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Supergene Origin of the Lastarria Kaolin Deposit, South-Central Chile, and Paleoclimatic Implications

Published online by Cambridge University Press:  28 February 2024

H. A. Gilg
Affiliation:
Lehrstuhl für Angewandte Mineralogie und Geochemie, Technische Universität München, Lichtenbergstr, 4, 85747 Garching, Germany
S. Hülmeyer
Affiliation:
Institut für Allgemeine und Angewandte Geologie, Ludwig-Maximilians-Universität München, Luisenstr. 37, 80333 München, Germany
H. Miller
Affiliation:
Institut für Allgemeine und Angewandte Geologie, Ludwig-Maximilians-Universität München, Luisenstr. 37, 80333 München, Germany
S. M. F. Sheppard
Affiliation:
Laboratoire de Science de la Terre and CNRS-UMR 5570, Ecole Normale Supérieure de Lyon, 46 Allée d'Italie, 69364 Lyon, France

Abstract

The residual kaolin deposits near Lastarria, South-Central Chile, were formed by weathering of subvolcanic quartz porphyry stocks, which intruded the metamorphic basement of the Coastal Cordillera. The clay fractions (<2 µm) consist mainly of poorly-ordered, very fine-grained kaolinite and lath-shaped illite (17–38 wt. %) with minor amounts of quartz, sanidine, and goethite. A sample from the top of the deposit contains major quantities of gibbsite morphologically indistinguishable from kaolinite flakes. The gibbsite-free clays contain 35.5–36.6 wt. % Al2O3, 0.4–2.6 wt. % Fe2O3, 1.3–3.9 wt. % K2O, and have low TiO2 concentrations (<0.02 wt. %). The absence of quartz veining, the abundance of melt inclusions, and the scarcity of secondary fluid inclusions in quartz phenocrysts from altered rocks imply a lack of significant hydrothermal activity in the quartz porphyries. The δ 18O and δD values of the kaolins indicate formation in a weathering environment at significantly higher annual mean air temperatures (∼12°C) than present mean temperatures of ∼9.4°C. Uplift of the region alone probably cannot account for the change in climate. The stable isotope composition of gibbsite is consistent with an origin of desilication of kaolinite at superficial temperatures. Various criteria proposed to distinguish supergene from hypogene kaolins are discussed.

Type
Research Article
Copyright
Copyright © 1999, The Clay Minerals Society

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References

Alderton, D.H.M. and Rankin, A.K., 1983 The character and evolution of hydrothermal fluids associated with the kaolinized St. Austell granite, SW England Journal of the Geological Society (London) 140 297309 10.1144/gsjgs.140.2.0297.CrossRefGoogle Scholar
Arribas, A. Jr. Cunningham, C.G. Rytuba, J.J. Rye, R.O. Kelly, W.C. Podwysocki, M.H. McKee, E.H. and Tosdal, R.M., 1995 Geology, geochronology, fluid inclusions and isotope geochemistry of the Rodalquilar gold alunite deposit, Spain Economic Geology 90 795822 10.2113/gsecongeo.90.4.795.CrossRefGoogle Scholar
Bigeleisen, J. Perlman, M.L. and Presser, H.C., 1952 Conversion of hydrogenic materials to hydrogen for isotopic analysis Analytical Chemistry 24 13561357 10.1021/ac60068a025.CrossRefGoogle Scholar
Bird, M.I. Chivas, A.R. and Andrew, A.S., 1989 A stableisotope study of lateritic bauxites Geochimica et Cosmochimica Acta 53 14111420 10.1016/0016-7037(89)90073-2.CrossRefGoogle Scholar
Bird, M.I. Longstaffe, F.J. Fyfe, W.S. Tazaki, K. and Chivas, A.R., 1994 Oxygen-isotope fractionation in gibbsite: synthesis experiments versus natural samples Geochimica et Cosmochimica Acta 58 52675277 10.1016/0016-7037(94)90310-7.CrossRefGoogle Scholar
Bray, C.J. and Spooner, E.T.C., 1983 Sheeted vein Sn-W mineralization and greisenization associated with economic kaolinization, Goonbarrow china clay pit, St. Austell, Cornwall, England: geologic relationships and geochronology Economic Geology 78 10641089 10.2113/gsecongeo.78.6.1064.CrossRefGoogle Scholar
Bristow, C.M., 1977 A review of the evidence for the origin of the kaolin deposits in S.W. England Proceedings of 8th International Kaolin Symposium and Meeting on Alunite .Google Scholar
Chen, C.-H. Liu, K.-K. and Shieh, Y.-N., 1988 Geochemical and isotopic studies of bauxitization in the Tatun volcanic area, northern Taiwan Chemical Geology 68 4156 10.1016/0009-2541(88)90085-X.CrossRefGoogle Scholar
Clayton, R.N. and Mayeda, T.D., 1963 The use of bromine pentafluoride in the extraction of oxygen from oxides and silicates for analysis Geochimica et Cosmochimica Acta 27 4352 10.1016/0016-7037(63)90071-1.CrossRefGoogle Scholar
Cravero, F. Domínguez, E. and Murray, H.H., 1991 Valores δ18O y δD en caolinitas indicatores de un clima templado-humedo para el Jurásico superior-Cretácio inferior de la Patagonia Revista de la Asociacion Geologica Argentina 46 2025.Google Scholar
Crowley, T.J. and North, G.R., 1991 Paleoclimatology New York Oxford University Press 183211.Google Scholar
Dansgaard, W., 1964 Stable isotopes in preciptiation Tellus 16 436468 10.3402/tellusa.v16i4.8993.CrossRefGoogle Scholar
Dill, H.G. Bosse, H.-R. Henning, K.-H. Fricke, A. and Ahrendt, H., 1997 Mineralogical and chemical variations in hypogene and supergene kaolin deposits in a mobile fold belt of the Central Andes of northwestern Peru Mineralium Deposita 32 149163 10.1007/s001260050081.CrossRefGoogle Scholar
Domínguez, E., 1990 δl8O‰, δ34S ‰, δD ‰ en pirita y caolinita como indicatores de procesos hidrotermales mag-máticos en Andacollo, Neuquén. (nota breve) Revista de la Asociacion Geologica Argentina 45 403406.Google Scholar
Domfnguez, E. Murray, H.H., Churchmann, G.J. Fitzpatrick, R.W. and Eggleton, R.A., 1995 Genesis of the Chubut river valley kaolin deposits, Argentina, and their industrial applications Clays Controlling the Environment Melbourne CSIRO Publishing 129134.Google Scholar
Fontes, J.C., Fritz, P. and Fontes, J.C., 1980 Environmental isotopes in groundwater hydrology Handbook of Environmental Isotope Geochemistry, Volume I Amsterdam Elsevier 179226.Google Scholar
Gilg, H.A. and Sheppard, S.M.E., 1996 Hydrogen isotope fractionation between kaolinite and water revisited Geochimica et Cosmochimica Acta 60 529533 10.1016/0016-7037(95)00417-3.CrossRefGoogle Scholar
Hayase, K., 1969 Génesis del yacimiento de caolíh de la mina “Villegas”, provincia de Chubut, República Argentina Revista de la Associacion Geologica Argentina 24 5571.Google Scholar
Hedenquist, J.W. Izawa, E. Arribas, A. and White, N.C., 1996 Epithermal gold deposits: styles, characteristics and exploration Journal of the Society of Resource Geology Special Publication 1 116.Google Scholar
Hervé, F. Pankhurst, RJ B M Alfaro, G. Frutos, J. Miller, H. Schira, W. Amstutz, C., Fontboté, L. Amstutz, G.C. Cardozo, M. Cedillo, E. and Frutos, J., 1990 Rb-Sr and Sm-Nd data from some massive sulfide occurrences in the metamorphic basement of South-Central Chile Strata-bound Ore Deposits in the Andes Berlin Springer Verlag 221228 10.1007/978-3-642-88282-1_16.CrossRefGoogle Scholar
Heyer, E., 1993 Witterung und Klima. B.G. Teubner Leipzig 10.1007/978-3-322-83746-2.CrossRefGoogle Scholar
Hufmann, L. Miller, H. and Alfaro, G., 1997 Ophiolithabfolge in der südchilenischen Küstenkordillere mit Backarc Beckensignatur Berichte der Deutschen Mineralogischen Gesellschaft, Supplement to European Journal of Mineralogy 9 166.Google Scholar
Hufmann, L. Miller, H. and Alfaro, G., 1997 Ocean floor magmatic rocks within the accretionary belt of Cerros de Maulén area, Coastal Range, IX. región, Chile. VIII Congreso Geologico Chileno Antofagasta Actas 3 16501655.Google Scholar
IAEA/WMO., 1994 Global Network for Isotopes in Precipitation (GNIP) Database .Google Scholar
Imguez Rodriguez, A.M., 1982 Basaltic and rhyolitic rocks as parent materials of halloysite in Argentine deposits Developments in Sedimentology 35 605612.Google Scholar
Keller, W.D. and Heller, L., 1969 Classification and problems of hydro-thermal refractory clay deposits in Mexico Proceedings of the International Clay Conference, Tokyo, Volume 1 305312.Google Scholar
Keller, W.D. and Heller, L., 1970 Discussion of J. Konta: Comparison of the proofs of hydrothermal and supergene kaolinization in two areas of Europe Proceedings of the International Clay Conference, Tokyo, Volume 2 9193.Google Scholar
Keller, W.D., 1976 Scan electron micrographs of kaolins collected from diverse environments of origin—I Clays and Clay Minerals 24 107113 10.1346/CCMN.1976.0240301.CrossRefGoogle Scholar
Keller, W.D., 1976 Scan electron micrographs of kaolins collected from diverse environments of origin—II Clays and Clay Minerals 24 114117 10.1346/CCMN.1976.0240302.CrossRefGoogle Scholar
Keller, W.D., 1978 Scan electron micrographs of the kaolinization process including examples from the Bohemian Massif Schriftenreihe fuer Geologische Wissenschaften, Berlin 11 89108.Google Scholar
Kitagawa, R. and Köster, H.M., 1991 Genesis of the Tirschenreuth kaolin deposit in Germany compared with the Kohdachi kaolin deposit in Japan Clay Minerals 26 6179 10.1180/claymin.1991.026.1.07.CrossRefGoogle Scholar
Konta, J. and Heller, L., 1969 Comparison of the proofs of hydrothermal and supergene kaolinzation in two areas of Europe Proceedings of the International Clay Conference, Tokyo, Volume 1 281290.Google Scholar
Konta, J. and Heller, L., 1970 Discussion of J. Konta: Comparison of the proofs of hydrothermal and supergene kaolinization in two areas of Europe Proceedings of the International Conference, Tokyo, Volume 2 9193.Google Scholar
Köster, H.M. and Heller, L., 1969 Beitrag zu Geochemie der Kaoline Proceedings of the International Clay Conference, Tokyo, Volume I 273280.Google Scholar
Lawrence, J.R. and Taylor, H.P., 1971 Deuterium and oxygen-18 correlation: Clay minerals and hydroxides in Quaternary soil compared to meteoric waters Geochimica et Cosmochimica Acta 35 9931003 10.1016/0016-7037(71)90017-2.CrossRefGoogle Scholar
Lombardi, G. and Sheppard, S.M.F., 1977 Petrographic and isotopic studies of the altered acid volcanics of the Tolfa-Cerite area, Italy: The genesis of the clays Clay Minerals 12 147162 10.1180/claymin.1977.012.02.05.CrossRefGoogle Scholar
MacKenzie, R.C., 1957 The Differential Thermal Analysis of Clays London Mineralogical Society.Google Scholar
Manning, D.A.C., 1995 Introduction to Industrial Minerals London Chapman & Hall 10.1007/978-94-011-1242-0.CrossRefGoogle Scholar
Marumo, K., 1989 Genesis of kaolin minerals and pyrophyllite in Kuroko deposits of Japan: Implications for the origin of the hydrothermal fluids from mineralogical and stable isotope data Geochimica et Cosmochimica Acta 53 29152924 10.1016/0016-7037(89)90168-3.CrossRefGoogle Scholar
Marumo, K. Matsuhisa, Y. and Nagasawa, K., 1982 Hydrogen and oxygen isotopic composition of kaolin minerals in Japan Developments in Sedimentology 35 315320.Google Scholar
Meyer, C. Hemley, J.J. and Barnes, H.L., 1967 Wall rock alteration Geochemistry of Hydrothermal Ore Deposits New York Holt, Rinehart and Winston 166235.Google Scholar
Muñoz, J. Duhart, P. Crignola, P. Farmer, G.L. and Stern, C., 1997 The mid-Tertiary coastal magmatic belt, South-Central Chile VIII Congreso Geologico Chileno Antofagasta Actas 3 16941698.Google Scholar
Murray, H.H. and Bailey, S.W., 1988 Kaolin minerals: Their genesis and occurrences Hydrous phyllosilicates (Reviews in Mineralogy, Volume 19) Washington, DC. Mineralogical Society of America 6789 10.1515/9781501508998-009.CrossRefGoogle Scholar
Murray, H.H. Keller, W.D., Murray, H.H. Bundy, W. and Harvey, C., 1993 Kaolins, kaolins and kaolins Kaolin Genesis and Utilization Boulder, Colorado The Clay Mineral Society 124.CrossRefGoogle Scholar
Nicolas, J., 1958 Sur la genèse des kaolins de Guiscriff (Finistère) Clay Minerals Bulletin 3 244248 10.1180/claymin.1958.003.19.07.CrossRefGoogle Scholar
Parrish, J. Ziegler, A. and Scotese, C., 1982 Rainfall patterns and the distribution of coals and evaporites in the Mesozoic and Cenozoic Paleogeography Paleoclimatology and Paleoecology 40 67101 10.1016/0031-0182(82)90085-2.CrossRefGoogle Scholar
Reyes, A.G., 1991 Mineralogy, distribution and origin of acid alteration in Philippine geothermal systems Geological Survey of Japan, Special Report: Chishitsu Chosasho Tokubetsu Hokoku 277 5966.Google Scholar
Romero, A.J.B. Domínguez, E. and Whewell, R., 1974 El área caolinera del Departamento de Gaimán, Provincia de Chubut 423444.Google Scholar
Rozanski, K. Araguás-Araguás, L. Gonfiantini, R., Swart, P.K. Lohmann, K.C. McKenzie, J. and Savin, S., 1993 Isotopic patterns in modern global precipitation Climate Change in Continental Isotopic Records. Geophysical Monograph 78 Washington, DC. American Geophysical Union 136.Google Scholar
Savin, S.M. and Epstein, S., 1970 The oxygen and hydrogen isotope geochemistry of clay minerals Geochimica et Cosmochimica Acta 34 2542 10.1016/0016-7037(70)90149-3.CrossRefGoogle Scholar
Scotese, C. Gahagan, L. and Larson, R., 1988 Plate tectonic reconstruction of the Cretaceous and Cenozoic ocean basins Tectonophysics 155 2748 10.1016/0040-1951(88)90259-4.CrossRefGoogle Scholar
Schira, W., 1991 Die Südliche Küstenkordillere Chiles .Google Scholar
Schoen, R. White, D.E. and Hemley, J.J., 1974 Argilliza-tion by descending acid at Steamboat Springs, Nevada Clays and Clay Minerals 22 122 10.1346/CCMN.1974.0220104.CrossRefGoogle Scholar
Sheppard, S.M.F., 1977 The Cornubian batholith, SW England: D/H and 18O/16O studies of kaolinite and other alteration minerals Journal of the Geological Society (London) 133 573591 10.1144/gsjgs.133.6.0573.CrossRefGoogle Scholar
Sheppard, S.M.F. and Gilg, H.A., 1996 Stable isotope geochemistry of clay minerals Clay Minerals 31 124 10.1180/claymin.1996.031.1.01.CrossRefGoogle Scholar
Sheppard, S.M.F. and Gustafson, L.B., 1976 Oxygen and hydrogen isotopes in the porphyry copper deposit at El Salvador, Chile Economic Geology 71 15491559 10.2113/gsecongeo.71.8.1549.CrossRefGoogle Scholar
Sheppard, S.M.E. Nielsen, R.L. and Taylor, H.P., 1969 Oxygen and hydrogen isotope ratios of clay minerals from porphyry copper deposits Economic Geology 64 755777 10.2113/gsecongeo.64.7.755.CrossRefGoogle Scholar
Walker, G.F. and Heller, L., 1970 Discussion of J. Konta: Comparison of the proofs of hydrothermal and supergene kaolinization in two areas of Europe Proceedings of the International Clay Conference, Tokyo, Volume 2 9193.Google Scholar
Weischet, W., 1970 Chile, Seine Landeskundliche Individulität und Struktur Darmstadt Wissenschaftliche Buchgesellschaft 268365.Google Scholar
Yapp, C.J., 1987 Oxygen and hydrogen isotope variations among goethites (α-FeOOH) and determination of paleo-temperatures Geochimica et Cosmochimica Acta 51 355364 10.1016/0016-7037(87)90247-X.CrossRefGoogle Scholar