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Weathering of Chlorite to a Low-Charge Expandable Mineral in a Spodosol on the Apennine Mountains, Italy

Published online by Cambridge University Press:  28 February 2024

Stefano Carnicelli
Affiliation:
Dipartimento di Scienza del Suolo e Nutrizione della Pianta, Università di Firenze, Ple Cascine 16, 50144 Firenze, Italy
Aldo Mirabella
Affiliation:
Istituto Sperimentale per lo Studio e la Difesa del Suolo., MiRAAF P.za D'Azeglio 30, 50121 Firenze, Italy
Guia Cecchini
Affiliation:
Dipartimento di Scienza del Suolo e Nutrizione della Pianta, Università di Firenze, Ple Cascine 16, 50144 Firenze, Italy
Guido Sanesi
Affiliation:
Dipartimento di Scienza del Suolo e Nutrizione della Pianta, Università di Firenze, Ple Cascine 16, 50144 Firenze, Italy
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Abstract

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The clay fraction of a Spodosol and its parent rock in the Apennine mountains of central Italy were studied by powder X-raydiffraction (XRD) and infrared (IR) spectroscopy, to evaluate the possibility of transformation of chlorite into low-charge expandable minerals. Results indicated that the main phyllosilicate in the rock was a slightly weathered trioctahedral chlorite, rich in both Mg and Fe, together with dioctahedral mica and minor amounts of kaolinite. In the BC horizon, chlorite has undergone partial transformation into 2 vermiculitic components, in 1 of which the interlayer could be removed by hot Na-citrate treatment; the presence of a regular interstratified mineral (high-charge corrensite) was also observed. Further changes in the structure of chlorite were detected in the Bsl horizon, becoming more evident towards the soil surface. The first stage of weathering of chlorite involved Fe oxidation and partial expulsion of Mg from the hydroxide sheet, followed by deposition of Al in the interlayer space. Iron is also removed from the interlayer sheet, possibly remaining, in the oxidized state, in the 2:1 octahedral sheet, and so contributing to the lowering of layer charge and transformation to a dioctahedral structure. When approaching the surface, Al removal from the interlayers is enhanced by complexing agents, and further charge reduction leads to the formation of 2:1 minerals with a smectite nature. Illite, because of its low content in the soil clay fraction, contributes marginally to this weathering sequence, forming the high charged expandable component observed in the Bhs horizon. At the soil surface, arandomly interstratified vermiculite/illite was detected, which probably originated from K fixation by the higher-charged expandable minerals. This study of weathering in a natural soil strongly supports the hypothesis, previously ascertained by laboratory experiments, that chlorite can transform into a low-charge expandable mineral.

Type
Research Article
Copyright
Copyright © 1997, The Clay Minerals Society

References

April, R.H., Hluchy, M.M. and Newton, R.M.. 1986. The nature of vermiculite in Adirondack soils and till. Clays Clay Miner 34: 549556.CrossRefGoogle Scholar
Bailey, S.W.. 1975. Chlorites. In: Gieseking, J.E., editor. Soil components, vol 2: Inorganic components. Berlin: Springer-Verlag. p 191263.CrossRefGoogle Scholar
Barnhisel, R.I. and Bertsch, P.M.. 1989. Chlorites and hydroxy-interlayered vermiculite and smectite. In: Dixon, J.B., Weed, S.B., editors. Minerals in soil environments. Madison, WI: Soil Sci Soc Am. p 729788.Google Scholar
Brown, G. and Brindley, G.W.. 1980. X-ray diffraction procedures for clay mineral identification. In: Brindley, G.W., Brown, G., editors. Crystal structures of clay minerals and their X-ray identification. London: Mineral Soc. p 305360.CrossRefGoogle Scholar
Carnicelli, S., Cecchini, G., Mirabella, A. and Sanesi, G.. 1994. Composizione della soluzione e mineralogia della frazione argillosa nei suoli delle faggete di Pian di Novello (PT). Atti del XII Congresso della Società Italiana di Chimica Agraria; 1994; Piacenza. p 5764.Google Scholar
Cho, H.D. and Mermut, A.R.. 1992. Evidence for halloysite formation from weathering of ferruginous chlorite. Clays Clay Miner 40: 608619.Google Scholar
Coen, G.M. and Arnold, R.W.. 1972. Clay mineral genesis of some New York Spodosols. Soil Sci Soc Am Proc 36: 342350.CrossRefGoogle Scholar
Dalian, L., Puccinelli, A. and Verani, M.. 1981. Geologia dell'Appennino Settentrionale tra l'alta Val di Lima e Pistoia (note illustrative della carta geologica alla scala 1: 25,000). Boll Soc Geol It 100: 567586.Google Scholar
Douglas, L.A.. 1989. Vermiculites. In: Dixon, J.B., Weed, S.B., editors. Minerals in soil environments. Madison, WI: Soil Sci Soc Am. p 635674.Google Scholar
Eberl, D.D., Środoń, J. and Northrop, H.R.. 1986. Potassium fixation by wetting and drying. In: Davis, J.A., Hayes, K.F., editors. Geochemical processes at mineral surfaces. Am Chem Soc Symp Ser 323: 296326.CrossRefGoogle Scholar
Enzo, S., Fagherazzi, G., Benedetti, A. and Polizzi, S.. 1988. A profile-fitting procedure for analysis of broadened X-ray diffraction peaks: I. Methodology. J Appl Crystallogr 21: 536542.CrossRefGoogle Scholar
Farmer, V.C.. 1974. The layer silicates. In: Farmer, V.C., editor. The infrared spectra of minerals. Monograph 4. London: Mineral Soc. p 331363.CrossRefGoogle Scholar
Herbillon, A.J. and Makumbi, M.N.. 1975. Weathering of chlorite in a soil derived from a chloritoschist under humid tropical conditions. Geoderma 13: 89104.CrossRefGoogle Scholar
Howard, S.A. and Preston, K.D.. 1989. Profile fitting of powder diffraction patterns. In: Bish, D.L., Post, J.E., editors. Modern powder diffraction. Reviews in mineralogy, 20. Washington DC: Mineral Soc Am. p 217275.CrossRefGoogle Scholar
MacEwan, D.M.C. and Wilson, M.J.. 1980. Interlayer and intercalation complexes of clay minerals. In: Brindley, G.W., Brown, G., editors. Crystal structures of clay minerals and their X-ray identification. London: Mineral Soc. p 197248.CrossRefGoogle Scholar
Malcolm, R.L., Nettleton, W.D. and McCracken, R.J.. 1969. Pedogenic formation of montmorillonite from a 2: 1–2: 2 inter-grade clay mineral. Clays Clay Miner 16: 405414.CrossRefGoogle Scholar
Marel, HW van der and Beutelspacher, H.. 1976. Atlas of infrared spectroscopy of clay minerals and their admixtures. Amsterdam: Elsevier Science. 396 p.Google Scholar
Moore, D.M. and Reynolds, R.C. Jr. 1989. X-ray diffraction and the identification and analysis of clay minerals. Oxford: Oxford Univ Pr. 332 p.Google Scholar
Proust, D., Eymery, J.P. and Beaufort, D.. 1986. Supergene vermi-culitization of a magnesian chlorite: Iron and magnesium removal processes. Clays Clay Miner 34: 572580.CrossRefGoogle Scholar
Righi, D., Bravard, S., Chauvel, A., Ranger, J. and Robert, M.. 1990. In situ study of soil processes in an Oxisol-Spodosol sequence of Amazonia (Brazil). Soil Sci 150: 438445.CrossRefGoogle Scholar
Righi, D. and Meunier, A.. 1991. Characterization and genetic interpretation of clays in an acid brown soil (Dystrochrept) developed in a granitic saprolite. Clays Clay Miner 39: 519530.CrossRefGoogle Scholar
Righi, D., Petit, S. and Bouchet, A.. 1993. Characterization of hydroxy-interlayered vermiculite and illite/smectite interstratified minerals from the weathering of chlorite in a Cryorthod. Clays Clay Miner 41: 484495.CrossRefGoogle Scholar
Ross, G.J.. 1975. Experimental alteration of chlorites into vermiculites by chemical oxidation. Nature 255: 133134.CrossRefGoogle Scholar
Ross, G.J.. 1980. The mineralogy of Spodosols. In: Theng, B.K.G., editor. Soils with variable charge. Lower Hutt, New Zealand: Soil Bureau, Department of Scientific and Industrial Research, p 127143.Google Scholar
Ross, G.J. and Kodama, H.. 1976. Experimental alteration of a chlorite into a regularly interstratified chlorite-vermiculite by chemical oxidation. Clays Clay Miner 24: 183190.CrossRefGoogle Scholar
Russell, J.D.. 1987. Infrared methods. In: Wilson, M.J., editor. A handbook of determinative methods in clay mineralogy. Glasgow: Blackie. p 133173.Google Scholar
Senkayi, A.L., Dixon, J.B. and Hossner, L.R.. 1981. Transformation of chlorite to smectite through regularly interstratified intermediates. Soil Sci Soc Am J 45: 650656.CrossRefGoogle Scholar
Tamura, T.. 1958. Identification of clay minerals from acid soils. J Soil Sci 9: 141147.CrossRefGoogle Scholar
Vicente, M.A., Razzaghe, M. and Robert, M.. 1977. Formation of aluminium hydroxy vermiculite (intergrade) and smectite from mica under acidic conditions. Clay Miner 12: 101111.CrossRefGoogle Scholar
Wada, K., Kakuto, Y., Wilson, M.A. and Hanna, J.V.. 1991. The chemical composition and structure of a 14 A intergradient mineral in a Korean Ultisol. Clay Miner 26: 449461.CrossRefGoogle Scholar
Weaver, C.E.. 1989. Clays, muds and shales. Developments in sedimentology, 44. Amsterdam: Elsevier Science. 819 p.Google Scholar
Wilson, M.J.. 1986. Mineral weathering processes in Podzolic soils on granitic materials and their implications for surface water acidification. J Geol Soc, London 143: 691697.CrossRefGoogle Scholar
Wilson, M.J.. 1987. X-ray powder diffraction methods. In: Wilson, M.J., editor. A handbook of determinative methods in clay mineralogy. Glasgow and London: Blackie. p 2698.Google Scholar