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Post-magmatic alteration in eudialyte from the North Qôroq centre, South Greenland

Published online by Cambridge University Press:  05 July 2018

Ian M. Coulson
Ian M. Coulson*
Affiliation:
School of Earth Sciences, The University of Birmingham, Edgbaston, Birmingham B15 2TT, England
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Abstract

The North Qôroq centre comprises a series of nested nepheline syenite intrusions and forms part of the mid-late Proterozoic Gardar province of South Greenland. Within the centre fractionation has produced varied rock types ranging from augite-syenite to lujavrite, a eudialyte microsyenite. Samples of eudialyte from the lujavrites of unit SN1B of the centre show evidence for two-stage alteration. This alteration ranges from slight modification along crystal margins to complete breakdown and replacement by new pseudomorphing phases. Modification to crystal margins is accompanied by increasing Nb and Zr contents and is related to metasomatism produced by the intrusion of younger syenite units of the North Qôroq centre. More extensive alteration is as a result of metasomatism followed by lower-temperature supergene alteration. Simplified reactions for this breakdown include eudialyte + metasomatic fluid = allanite + nepheline; eudialyte + metasomatic fluid = titanite + aegirine + møsandrite + wöhlerite; eudialyte + fluid = zirfesite + fluid. Mass balance calculations for altered compared with unaltered samples of lujavrite show that alteration took place at approximately constant volume with an overall increase in Fe (+2.41 g/100g), Si and K (+0.65 and +0.61 g/100g), whilst Na (−2.67 g/100g) and all trace elements, particularly La, Y, Nb and Zr (−5.6 to −166 g/10000g) are lost from the system.

Keywords

eudialytezirfesitealterationmetasomatismlujavritelgalikoGardarGreenland
Type
Mineralogy
Information
Mineralogical Magazine , Volume 61 , Issue 404 , February 1997 , pp. 99 - 109
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1997

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References

Ahmed, M. and MacKenzie, W.S. (1978) Preliminary report on the synthesis and stability of eudialyte. Progress in Experimental Petrology, Fourth Report 1975-8, 47-9. NERC.Google Scholar
Appleyard, E.C. and Woolley, A.R. (1979) Fenitization: an example of the problems of characterizing mass transfer and volume changes. Chem. Geol., 26, 1–15.CrossRefGoogle Scholar
Appleyard, E.C. (1980) Mass balance computations in metasomatism: Metagabbro/nepheline syenite pegmatite interaction in northern Norway. Contrib. Mineral. Petrol., 73, 131-44.CrossRefGoogle Scholar
Bøggild, O.B. (1953) The mineralogy of Greenland. Medd. øm Grønland, 149;3, 251 pp.Google Scholar
Bollingberg, H.J., Ure, A.M., Sørensen, I. and Leonardsen, E.S. (1983) Geochemistry of some eudialyte-eucolite specimens and a co-existing catapleiite from Langesund, Norway. Tschermaks Min. Petr. Mitt., 32, 153-69.CrossRefGoogle Scholar
Brøgger, W.C. (1890) Die Mineralien der siidnorwegischen Augit-und Nephelin Syenite. Z. Kristallogr., 16, II.Google Scholar
Burt, D.M. (1989) Compositional and phase relations among rare earth element minerals. In Geochemistry and Mineralogy of Rare Earth Elements (Lipin, B.R. and McKay, G.A., eds). Mineralogical Society of America. Reviews in Mineralogy, 21, 259–307.Google Scholar
Coulson, I.M. and Chambers, A.D. (1996) Patterns of zonation in patterns in rare-earth bearing minerals in nepheline syenites of the North Qôroq centre, South Greenland Can. Mineral., 34(6), (in press).Google Scholar
Deer, W.A, Howie, R.A. and Zussman, J. (1986) Rock-Forming Minerals - Volume 1B Disilicates and Ring Silicates (2nd ed.). Longman Scientific & Technical, Harlow, England.Google Scholar
Deer, W.A, Howie, R.A. and Zussman, J. (1992) An Introduction to the Rrock-Forming Minerals (2nd ed.). Longman Scientific & Technical, Harlow, England, 696 pp.Google Scholar
Dorfman, M.D., Ilokhim, V.V. and Burova, T.A. (1963) [Barsanovite – a new mineral.. C. R. Acad. Sci., USSR, 153, 1164-67.(in Russian).Google Scholar
Emeleus, C.H. and Harry, W.T. (1970) The Igaliko Nepheline syenite complex: general description. Medd. øm Grønland, 186;3, 115 pp.Google Scholar
Fryer, B.J. and Edgar, A.D. (1977) Significance of rareearth distributions in coexisting minerals of peralkaline undersaturated rocks. Contrib. Mineral. Petrol., 61, 35–48.CrossRefGoogle Scholar
Gresens, R.L. (1967) Composition-volume relationships of metasomatism. Chem. Geol., 2, 47–55.CrossRefGoogle Scholar
Jones, A.P. and Larsen, L.M. (1985) Geochemistry and REE minerals of nepheline syenites from the Motzfeldt centre, South Greenland. Amer. Mineral., 70, 1087-100.Google Scholar
Jones, A.P., Wall, F. and Williams, C.T. (eds.) (1996) Rare Earth Minerals: Chemistry, Origin and Ore Deposits. The Mineralogical Society Series 7, Chapman and Hall, London, 372 pp.Google Scholar
Khomyakov, A.P. (1990) Mineralogy of Hyperagpaitic Alkaline Roctc∼, Science Press, Moscow, 196 pp (in Russian). Translated into English as Khomyakov, A.P. (1995) Mineralogy of Hyperagpaitic Alkaline Rocks, Clarendon Press, Oxford, 233 pp.Google Scholar
Mellini, M. and Merlino, S. (1979) Refinement of the crystal structure of wöhlerite. Tschermaks Min. Petr. Mitt., 26, 109-23.CrossRefGoogle Scholar
Petersen, O.V., Rønsbo, J.G. and Leonardsen, E.S. (1989) Nacareniobsite-(Ce), a new mineral species from the llímaussaq alkaline complex, South Greenland, and its relation to møsandrite and the rinkite series. Neues Jahrb. Mineral. Mh., 2, 84–96.Google Scholar
Rae, D.A., Coulson, I.M. and Chambers, A.D. (1996) Metasomatism in the North Qôroq centre, South Greenland: apatite chemistry and rare-earth element transport. Mineral. Mag., 60, 207-20.CrossRefGoogle Scholar
Rubie, D.C. (1982) Mass transfer and volume change during alkali metasomatism at Kisingiri, Western Kenya. Lithos, 15, 99–109.CrossRefGoogle Scholar
Rubie, D.C. and Gunter, W.D. (1983) The role of speciation in alkaline igneous fluids during fenite metasomatism. Contrib. Mineral. Petrol., 82, 165-75.CrossRefGoogle Scholar
Sørensen, H. (1962) On the occurrence of steenstrupine in the Ilímaussaq massif, southwest Greenland. Medd. øm Grønland, 32;1, 251 pp.Google Scholar
Upton, B.G.J. and Emeleus, C.H. (1987) Mid Proterozoic alkaline magmatism in southern Greenland. In Alkaline Igneous Rocks (Fitton, J.G. and Upton, B.G.J., eds.). Spec. Publ. Geol. Soc., London, 30, 449–71.Google Scholar
Ussing, N.V. (1911) Geology of the country around Julianehaab. Medd. øm Grønland, 38, 376 pp.Google Scholar
Vlasov, K.A., Kuz'menko, M.Z. and Es'kova, E.M. (1966) The Lovozero Alkali Massif Oliver and Boyd, Edinburgh and London, 627 pp.Google Scholar
Watika, H., Rey, P. and Schmitt, R.A. (1971) Abundances of the 14 rare-earth elements and 12 other trace elements in Apollo 12 samples: five igneous and one breccia rocks and four soils. Proc. 2nd Lunar Sci. Conf., pp. 1319–29.Google Scholar
Walsh, J.N., Buckley, F. and Barker, J. (1981) The simultaneous determination of the rare-earth elements in rocks using inductively coupled plasma source spectrometry. Chem. Geol., 33, 141-53.CrossRefGoogle Scholar