M. Articles by Ragnarsdottir, K. V. Search for Related Content GeoRef GeoRef Citation

Trace element partitioning between wollastonite and silicate-carbonate melt

CETSEI, Department of Earth Sciences, University of Bristol, Wills Memorial Building, Queens Road, Bristol BS8 1RJ, UK

^* E-mail: jon.blundy{at}bris.ac.uk

We have performed an experimental study of the influence of varying size and charge on cation partitioning between wollastonite and silicate-carbonate melt in the system CaCO₃-SiO₂. The experimental conditions (3 GPa, 1420°C) lie close to the wollastonite II tc/I tc phase boundary. Results for 1+, 2+, 3+ and 4+ partitioning show parabolic dependence of partition coefficients on ionic radius, which can be fitted to the elastic strain model of Blundy and Wood (1994), wherein partitioning is described using three parameters: site radius (r₀), site elasticity (apparent Young’s Modulus) and the ‘strain-free’ partition coefficient (D₀) for an element with radius r₀. The apparent Young’s Modulus of the Ca site in wollastonite, obtained from modelling the 2+ partitioning data, is 99 ± 3 GPa, similar to the bulk-crystal value for the polymorph wollastonite I tc. r₀ decreases with increasing charge on the substituent cation, while D₀ also shows an approximately parabolic dependence on charge, with a maximum for 2+ cations. Partition coefficients for divalent cations Zn, Co, Fe, Cd, Mn and Pb are lower than would be predicted from their ionic radii alone, indicating a preference for the melt. This may be a consequence either of cation-carbonate complexation in the melt, or of the more distorted nature of cation co-ordination environments in melts.

KEYWORDS: trace element partitioning, wollastonite, metasomatism, carbonate melt

This article has been cited by other articles:

				J. ADAM and T. GREEN The influence of pressure, mineral composition and water on trace element partitioning between clinopyroxene, amphibole and basanitic melts European Journal of Mineralogy, October 1, 2003; 15(5): 831 - 841. [Abstract] [Full Text] [PDF]

				S. Klemme, S. Klemme, and C. Dalpe Trace-element partitioning between apatite and carbonatite melt American Mineralogist, April 1, 2003; 88(4): 639 - 646. [Abstract] [Full Text] [PDF]

				A. P. Jones Carbonatite Thematic Set Mineralogical Magazine, August 1, 2000; 64(4): 581 - 582. [Full Text] [PDF]