Hostname: page-component-6bf8c574d5-xtvcr Total loading time: 0 Render date: 2025-02-26T17:38:27.539Z Has data issue: false hasContentIssue false
  • English
  • Français

Rare-earth partition between allanite and glass in the obsidian of Sandy Braes, Northern Ireland

Published online by Cambridge University Press:  05 July 2018

C. K. Brooks ,
P. Henderson  and
J. G. Rønsbo
C. K. Brooks
Affiliation:
Institut for Petrologi, Øster Voldgade 10, DK-1350 København K, Denmark
P. Henderson
Affiliation:
Department of Mineralogy, British Museum (Natural History), Cromwell Road, London SW7 5BD, UK
J. G. Rønsbo
Affiliation:
Institut for Mineralogi, Øster Voldgade 5–7, DK-1350 København K, Denmark
Get access Rights & Permissions [Opens in a new window]

Abstract

Allanite phenocrysts and co-existing glass from the perlitic obsidian of Sandy Braes have been analysed for nine rare earths (RE), uranium, and thorium by instrumental neutron activation analysis and for the major elements by electron microprobe. The chondritenormalized RE plot for the allanite shows a steep slope with a negative Eu anomaly. Allanite/glass partition coefficients show a smooth variation with ionic radius (except for Eu), the variation spanning two orders of magnitude. The partitioning behaviour, which is distinct from that shown by the RE in sphene, apatite, and zircon, can be explained by the allanite structure. The pronounced affinity of the light RE for allanite makes this an important mineral in considerations of RE concentrations during the evolution of granitic liquids.

Type
Research Article
Information
Mineralogical Magazine , Volume 44 , Issue 334 , June 1981 , pp. 157 - 160
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1981

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Branch, C. D. (1966). Bull. Bur. Miner. Resour. Geol. Geophys. Aust. 76, 158 pp.Google Scholar
Brooks, C. K. and Rucklidge, J. C. (1976). Meddr. Grønland, 197(3), 27 pp.Google Scholar
Cameron, I. B. and Sabine, P. A. (1969). Rep. Inst. Geol. Sci. 69/6, 15 pp.Google Scholar
Deer, W. A., Howie, R. A., and Zussman, J. (1962), Rock-forming minerals. Vol. 1. London (Longmans), New York (Wiley).Google Scholar
Dollase, W. M. (1971). Am. Mineral. 56, 447-64.Google Scholar
Duggan, M. B. (1976). Mineral. Mag. 40, 652-3.CrossRefGoogle Scholar
Exley, R. A. (1980). Earth Planet. Sci. Letters, 48, 97-110.CrossRefGoogle Scholar
Fitch, F. J. and Hurford, A. J. (1977). Proc. Geol. Assoc. 88, 267-74.CrossRefGoogle Scholar
Hanson, G. N. (1978). Earth Planet Sci. Letters, 38, 26-43.CrossRefGoogle Scholar
Hellman, P. L. and Green, T. H. (1979). Ibid. 42, 191-201.Google Scholar
Henderson, P. (1979). Mineral. Mag. 43, 399-404.CrossRefGoogle Scholar
Henderson, P. (1980). Contrib. Mineral. Petrol. 72, 81-5.CrossRefGoogle Scholar
Henderson, P. and Williams, C. T. (in press). Application of intrinsic Ge detectors to the instrumental neutron activation analysis for rare earth elements in rocks and minerals. Journ. Radioanal. Chem.Google Scholar
Hildreth, W. (1979). Spec. Pap. Geol. Soc. Am. 180, 43-75.Google Scholar
Izett, G. A. and Wilcox, R. E. (1968). Am. Mineral. 53, 1558-67.Google Scholar
Jensen, B. B. (1967). Norsk. Geol. Tidsskr. 47, 9-19.Google Scholar
Nagasawa, H. (1970). Earth Planet. Sci. Letters, 9, 359-64.CrossRefGoogle Scholar
Old, R. A. (1975). Bull. Geol. Surv. Gt. Br. 51, 21-40.Google Scholar
Pedersen, A. K., Engel, J., and Rensbo, J. G. (1975). Lithos, 8, 255-68.Google Scholar
Sabine, P. A. (1970). Rep. Inst. Geol. Sci. 70/11, 8 pp.Google Scholar
Schmincke, H.-H. (1976). In Kunkel, G. (ed.), Biooeography and Ecology in the Canary Islands. Monographiae Biologicae, 30, 67. Junk, W., The Hague.Google Scholar
Shannon, R. D. and Prewitt, C. T. (1969). Acta Cryst. B 25, 925-46.CrossRefGoogle Scholar
Wakita, H., Rey, P., and Schmitt, R. A. (1971). Proc. Second Lunar Sci. Conf., Geochim. Cosmochim. Acta Suppl. 2, 2, 1319-29.Google Scholar