An Investigation of Olivine Crystal Growth in a Picrite Dyke, Using the Fission Track Method

Paul Henderson, Madeleine Sélo and Dieter Storzer
Department of Mineralogy, British Museum (Natural History), Cromwell Road, London SW7 5BD, UK
Museum National d'Histoire Naturelle, Laboratoire de Minéralogie, 61 rue Buffon, 75005 Paris, France

Abstract: A picrite dyke with an olivine-bearing chilled margin and an olivine-rich centre has been used to test for the presence of a boundary layer around rapidly grown olivine crystals and for any variations in the olivine/melt partition coefficient for uranium as a result of probably different crystal growth rates. The technique of fission-track mapping is shown to be suitable for this kind of study despite the very low uranium concentrations in the olivines. A boundary layer appears to be present around some olivine crystals but it is not a consistent feature. Uranium partition between olivine and melt was not affected by different crystal growth rates, as revealed by different crystal morphologies.

Keywords: olivine • crystal growth • picrite • uranium • fission tracks

Mineralogical Magazine; March 1986 v. 50; no. 355; p. 27-31; DOI: 10.1180/minmag.1986.050.355.04
© 1986, The Mineralogical Society
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