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Magmatic Garnets in the Cairngorm Granite, Scotland

Published online by Cambridge University Press:  05 July 2018

T. N. Harrison
T. N. Harrison*
Affiliation:
Department of Geology and Mineralogy, University of Aberdeen, Aberdeen AB9 1AS, Scotland
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Abstract

Small, euhedral Mn-rich garnets (32–52 mol. % spessartine) from the Cairngorm granite, Eastern Grampian Highlands, Scotland, are considered to be of magmatic origin and have not been derived from the assimilation of metasedimentary material, despite their occurrence largely at the margins of the pluton. Similar garnets also occur in a late cross-cutting aplite sheet. The garnets in the granite crystallized early in the sequence and are thought to have formed in response to the ponding of Mn-rich fluids against the wall of the pluton. This Mn enrichment of the fluid phase continued throughout the evolution of the pluton, resulting in Mn-rich biotites and opaque oxides and the localized crystallization of Mn-rich garnets in aplite. Garnet contains up to 1.67 wt. % Y, but has not played a major role in the geochemical evolution of the Cairngorm granite, which has high SiO2 (72–77%) and is enriched in Y and HREE. Chemical analyses of garnets, biotites and rocks are given.

Keywords

magmatic garnetsspessartine-almandineCairngorm graniteScotlandMn enrichmentyttriumbiotitesfluid phase
Type
Mineralogy
Information
Mineralogical Magazine , Volume 52 , Issue 368 , December 1988 , pp. 659 - 667
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1988

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References

Abbott, R.N. (1981) Can. Mineral. 19, 103-10.Google Scholar
Allan, B.D. and Clarke, D.B. (1981) Ibid. 19, 19-24.Google Scholar
Baldwin, J.R. and von Knorring, O. (1983) Ibid. 21, 683-8.Google Scholar
Barritt, S.D. (1983) The controls of radioelement distribution in the Etive and Cairngorm granites: implications for heat production. Unpubl. Ph.D. thesis, Open University.Google Scholar
Barrow, G. and Cunningham-Craig, E.H. (1913) Mem. Geol. Surv. Scotland, 65.Google Scholar
Brown, G.C. and Locke, C.A. (1979) Earth Planet. Sci. Lett. 45, 69-79.CrossRefGoogle Scholar
Buddington, A.F. and Lindsley, D.H. (1964) J. Petrol. 5, 310-57.CrossRefGoogle Scholar
Chappell, B.W. and White, A.J.R. (1974) Pacific Geol. 8, 173-4.Google Scholar
Collins, W.J., Beams, S.D., White, A.J.R., and Chappell, B.W. (1982) Contrib. Mineral. Petrol. 80, 189-200.CrossRefGoogle Scholar
Day, H.W. and Fenn, P.M. (1982) J. Geol. 90, 485-507.CrossRefGoogle Scholar
de Pieri, R. and Jobstraibizer, P.G. (1983) Neues Jahrb. Mineral. Abh. 148, 588-2.Google Scholar
Felsche, J. and Hermann, A.G. (1970) In Handbook of Geochemistry (Wedepohl, K.H., ed.) 11-5. (Springer- Verlag, Berlin).Google Scholar
Ferry, J.M. and Spear, F.S. (1978) Contrib. Mineral. Petrol. 66, 113-17.CrossRefGoogle Scholar
Green, T.H. (1977) Ibid. 65, 596-7.Google Scholar
Harmon, R.S., Pankhurst, R.J., Plant, J.A., and Simpson, P.R. (1984) Proc. Field Conf. Open Magmarie Systems, ISEM Southern Methodist University, 723.Google Scholar
Harrison, T.N. (1987a) Scott. J. Geol. 22, 303-14.CrossRefGoogle Scholar
Harrison, T.N. (1987b) The evolution of the Eastern Grampians granites. Unpubl. Ph.D. thesis, University of Aberdeen.Google Scholar
Harry, W.T. (1965) Scott. J. Geol. 1, 1-8.CrossRefGoogle Scholar
Hildreth, W. (1981) J. Geophys. Res. 86, 101-53.2.Google Scholar
Hsu, L.C. (1968) J. Petrol. 9, 40-83.CrossRefGoogle Scholar
Jaffe, H.W. (1951) Am. Mineral. 36, 133-55.Google Scholar
Leake, B.E. (1967) Earth Planet. Sci. Lett. 3, 311-16.CrossRefGoogle Scholar
MacPberson, H.G. and Livingstone, A. (1981) Scott. J. Geol. 18, 1-47.CrossRefGoogle Scholar
Mahood, G. and Hildreth, W. (1983) Geochim. Cosmochim. Acta, 47, 11-30.CrossRefGoogle Scholar
Manning, D.A.C. (1983) Mineral. Mag. 47, 353-8.CrossRefGoogle Scholar
Miller, C.F. and Stoddard, E.F. (1981) J. Geol. 89, 233-46.CrossRefGoogle Scholar
Neumann, E.-R. (1974) Am. J. Sci. 274, 107-48.CrossRefGoogle Scholar
Plant, J.A., Brown, G.C., Simpson, P.R., and Smith, R.T. (1980) Trans. Inst. Mining Metall. 92, B198- B210.Google Scholar
Schnetzler, C.C. and Philpotts, J.A. (1970) Geochim. Cosmochim. Acta, 34, 331-40.CrossRefGoogle Scholar
Speer, J.A. (1984) In Micas (Bailey, S.W., ed.) Reviews in Mineralogy, 13, 299-356.CrossRefGoogle Scholar
Stephens, W.E. and Halliday, A.N. (1984) Trans. R. Soc. Edinburgh: Earth Sciences, 75, 259-73.CrossRefGoogle Scholar
Streckeisen, A.L. (1976) Earth Sci. Rev. 12, 1-33.CrossRefGoogle Scholar
Tuttle, O.F. and Bowen, N.L. (1958) Geol. Soc. Am. Mem. 74.Google Scholar
Vennum, W.R. and Meyer, C.E. (1979) Am. Mineral. 64, 268-73.Google Scholar
Weisbrod, A. (1974) Bull. Soc. fr. Mineral. Cristallogr. 97, 261-70.Google Scholar
White, A.J.R. and Chappell, B.W. (1983) Geol. Soc. Am. Memoir, 159, 213-4.Google Scholar
Yardley, B.W.D. (1977) Am. Mineral. 62, 793-80..Google Scholar