Hostname: page-component-848d4c4894-2xdlg Total loading time: 0 Render date: 2024-07-06T17:00:15.907Z Has data issue: false hasContentIssue false
  • English
  • Français

Biotite Alteration in Deeply Weathered Granite. I. Morphological, Mineralogical, and Chemical Properties

Published online by Cambridge University Press:  01 July 2024

R. J. Gilkes  and
Anchalee Suddhiprakarn
R. J. Gilkes
Affiliation:
Department of Soil Science and Plant Nutrition, University of Western Australia, Nedlands, Western Australia, Australia 6009
Anchalee Suddhiprakarn*
Affiliation:
Department of Soil Science and Plant Nutrition, University of Western Australia, Nedlands, Western Australia, Australia 6009
*
1Permanent address: Department of Soil Science, Kasetsart University, Bangkok, Thailand.
Get access Rights & Permissions [Opens in a new window]

Abstract

Biotite in deeply weathered granitic rocks in southwestern Australia has altered to exfoliated grains composed of biotite, mixed-layer clay minerals, kaolinite, vermiculite, gibbsite, goethite, and hematite. Discrete vermiculite and vermiculite-dominant mixed-layer clay minerals are not major weathering products. Oxidation of octahedral iron in biotite is associated with ejection of octahedral cations, loss of interlayer K, and a contraction of the b-dimension of the biotite sheet. Si, Mg, Ca, Mn, K, and Na are lost from biotite during weathering, and Ti, Al, Ni, and Cr are retained. Fe and water have been added to the grains during weathering. Much Fe occurs as aggregates of microcystalline, aluminum-rich goethite particles on flake surfaces and within etchpits, with smaller amounts occurring as hexagonal arrangements of lath-shaped crystals of goethite on flake surfaces.

Резюме

Резюме

Биотит в глубоко выветренных гранитных породах в юго-западной Австралии был изменен в расслоенные зерна, состоящие из биотита, смешанно-слойных минералов, каолинита, вермикулита, гиббсита, гетита, и гематита. Дискретный вермикулит и смешанно-слойные глинистые минералы, в основном содержащие вермикулит, не являются основными продуктами выветривания. Окисление октаэдрического железа в биотите ассоциируется с выбросом октаедри-ческих катионов, потерей межслойного К, и сокращением Ь-измерения пластин биотита. Si, Мg, Са, Мп, К, и Nа высвобождается из биотита во время выветривания, а Тi, Аl, Ni, и Сг остаются. Во время выветривания в зернах появляется добавочная вода и Ре. Много Ре встречается в виде агрегатов микрокристаллических богатых алюминием гетитовых частиц на чешуйчатых поверхностях, меньшие количества встречаются в виде гексагонально расположенных пластинчатых кристаллов гетита на чешуйчатых поверхностях.

Resümee

Resümee

Der Biotit in den tiefgründig verwitterten, granitischen Gesteinen von Südwest-Australien ist in schuppige Körner umgewandelt, die aus Biotit, Wechsellagerungen, Kaolinit, Vermiculit, Gibbsit, Goethit, und Hämatit bestehen. Einzelne, diskrete Vermiculite und vorwiegend aus Vermiculit bestehende Wechsellagerungen kommen dagegen nicht oft als Verwitterungsprodukte vor. Die Oxidation des okta-edrischen Eisens im Biotit ist mit dem Austritt von oktaedrischen Kationen, dem Verlust von Kalium aus den Zwischenschichten und einer Verkleinerung der Biotitschicht in Richtung der b-Achse verbunden. Während der Verwitterung verarmt der Biotit an Si, Mg, Ca, Mn, K, und Na, während Ti, Al, Ni, und Cr zurückgehalten werden. Fe und Wasser werden den Körnern während der Verwitterung zugeführt. Ein großer Teil des Fe ist in Form von Aggregaten aus mikrokristallinen, aluminiumreichen Goethitpartikeln auf den Blättchenoberflächen und in Atzgruben vorhanden. Ein kleiner Teil kommt in Form von hexagon-alen Anordnungen aus leistenförmigen Goethitkristallen auf den Blättchenoberflächen vor.

Résumé

Résumé

La biotite dans des roches granitiques profondément altérées d'Australie du Sud-ouest a été altérée en grains exfoliés composés de biotite, de minéraux argileux à couches mélangées, de kaolinite, de vermiculite, de gibbsite, de goethite, et d'hématite. La vermiculite elle-même, et les minéraux argileux à couches mélangées à prédominance de vermiculite ne sont pas des produits d'altération majeurs. L'oxidation de fer octaédrique dans la biotite est associée avec l’éjection de cations octaédriques, avec la perte de l'intercouche K, et avec la contraction de la dimension-b de la feuille de biotite. Si, Mg, Ca, Mn, K, et Na sont perdus par la biotite pendant l'altération, et Ti, Al, Ni, and Cr sont retenus. Fe et de l'eau ont été ajoutés aux grains pendant l'altération. Beaucoup de Fe existe comme aggrégats de particules de goethite microcristallins et riches en aluminium sur des surfaces de lame et dans des crevasses gravées, avec des quantités moindres existant comme arrangements hexagonaux de cristaux de goethite en forme de latte sur les surfaces des lames.

Keywords

BiotiteGoethiteMixed-layer mineralSEM morphologyVermiculiteWeathering
Type
Research Article
Information
Clays and Clay Minerals , Volume 27 , Issue 5 , October 1979 , pp. 349 - 360
Copyright
Copyright © 1979, The Clay Minerals Society

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Brindley, G. W. and MacEwan, D. M. C. (1953) Structural aspects of the mineralogy of clays: in Ceramics—a symposium, British Ceramic Society, Stoke-on-Trent, 15–69.Google Scholar
Eswaran, H. and Bin, W. C. (1978) A study of a deep weathering profile on granite in Peninsular Malaysia: III. Alteration of feldspars: Soil Sci. Soc. Am. J. 42, 154–158.CrossRefGoogle Scholar
Eswaran, H. and Heng, Y. Y. (1976) The weathering of biotite in a profile on gneiss in Malaysia: Geoderma 16, 9–20.CrossRefGoogle Scholar
Fanning, D. S. and Keramidas, V. Z. (1977) Micas: in Minerals in Soil Environments, Dixon, J. B. and Weed, S. B., eds., Soil Science Society of America, Madison, Wisconsin, 195–258.Google Scholar
Farmer, V. C., Russell, J. D., McHardy, W. J., Newman, A. C. D., Alhrichs, J. L., and Rimsaite, J. Y. H. (1971) Evidence for loss of protons and octahedral iron from oxidized biotites and vermiculites: Mineral. Mag. 38, 121–137.CrossRefGoogle Scholar
Gandolfi, G. (1967) Discussion upon methods to obtain X-ray powder patterns from a single crystal: Mineral. Petrogr. Acta 13, 67–74.Google Scholar
Gilkes, R. J. (1973) The alteration products of potassium-depleted oxybiotite: Clays & Clay Minerals 21, 303–313.CrossRefGoogle Scholar
Gilkes, R. J. and Suddhiprakarn, A. (1979) Biotite alteration in deeply weathered granite II. The oriented growth of secondary minerals: Clays & Clay Minerals 27, 361–367.CrossRefGoogle Scholar
Gilkes, R. J., Young, R. C., and Quirk, J. P. (1972) The oxidation of octahedral iron in biotite: Clays & Clay Minerals 20, 303–315.CrossRefGoogle Scholar
Jackson, M. L., Lee, S. Y., Brown, J. L., Sachs, I. B., and Syers, J. K. (1973) Scanning electron microscopy of hydrous metal oxide crusts intercalated in naturally weathered micaceous vermiculite: Soil Sci. Soc. Amer. Proc. 37, 127–131.CrossRefGoogle Scholar
Kato, Y. (1965) Mineralogical study of weathering products of granodiorite at Shinshiro City: Weathering of primary minerals, mineralogical characteristics of weathered mineral grains: Soil Sci. Plant Nutr. (Tokyo) 11, 30–40.CrossRefGoogle Scholar
Klug, H. P. and Alexander, L. E. (1974) X-ray Diffraction Procedures for Polycrystalline and Amorphous Materials: Wiley, New York, 966 pp.Google Scholar
Leonard, R. A. and Weed, S. B. (1970) Effects of potassium removal on the b-dimension of phlogopite: Clays & Clay Minerals 18, 197–202.CrossRefGoogle Scholar
Mitchell, R. L. (1964) Trace elements in soils: in Chemistry of the Soil, Bear, F. E., ed., Reinhold, New York, 320–366.Google Scholar
Norrish, K. (1973) Factors in the weathering of mica to vermiculite: Proc. 1972 Int. Clay Minerals Conf., Madrid, 417–432.Google Scholar
Norrish, K. and Hutton, J. T. (1969) An accurate X-ray spectrographic method for the analysis of a wide range of geological samples: Geochim. Cosmochim. Acta 33, 431–453.CrossRefGoogle Scholar
Norrish, K. and Taylor, R. M. (1961) The ismorphous replacement of iron by aluminium in soil goethite: J. Soil Sci. 12, 294–306.CrossRefGoogle Scholar
Radoslovich, E. W. (1963) Cell dimension studies on layer lattice silicates: A summary: Clays & Clay Minerals 11, 225–228.Google Scholar
Radoslovich, E. W. (1975) Micas in macroscopic forms: in Soil Components: Vol. 2—Inorganic Components, Gieseking, J. E., ed., Springer Verlag, New York, 27–57.CrossRefGoogle Scholar
Reichenbach, H. Graf von and Rich, C. I. (1975) Fine-grained micas in soils: in Soil Components: Vol. 2—Inorganic Components, Gieseking, J. E., ed., Springer Verlag, New York, 59–95.CrossRefGoogle Scholar
Rhoades, J. D. and Coleman, N. T. (1967) Interstratification in vermiculite and biotite produced by potassium sorption. I. Evaluation by simple X-ray diffraction pattern inspection: Soil Sci. Soc. Amer. Proc. 31, 366–372.CrossRefGoogle Scholar
Ruiz-Amil, A., Garcia, A. R., and MacEwan, D. M. C. (1967) X-ray Diffraction Curves for the Analysis of Interstratified Structures: Volturna Press, Edinburgh.Google Scholar
Sadleir, S. B. and Gilkes, R. J. (1976) Development of bauxite in relation to parent material near Jarrahdale, Western Australia: J. Geol. Soc. Aust. 23, 333–344.CrossRefGoogle Scholar
Sawhney, B. L. (1967) Interstratification in vermiculite: Clays & Clay Minerals 15, 75–84.CrossRefGoogle Scholar
Schwertmann, U. and Taylor, R. M. (1977) Iron oxides: in Minerals in Soil Environments, Dixon, J. B. and Weed, S. B., eds., Soil Science Society of America, Madison, Wisconsin, 145–176.Google Scholar
Suito, E. and Nakahira, M. (1971) Micas and related minerals: in The Electron-Optical Investigation of Clays, Gard, J. A., ed., Mineralogical Society, London, 231–255.CrossRefGoogle Scholar