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Relationship between altered pyroxene diorite and the magnetite mineralization in the Chilean Iron Belt, with emphasis on the El Algarrobo iron deposits (Atacama region, Chile)

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Abstract

North of El Algarrobo (one of the four main deposits of the Chilean Iron Belt), the iron-mineralization (magnetite-etrmolite/actinolite-apatite) is related to clinoand orthopyroxene diorite intrusions which have crystallized at shallow depth (4km) under increasing oxygen fugacities. The supercritical fluid phase exsolved during cooling after the consolidation of the plutons (800–900°C), results in a H+, Cl− and sodic enrichment, and in the sequential leaching of Fe (at less than 700°C), then Ca and Mg (between 600 and 500°C) from minerals of the primary magmatic diorite assemblage: titanomagnetite-ilmenite, plagioclase (An70–40), augite, hypersthene. As a consequence of the cationic leaching, the lower mobility of silica and aluminium and the enrichment in sodium, residual altered dioritic rocks present a retromorphic mineral assemblage evolving down to boundary conditions of the greenchist-amphibolite facies (450°C). Fe, Mg and Ca are carried in cationic form associated with Cl− anions, toward cooler rocks where they are precipitated. The deposition (between 550 and 450°C) of magnetite, followed iron-mineralization paragenesis, and occurred in fractured zones located both in altered diorites and contact andesites.

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References

  • Aberg, G., Aguirre, L., Levi, B., Nyström, J. (1984) Spreading-subsidence and generation of ensialic marginal basins: an example from the Early Cretaceous of Central Chile. J. Geol. Soc. London, Spec Issue, 16:185–193

    Google Scholar 

  • Boctor, N.Z., Popp, R.K., Frantz, J.D. (1980) Mineral-solution equilibria-IV. Solubilities and the thermodynamic properties of FeCl2 in the system Fe2O3-H2-H2O-HCl. Geochim. Cosmochim. Acta 44:1509–1518

    Google Scholar 

  • Bookstrom, A.A. (1977) The magnetite deposits of El Romeral. Econ. Geol. 72:1101–1130

    Google Scholar 

  • Braun, E., Raith, M. (1985) Fe-Ti Oxides in metamorphic basites from Eastern Alps, Austria: a contribution to the formation of solid solutions of natural Fe-Ti Oxide assemblage. Contrib. Mineral. Petrol. 90:199–213

    Google Scholar 

  • Burnham, C.W. (1979) Magmas and hydrothermal fluids. In: Barnes, H.L. (ed.) Geochemistry of hydrothermal ore deposits. Wiley, New York, pp71–133

    Google Scholar 

  • Carmichael, I.S.E., Turner, F.J., Verhoogen, J. (1974) Igneous petrology, McGraw Hill, New York, 739 pp

    Google Scholar 

  • Carrasco, P. (1979) Hidrologia de Minas El Algarrobo y su aplicación al drenaje del sector “C” del yacimiento. Unpublished Memoria de Titulo, Univ. de Chile, Santiago, 92 pp

    Google Scholar 

  • Debon, F., Lefort, P. (1984) A chemical-mineralogical classification of common plutonic rocks and association. Trans. Roy. Soc. Edinburgh, Earth Sci. 73:135–149

    Google Scholar 

  • Desborough, G.A. (1963) Mobilization of iron by alteration of magnetite-ulvospinel in basic rocks in Missouri. Econ. Geol. 58:332–346

    Google Scholar 

  • Dymkin, A.M., Purtov, V.K., Yatluk, G.M. (1984) Transport of iron in high-temperature hydrothermal solutions. Int. Geol. Rev. 26: 1180–1184

    Google Scholar 

  • Espinoza, S.R. (1984) Le rôle du volcanisme du Crétacé inférieur dans la métallogenèse de la Ceinture ferrifère d'AtacamaCoquimbo. Unpublished Thèse d'Université, Univ. Paris VI, 153pp

  • Eugster, H.P. (1985) Granites and hydrothermal ore deposits: a framework. Mineral. Mag. 49:7–23

    Google Scholar 

  • Eugster, H.P. (1986) Minerals in hot water. Am. Mineral. 71:655–673

    Google Scholar 

  • Eugster, H.P., Chou I.M. (1979) A model for deposition of Cornwalltype magnetite deposits. Econ. Geol. 74:763–774

    Google Scholar 

  • Frantz, J.D., Popp, R.K. (1979) Mineral-solution equilibria-I. An experimental study of complexing and thermodynamic properties of aqueous MgCl2 in the system MgO-SiO2-H2O-HCl. Geochim. Cosmochim. Acta 43:1223–1239

    Google Scholar 

  • Geijer, P. (1930) The iron ores of Kiruna type. Sveriges Geol. Underso., C, 367, 39 pp

  • Gill, J.B. (1981) Orogenic. andesites and plate tectonics. Springer, Berlin Heidelberg New York, pp390

    Google Scholar 

  • Gresens, R.L. (1967) Composition-volume relationships of metasomatism. Chem. Geol. 2:47–65

    Google Scholar 

  • Haggerty, S.E. (1976) Opaque mineral oxides in terrestrial igneous rocks. Mineral. Soc. Am., Rev. Mineral. 3:Hg101-Hg300

    Google Scholar 

  • Helz, G.R. (1971) Hydrothermal solubility of magnetite. Unpublished Ph.D. thesis, Pennsylvania State Univ. 110pp

  • Hildebrand, R.S. (1986) Kiruna-type deposits: their origin and relationship to intermediate subvolcanic plutons in the Great Bear Magmatic Zone, Northwest Canada. Econ. Geol. 81: 640–659

    Google Scholar 

  • Holland, H.D. (1972) Granites, solutions and base metal deposits. Econ. Geol. 67:281–301

    Google Scholar 

  • Kudo, A.M., Weill, D.F. (1970) An igneous plagioclase thermometer. Contrib. Mineral. Petrol. 25:52–65

    Google Scholar 

  • Kwak, T.A.P., Brown, W.M., Abeysinghe, P.B., Teong, H.T. (1986) Fe solubilities in very saline hydrothermal fluids: their relation to zoning in some ore deposits. Econ. Geol. 81:447–465

    Google Scholar 

  • Liou, J.G., Konioshi, S., Ito, K. (1974) Experimental studies of phase relations between greenschist and amphibolite in basaltic system. Am. J. Sci. 274:613–632

    Google Scholar 

  • Luce, R.W., Cygan, G.L., Hemley, J.J., d'Angelo, W.M. (1985) Some mineral stability relations in the system CaO-MgO-SiO2-H2O-HCl. Geochim. Cosmochim. Acta 49:525–538

    Google Scholar 

  • Ménard, J.J. (1986) Un modèle métasomatique pour les gisements de la Ceinture de fer du Chili. Comptes Rendus, Acad. Sci. 302:775–779

    Google Scholar 

  • Ménard, J.J. (1988) Les relations volcanisme, plutonisme et minéralisation dans la Ceinture de fer du Chili: la région d'El Algarrobo. Unpublished Thèse d'Etat, Univ. Paris XI, 369 pp

  • Ménard J.J. (1990) Ore deposit in the Chilean Iron Belt (Atacama Area, Chile). Intern. Symp. on Andean Geodynamics, Grenoble, pp.313–317

  • Ménard, J.J. (1992) Comparison entre les roches plutoniques associées à la Ceinture de fer du Chili et aux porphyres cuprifères: arguments pétrologiques. Comptes Rendus, Acad. Sci. 315:725–732

    Google Scholar 

  • Miyashiro, A. (1961) Evolution of metamorphic belts. J. Petrol. 2:277–311

    Google Scholar 

  • Montecinos, D.P. (1983) Pétrologie des roches intrusives associées au gisement de fer El Algarrobo (Chili). Unpublished Thèse d'Université, Univ. Paris XI, 191 pp

  • Moody, J.B., Meyer, D., Jenkins, J.E. (1983) Experimental characterization of greenschist-amphibolite boundary in mafic systems. Am. J. Sci. 283:48–92

    Google Scholar 

  • Morton, R.L., Nebel, M.L. (1984) Hydrothermal alteration of felsic volcanic rocks at the Helen Siderite deposit, Wawa, Ontario. Econ. Geol. 79:1319–1333

    Google Scholar 

  • Mpodozis C., Allmendinger R. (1992) Extension cretácica a gran escala en el Norte de Chile (Puquios-Sierra Fraga, 27°S): significado para la evolución tectónica de los Andes. Rev. Geol. Chile 19:167–197

    Google Scholar 

  • Munizaga, F., Huete, C., Hervé, F. (1985) Geocronologia K-Ar y Razones Iniciales Sr87/Sr86 de la “Faja Pacifica” de “Desarrollos Hidrotermales”. IVto Congreso Geológico Chileno, Antofagasta, 4:357–379

    Google Scholar 

  • Nortorn, D., Cathles, L.M. (1979) Thermal aspects of the ore deposition. In: Barnes, H.L. (ed.) Geochemistry of hydrothermal ore deposits. Wiley, New York, pp. 611–631

    Google Scholar 

  • Oyarzun, J. (1985) La Métallogénie Andine: cadre géologique, pétrologique et géochimique et essai d'interprétation. Unpublished Thèse d'Etat, Univ. Paris XI, 864 pp

  • Park, C.F. (1972) The iron ore deposits of the Pacific Basin. Econ. Geol. 67:339–349

    Google Scholar 

  • Philpotts, A.R. (1967) Origin of certain iron-titanium oxide and apatite rocks. Econ. Geol. 62:303–315

    Google Scholar 

  • Philpotts, A.R., Doyle, C.D. (1983) Effect of magma oxidation state on the extent of silica liquid immiscibility in the tholeiitic basalt. Am. J. Sci. 283:967–986

    Google Scholar 

  • Pichon, R. (1981) Contribution à l'étude de la Ceinture de fer du Chili. Les gisements de Bandurrias (Prov. d'Atacama) et de Los Colorados Norte (Prov. de Huasco). Unpublished Thèse 3ème cycle, Univ. Paris XI, 326 pp

  • Popp, R.K., Frantz, J.D. (1979) Mineral-solution equilibria-II. An experimental study of mineral solubilities and thermodynamic properties of aqueous CaCl2 in the system CaO-SiO2-H2O-HCl. Geochim. Cosmochim. Acta 43:1777–1790

    Google Scholar 

  • Popp, R.K., Frantz, J.D. (1980) Mineral-solution equilibria-III. The system Na2O-Al2O3-SiO2-H2O-HCl. Geochim. Cosmochim. Acta 44:1029–1037

    Google Scholar 

  • Ripley, E.M., Ohmoto, H. (1979) Oxygen and hydrogen isotopic studies of ore deposition and metamorphism at Raul mine, Peru. Geochim. Cosmochim. Acta 42:1633–1643

    Google Scholar 

  • Ruiz, C., Aguirre, L., Corvalan, J., Klohn, C., Klohn, E., Levi, B. (1965) Geologia y yacimientos metaliferos de Chile. Instit. Investig. Geol., Santiago de Chile, 305 pp

    Google Scholar 

  • Ruiz, C., Ortiz, F., Moraga, A., Aguilar, A. (1968) Genesis of the Chilean iron ore deposits of Mesozoic age. XXIIIth Intern. Geol. Congr., Pragua, 7:328–336

    Google Scholar 

  • Spencer, K.S., Lindslay, D.H. (1981) A solution model for coexisting iron-titanium oxides. Am. Mineral. 66:1189–1201

    Google Scholar 

  • Stern, C., Elthon, D. (1979) Vertical variations in the effects of hydrothermal metamorphism in the Chilean ophiolites: their implications for ocean floor metamorphism. Tectonophysics 55:179–213

    Google Scholar 

  • Wells, P.R.A. (1977) Pyroxene thermometry in simple and complex system. Contrib. Mineral. Petrol. 62:129–139

    Google Scholar 

  • Whitney, J.A., Hemley, J.J., Simon, F.O. (1985) The concentration of iron in chloride solutions equilibrated with granitic compositions: the sulphur-free system. Econ. Geol. 80:444–460

    Google Scholar 

  • Wood, B.J., Banno, S. (1973) Garnet-orthopyroxene and orthopyroxene-clinopyroxene relationships in the simple and complex systems. Contrib. Mineral. Petrol. 42:109–124

    Google Scholar 

  • Zentilli, M. (1974) Geological evolution and metalogenic relationship in the Andes of Northern Chile between 26° and 29°S. Unpublished Ph.D. thesis, Queens Univ., Kingston, Ontario, 394pp

    Google Scholar 

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  1. J. -J. Ménard

    Present address: Laboratoire de Pétrographie-Volcanologie, Bâtiment 504, F-91405, Orsay Cedex, France

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  1. Département des Sciences de la Terre, Faculté des Sciences, Université de Yaounde I, B.P. 812, Yaounde, Cameroun

    J. -J. Ménard

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Ménard, J.J. Relationship between altered pyroxene diorite and the magnetite mineralization in the Chilean Iron Belt, with emphasis on the El Algarrobo iron deposits (Atacama region, Chile). Mineral. Deposita 30, 268–274 (1995). https://doi.org/10.1007/BF00196362

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