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Aluminium phosphate mineralization from the hypogene La Vanguardia kaolin deposit (Chile)

Published online by Cambridge University Press:  09 July 2018

H. G. Dill ,
A. Fricke ,
K.-H. Henning  and
C. H. Theune
H. G. Dill
Affiliation:
Bundesanstalt für Geowissenschaften und Rohstoffe, PO Box 51 O153, D-30631 Hannover, Germany
A. Fricke
Affiliation:
Ernst-Moritz-A rndt- University, GreifswaldEarth Science Section, F. L.-Jahnstr. 17a, D-17489, GreifswaldGermany
K.-H. Henning
Affiliation:
Ernst-Moritz-A rndt- University, GreifswaldEarth Science Section, F. L.-Jahnstr. 17a, D-17489, GreifswaldGermany
C. H. Theune
Affiliation:
EPROM Ltda., PO Box 17219, Av. Providencia 2133 Of. 207, SantiagoChile
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Abstract

In the region of Illapel, Chile, dioritic and andesitic rocks of Cretaceous to Paleocene age from the Unidad San Lorenzo Formation have suffered strong alteration resulting in the formation of a kaolin-rich zone, which is mined in the La Vanguardia open pit near Combarbalá. Detailed mineralogical and chemical investigations of channel samples from this mine, involving a combination of optical microscopy, XRD, SEM-EDX, XRF and TEM, permitted recognition of a zone of silicification and a zone of advanced argillic alteration, both of which contain alunite s.s. and aluminium-phosphate-sulphate (APS) minerals of the woodhouseite group with subordinate amounts of gorceixite, florencite and goyazite. These minerals are found to have originated from infiltration of meteoric waters. The passage from silicification into advanced argillic alteration was associated with an increase in sulphate activity as manifested by the increase of SO42— at the expense of PO43— in the alunite s.s. and by an increase of the Au content from 0.01 to 0.03 mg/kg Au. This high sulphidation type of wallrock alteration may be roughly compared with the Nansatu type of White (1991).

Type
Research Article
Information
Clay Minerals , Volume 30 , Issue 3 , September 1995 , pp. 249 - 256
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1995

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References

Alpers, C.N. & Brimhall, G.H. (1988) Middle Miocene climatic changes in the Atacama Desert, northern Chile: Evidence from supergene mineralization at La Escondida. Geol. Soc. America Bull. 100, 1640–1656.Google Scholar
Aokf, M. (1991) Mineralogical features and genesis of alunite solid solution in high temperature magmatic hydrothermal systems. Geol. Surv. Japan Rep. 277, 35–37.Google Scholar
Beane, R.E. & Titley, S.R. (1981) Porphyry copper deposits. II. Hydrothermal alteration and mineralization. Econ. Geol. 75th Anniv. Vol. 235–269.Google Scholar
Buchanan, L. (1981) Precious metal deposits associated with volcanic environments in the Southwest. Ariz. Geol. Soc. Dig. 14, 237–262.Google Scholar
Cecioni, A.J. & Dick, L.A. (1992) Geologia del yacimiento epitermal de oro y plata Can Can, Franja de Macunga, Precordillera de Copiapo, Chile. Revista Geoldgica de Chile. 19, 3–17.Google Scholar
Davidson, J. & Mpodozis, C. (1991) Regional geological setting of epithermal gold deposits Chile. Econ. Geol. 186, 1171–1186.Google Scholar
Dill, H.G., Busch, K. & Blum, N. (1991) Chemistry and origin of veinlike phosphate mineralization, Nuba Mts. (Sudan). Ore Geol. Rev. 6, 9–24.Google Scholar
Hayba, D.O., Bethke, P.M., Healo, P. & Foley, N.K. (1985) Geologic, mineralogic and geochemical characteristics of volcanic-hosted epithermal precious-metal deposits. Rev. Econ. Geol. 2, 129—167.Google Scholar
LI, G., Peacor, D.R., Essene, E.J., Broshnahan, D.R. & Beane, R.E. (1992) Walthierite, Ba0.5Al3-(SO4)2(OH)6, and huangite Ca0.5A13(SO4)2(OH)6, two new minerals of the alunite group from the Coquimbo region, Chile. Am. Miner. 77, 1275–1284.Google Scholar
Maksimovic, Z. & Pantó, Gy. (1985) Neodymian goyazite in the bauxite deposit of Vlasenica, Yugoslavia. Tschermaks Min. Petr. Mitt. 34, 159–165.Google Scholar
Müller, G. (1967) Methods in sedimentary petrology. 283 pp, Schweizerbart, Stuttgart, Germany.Google Scholar
Oyarzun, J.M. (1990) The metalliferous ore deposits of Chile and Argentina, and their geologic framework. Pp. 61—78 in: Stratabound Ore Deposits in the Andes, (Fontboté, L., Amstutz, H.C., Cardozo, M., Cedillo, E. & Fmtos, S., editors). Springer, Berlin, Germany.Google Scholar
Rivano, G.S. & Sepulveda, H.P. (1991) Carta Geologica de Chile Hoja Illapel — escala 1:250 000, 107 pp., Serv. Nac. de Geologia y Mineria, Santiago.Google Scholar
Scott, K.M. (1987) Solid solution in, and classification of, gossan-derived members of the alunite-jarosite family, Northwest Queensland, Australia. Am. Miner. 72, 178–187.Google Scholar
SERVICIO NACIONAL DE GEOLOGIA Y MINERIA (1992) Mapa Geologico de Chile escala 1:1 000 000 Hoja No. 30°34'-37°10', Lat. S.Google Scholar
Sillitoe, R.H. (1991) Gold metallogeny of Chile — an introduction. Econ. Geol. 81, 1987–1205.Google Scholar
Spotfl, C. (1990) Authigenic aluminium phosphate - sulphates in sandstones of the Mitterberg Formation, Northern Calcareous Alps., Austria. Sedimentology, 37, 837–845.Google Scholar
Stiörr, M., Köster, H., Kromer, H. & Hilz, M. (1991) Minerale der Crandallit-Reihe im Kaolin von Hirschau-Schnaittenbach, Oberpfalz. Z. geol. Wiss. 19, 677–683.Google Scholar
Stoffregen, R.E. & Alpers, C.N (1987) Woodhouseite and svanbergite in hydrotherm.al ore deposits: products of apatite destruction during advanced argillic alteration. Can. Miner. 25, 201–211.Google Scholar
Stoffregen, R.E & Cygan, G.L. (1989) An experimental study of Na-K exchange between alunite and aqueous sulfate solution. Am. Miner. 75, 209—220.Google Scholar
Streckeisen, A. (1966) Classification and nomenclature of igneous rocks. N. Jb. Mineralogie Abh. 107, 144–240.Google Scholar
Tabak, B.M. (1968) Kaolin deposits of Chile. XXII Int. Geol. Congr. 1968. 16, 89–96.Google Scholar
vila, T. & Sill1Toe, R.H. (1991) Gold-rich porphyry systems in the Maricunga Belt, Northern Chile. Econ. Geol. 86, 1238–1260.Google Scholar
White, N.C. (1991) High sulfidation epithermal gold deposits: Characteristics and a model for their origin. Geol. Surv. Japan Rep. 277, 9–20.Google Scholar