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Variations in F and Cl contents in apatites from magnetite—apatite ores in northern chile, and their ore-genetic implications

Published online by Cambridge University Press:  05 July 2018

Peter J. Treloar  and
Howard Colley
Peter J. Treloar
Affiliation:
School of Geological Sciences, Kingston University, Penrhyn Road, Kingston-upon-Thames, Surrey KT1 2EE, UK
Howard Colley
Affiliation:
School of Construction and Earth Sciences, Oxford Brookes University, Gypsy Lane, Oxford OX3 0BP, UK
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Abstract

Magnetite—apatite deposits associated with the Atacama Fault Zone of northern Chile are interpreted here, on field criteria, as being the products either of hydrothermal fluids with a strong magmatic signature, or of late-stage Fe-rich magmas mixed with an aqueous fluid. Even in the Chilean iron belt, apatite-rich magnetite deposits are a rarity. Variations in F- and Cl- contents in apatites, strongly zoned with respect to halogens, are indicative of primary variations in fHF and fHCI in the hydrothermal fluids. Small variations in halogen fugacities in the aqueous fluid are capable of buffering large variations in halogen content within apatite crystals in equilibrium with that fluid. The recorded halogen zonation profiles are inconsistent with crystallization of the apatites simply from a volatile-rich, late-stage fractionation Fe-rich magma, or its derived magmatic vapour. It is more likely that they are the result of mineral—fluid buffering with a fluid that represents the mixing of a magmatically-derived aqueous fluid with a meteoric fluid that has variably scavenged Ca and Cl from within the country rocks. The source magma of the former is probably an Fe-P enriched acidic magma, derived by fractionation of primary calc-alkaline basic magmas.

Keywords

ApatitesChileore-genesishalogen
Type
Halogen Mineralogy and Geochemistry
Information
Mineralogical Magazine , Volume 60 , Issue 399 , April 1996 , pp. 285 - 301
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1996

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References

Atkin, B.P., Injque-Espinoza, J.L. and Harvey, P.K. (1985) In Magmatism at a plate edge: the Peruvian Andes.(W.S. Pitcher et aieds.) Blackie (Glasgow), pp. 261—70.Google Scholar
Baturin, G.N. (1982) Developments in Sedimentology, 33. Elsevier (Amsterdam).Google Scholar
Bell, C.M. (1989) Sedimentology, 36, 651–63.CrossRefGoogle Scholar
Berg, K. and Baumann, A. (1985) Earth. Planet. Sci. Lett., IS, 101 — 15.Google Scholar
Blake, K.L. (1994) Geological Society of America Annual meeting, Seattle, Abstracts with programs.26, no 7, 380.Google Scholar
Bookstrom, A.A. (1977) Econ. GeoL, 72, 1101–30. Bookstrom, A.A. (1995) Econ. Geol, 90, 469–73.CrossRefGoogle Scholar
Boric, R., Diaz, F. and Maksaev, M. (1991) SENAGEOMIN Chile, Boletin 40, 246 pp.Google Scholar
Brenan, J.M. (1993) Earth Planet. Sci. Lett., 117, 251–63.CrossRefGoogle Scholar
Brook, M., Pankhurst, R.J., Shepherd, T.J. and Spiro, B. (1987) British Geological Survey, unpublished report. 190 pp.Google Scholar
Brown, M. (1988) V Congresso Geologico Chileno III, 153–66.Google Scholar
Brown, M., Diaz, F. and Grocott, J. (1993) Geol. Soc. Amer. Bull., 105, 1165–74.2.3.CO;2>CrossRefGoogle Scholar
Buchelt, M. and Cancino, C.T. (1988) In The Southern Central Andes(H. Bahlburg, C. Breitkreuz and P. Giese, eds). Lecture notes in Earth Sciences, Springer-Verlag, Berlin, 17, 171—82.CrossRefGoogle Scholar
Burnham, W., Holloway, J.R. and Davies, N.F. (1969) Geol. Soc. Amer. Sp. Paper, 132, 96pp.Google Scholar
Candela, P.A. (1986) Chem. GeoL, 57, 289–301. Candela, P.A. (1989) Rev. Econ. Geol., 4, 203–21.CrossRefGoogle Scholar
Clark, A.H., Farrar, E., Caelles, J.C., Haynes, S.J., Lortie, R.B., McBride, S.L., Quirt, G.S., Robertson, R.C.R. and Zentilli, M. (1976) Geol. Assoc. Canada Sp. paper, 14, 23–59.Google Scholar
Cliff, R.A., Rickard, D. and Blake, K. (1990) Econ. Geol, 85, 1770–6.CrossRefGoogle Scholar
Colley, H., Treloar, P.J. and Diaz, F. (1989) Econ. Geol. Monograph, 1, 208—17.Google Scholar
Frietsch, R. (1978) Econ. Geol, 73, 478–85.CrossRefGoogle Scholar
Frutos, J. 1982. In Ore genesis: the state of the art.(G.C. Amstutz et aleds) Soc. Geol. Appl Min. Deposits. Spec. Publ. 2, 493—507. Springer-Verlag (Berlin).Google Scholar
Geijer, P. (1960) In Archaean geology of Vasterbotten and Norrbotten, northern Sweden. Guide to excursions A32 and C26. Sweden Geological Survey.Google Scholar
Geijer, P. (1967) Sveriges Geologiska Undersokning. SerC, 624, 32 pp.Google Scholar
Grocott, J., Brown, M., Dallmeyer, R.D., Taylor, G.K. and Treloar, P.J. (1994) Geology, 22, 391–4.2.3.CO;2>CrossRefGoogle Scholar
Guilbert, J.M. and Park, C.F. (1986) The Geology of Ore Deposits. W.H. Freeman & Co. New York. 985 pp.Google Scholar
Henriquez, F., Dobbs, F., Espinoza, S., Nystrom, J., Travisany, V. and Vivallo, W. (1994) 7th Congreso geologica Chileno. 2, 822—4.Google Scholar
Hitzman, M.W., Oreskes, N. and Einaudi, M.T. (1992) Precamb. Res., 58, 241–87.CrossRefGoogle Scholar
Korzhinskiy, M.A. (1981) Geochem Internal, 18, 44–60.Google Scholar
Levi, B., Aguirre, L. and Nystrom, J.O. (1982) Contrib. Mineral. Petrol., 80, 49–58.CrossRefGoogle Scholar
Liou, J.G.S., Kuniyoshi, S. and Ito, T. (1974) Amer. J. ScL, 274, 613–32.CrossRefGoogle Scholar
Mathez, E.A. (1989a) Rev. Econ. Geol.y 4, 21—31.Google Scholar
Mathez, E.A. (198%) Rev. Econ. Geol., 4, 167–79.Google Scholar
Matthews, S.J., Jones, A.P. and Beard, A.D. (1994) J. Geol Soc. Lond., 151, 815–23.CrossRefGoogle Scholar
Naranjo, J.A. (1978) Carta 34. Institute de Investigaciones GeologicasSantiago, Chile.Google Scholar
Nystrom, J.O. and Henriquez, F. (1994) Econ. Geol., 89, 820–39.CrossRefGoogle Scholar
Oreskes, N., Rhodes, A.L., Rainville, K., Sheets, S., Espinoza, S. and Zentilli, M. (1994) Geological Society of America Annual meeting, Seattle, Abstracts with programs. 26, no 7, 379.Google Scholar
Parak, T. (1975) Econ. Geol 70, 1242–58.CrossRefGoogle Scholar
Parak, T. (1984) Econ. Geol 79, 1945–9.CrossRefGoogle Scholar
Park, C.F. (1961) Econ. Geol, 56, 431–6.CrossRefGoogle Scholar
Park, C.F. (1972) Econ. Geol, 67, 339–49CrossRefGoogle Scholar
Pichowiak, S. (1993) In Tectonics of the South Central Andes: structure and evolution of an active continental margin. (Reutter, K-J., Scheuber, E. and Wigger, P.J., eds) Springer–Verlag, Berlin. Pp. 203–17,Google Scholar
Potts, P.J. and Tindle, A.G. (1989) Mineral. Mag., 53, 357–62.CrossRefGoogle Scholar
Ramsay, J.G. and Huber, M,I. (1983) The techniques of modern structural geology. Volume 1, Strain analysis. Academic Press. 307 pp.Google Scholar
Rogers, G. and Hawkesworth, C.J. (1989) Earth Planet. Sci. Lett., 91, 271–85.CrossRefGoogle Scholar
Romer, R.L., Martinsson, O. and Perdahl, J.A. (1994) Econ. Geol., 89, 1249–61.CrossRefGoogle Scholar
Scheuber, E. and Andriessen, P.A.M. (1990) J. Struct. Geol., 12, 243–57.CrossRefGoogle Scholar
Sibson, R.H. (1977) J. Geol. Soc. Land., 133, 191–214.CrossRefGoogle Scholar
Sillitoe, R.H. (1976) Geol. Assoc. Canada. Sp. paper, 14, 59–100.Google Scholar
Tacker, R.C. and Stormer, J.C. (1989) Amer. Mineral, 74, 877–88.Google Scholar
Travisany, V., Henriquez, F. and Nystrom, J.O. (1995) Econ. Geol., 90, 438–44.CrossRefGoogle Scholar
Vidal, C.E. (1985) In Magmatism at a plate edge: the Peruvian Andes.(W.S. Pitcher et al.eds). Blackie (Glasgow) Pp. 243—9.Google Scholar
Whitney, J.A., Hemley, J.J., and Simon, F.O. (1985) Econ. Geol., 80, 444–60.CrossRefGoogle Scholar
Yardley, B.W.D. (1985) Mineral. Mag., 49, 77–80.CrossRefGoogle Scholar
Zhu, C. and Sverjensky, D.A. (1991) Geochim. Cosmochim. Acta, 55, 1837–58.CrossRefGoogle Scholar