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Nb-rich baotite in carbonatites and fenites at Haast River, New Zealand

Published online by Cambridge University Press:  05 July 2018

Alan F. Cooper
Alan F. Cooper*
Affiliation:
Geology Department, University of Otago, P.O. Box 56, Dunedin, New Zealand
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Abstract

Baotite occurs as an accessory mineral in carbonatites, fenites, and carbothermal veins associated with a lamprophyre dyke swarm in the Haast River area of south Westland, New Zealand. Carbonatites are petrogenetically evolved, with assemblages dominated by ankerite, siderite and Ba-Sr-REE carbonates. Microprobe analysis indicates baotite compositions more Nb-rich than previously recorded, with compositions close to Ba4[Ti3(Nb,Fe)5]Si4O28Cl. Ti must be partially replaced in both crystallographically-independent octahedral sites. Compositional zoning, and stoichiometric considerations suggest that the dominant octahedral substitution is the same as that described in rutile, namely 3Ti4+ ⇌ 2Nb5+ + Fe2+. Contrary to previous suggestions, Fe in the octahedral site should, therefore, be dominated by Fe2+.

The presence of baotite further documents the involvement of halogens in carbonatite magmas. In the New Zealand occurrences it is suggested that the chlorine originates from associated phonolitic magmas and is partitioned into carbonatite during liquid immiscibility.

Keywords

baotitecarbonatitefeniteNew Zealand
Type
Mineralogy
Information
Mineralogical Magazine , Volume 60 , Issue 400 , June 1996 , pp. 473 - 482
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1996

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References

Andersen, T. (1986) Magmatic fluids in the Fen carbonatite complex, S.E. Norway. Evidence of mid-crustal fractionation from solid and fluid inclusions in apatite. Contrib. Mineral. Petrol., 93, 491–503.CrossRefGoogle Scholar
Barreiro, B.A. and Cooper, A.F. (1987) A Sr, Nd, and Pb isotope study of alkaline lamprophyres and related rocks from Westland and Otago, South Island, New Zealand. Geol. Soc. Amer. Spec. Pap., 215, 115–25.Google Scholar
Benoit, P.H. (1987) Adaption to microcomputer of the Appleman-Evans program for indexing and least square refinement of powder-diffraction data for unit-cell dimensions. Amer. Mineral, 72, 1018–9.Google Scholar
Černý, P., Cech, F. and Povondra, P. (1964) Review of ilmenorutile-struverite minerals. Neues Jahrb. Mineral., AbK 101, 142–72.Google Scholar
Cooper, A.F. (1971) Carbonatites and fenitization associated with a lamprophyric dyke-swarm intrusive into schists of the New Zealand Geosyncline. Bull. Geol Soc. Amer., 82, 1327–40.CrossRefGoogle Scholar
Cooper, A.F. (1979) Petrology of ocellar lamprophyres from Western Otago, New Zealand. J. Petrol, 20, 139–63.CrossRefGoogle Scholar
Cooper, A.F. (1983) Mineralogy and geochemistry of a barian carbonatite and associated ultrasodic fenites from a lamprophyre dyke swarm, south Westland, New Zealand. Geol. Soc. Australia Abstract Series, 9, 291–2.Google Scholar
Cooper, A.F. (1986) A carbonatitic lamprophyre dyke swarm from the Southern Alps, Otago and Westland, New Zealand. Bull. Roy. Soc. New Zealand, 23, 313–36.Google Scholar
Cooper, A.F., Barreiro, B.A., Kimbrough, D.L. and Mattinson, J.M. (1987) Lamprophyre dyke intrusion and the age of the Alpine Fault, New Zealand. Geology, 15, 941–4.2.0.CO;2>CrossRefGoogle Scholar
Cooper, A.F., Paterson, L.A. and Reid, D.L. (1995) Li in carbonatites - consequence of an enriched mantle source? Mineral Mag., 59, 401–8.CrossRefGoogle Scholar
Currie, K.L. and Ferguson, J. (1971) A study of fenitization around the alkaline carbonatite complex at Callender Bay, Ontario, Canada. Canad. J. Earth Set, 8, 498–517.CrossRefGoogle Scholar
Dawson, J.B. (1989) Sodium carbonatite extrusions from Oldoinyo Lengai, Tanzania: implications for carbonatite complex genesis. In Carbonatites: Genesis and evolution (K. Bell, ed.) 225—77. Unwin-Hyman, London.Google Scholar
Dawson, J.B., Pinkerton, H., Pyle, D.M. and Nyamweru, C. (1994) June 1993 eruption of Oldoinyo Lengai, Tanzania: Exceptionally viscous and large carbonatite lava flows and evidence for coexisting silicate and carbonate magmas. Geology, 22, 799—802.Google Scholar
Efimov, A.F. and Es'kova, E.M. (1973) New data on geology, mineralogy and geochemistry of alkaline rocks. Moscow (In Russian).Google Scholar
Freestone, I.C. and Hamilton, D. L. (1980) The role of liquid immiscibility in the genesis of carbonatites an experimental study. Contrib. Mineral. Petrol., 73, 105—17.CrossRefGoogle Scholar
Gittins, J. (1989) The origin and evolution of carbonatite magmas. In Carbonatites: Genesis and evolution (Bell, K., ed.) 580—600. Unwin-Hyman, London.Google Scholar
Goldschmidt, V.M. (1954) Geochemistry. Oxford University Press, London.Google Scholar
Heinrich, E.W., Boyer, W.H. and Crowley, F.A. (1962) Baotite (Pao-T’ou-K’uang) from Ravalli County, Montana. Amer. Mineral, 41, 987—93.Google Scholar
Hogarth, D.D. (1989) Pyrochlore, apatite and amphi- bole: distinctive minerals in carbonatite. In Carbonatites: Genesis and evolution (Bell, K., ed.) 105—48. Unwin-Hyman, London.Google Scholar
Jago, B.C. and Gittins, J. (1991) The role of fluorine in carbonatite magma evolution. Nature, 349, 56–8.CrossRefGoogle Scholar
Johan, Z., Johan, V. and Besson, M. (1991) Tungstenbearing baotite from Pierrefitte, Pyrenees, France. Mineral. Petrol, 45, 19–27.CrossRefGoogle Scholar
Keller, J. and Kraft, M. (1989) Composition of natrocarbonatite lavas, Oldoinyo Lengai 1988. Terra Abstracts 1, 286.Google Scholar
Nekrasov, Y.V., Ponomarev, V.I., Simonov, V.I. and Kheiker, D.M. (1970) Refinement of the atomic structure of baotite and the isomorphic relationships in this mineral. Soviet Physics Crystallography, 14, 508–14.Google Scholar
Nemec, D. (1987) Baotite — a rock-forming mineral of Ba-rich hyperpotassic dyke rocks. Neues Jahrb. Mineral, Mh., 31—42.Google Scholar
Nesbitt, B.E. and Kelly, W.C. (1977) Magmatic and hydrothermal inclusions in carbonatite of the Magnet Cove Complex, Arkansas. Contrib. Mineral. Petrol., 63, 271–94.CrossRefGoogle Scholar
Paterson, L.A. (1992) A study of carbonatites and associated fenitisation at Haast River,south Westland, New Zealand PhD thesis, University of Otago Library, 440pp.Google Scholar
Peng, Ch'i-Jui. (1959) The discovery of several new minerals of rare elements, Ti-chih K'o-hsueh, 10, 289 (In Chinese) (Amer. Mineral., 45, 754).Google Scholar
P'eng, Chih-chung and Kuang-jung, Chang. (1963) The crystal structure of baotite. Scientia Sinica, 12, 101 — 19 (In Russian) (M.A. 16, 610).Google Scholar
Peterson, T.D. (1990) Petrology and genesis of natrocarbonatite, Contrib. Mineral. Petrol, 105, 143–55.CrossRefGoogle Scholar
Rankin, A.H. (1977) Fluid-inclusion evidence for the formation conditions of apatite from the Tororo carbonatite complex of eastern Uganda. Mineral. Mag., 41, 155–64.CrossRefGoogle Scholar
Semenov, E.I. Ven-Sin, K. and Kapitonova, T.A. (1961) Baotite, a new niobium mineral. Comptes Rendus Akademiia Science USSR, 136, 915–6.(M.A.15, 135).Google Scholar
Shuriga, T.N. Piabeva, H.G. and Dubakina, L.S. (1980) Baotite, a new find in the USSR. Dokl. Akad. Nauk SSSR, 252, 1220–3.Google Scholar
Simonov, V.I. (1960) Baotite — a mineral with [Si4Oi2] metasilicate rings. Soviet Physics-Crystallography, 5, 523–5.Google Scholar
Sweatman, T.R. and Long, J.V.P. (1969) Quantitative electron-probe microanalysis of rock-forming minerals. J. Petrol, 10, 332–79.CrossRefGoogle Scholar
Wilson, A.D. (1955) A new method for the determination of ferrous iron in rocks and minerals. Bull. Geol. Surv. Gt. Britain, 9, 56—8.Google Scholar
Woolley, A.R. (1969) Some aspects of fenitisation with particular reference to Chilwa Island and Kangankunde, Malawi. Bull. Brit. Mus. Nat. Hist. (Mineral.), 191-219.Google Scholar