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Pedogenic formation of smectites in a vertisol developed from granitic rock from Kaélé (Cameroon, Central Africa)

Published online by Cambridge University Press:  09 July 2018

J. P. Nguetnkam
Affiliation:
Département des Sciences de la Terre, Faculté des Sciences, Université de Ngaoundéré, BP 454, Ngaoundéré, Cameroon Laboratoire Environnement et Minéralurgie, UMR 7569, Nancy-Université - CNRS, BP 40, 545001 Vandoeuvre-lès-Nancy, France
R. Kamga
Affiliation:
Département de Chimie Appliquée, Ecole Nationale Supérieure des Sciences agroindustrielles, Université de Ngaoundéré, BP 455, Ngaoundéré, Cameroon
F. Villiéras*
Affiliation:
Laboratoire Environnement et Minéralurgie, UMR 7569, Nancy-Université - CNRS, BP 40, 545001 Vandoeuvre-lès-Nancy, France
G. E. Ekodeck
Affiliation:
Département des Sciences de la Terre, Faculté des Sciences, Université de Yaoundé I, BP 812, Yaoundé, Cameroon
J. Yvon
Affiliation:
Laboratoire Environnement et Minéralurgie, UMR 7569, Nancy-Université - CNRS, BP 40, 545001 Vandoeuvre-lès-Nancy, France
*

Abstract

Smectite formation in a vertisol developed from a granitic parent rock in the Kaélé region of Cameroon in a tropical, dry climate was studied by means of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), chemical analyses, cation exchange capacity (CEC) and low temperature gas adsorption. The soil profile comprises three horizons (from base to top): (1) a saprolite, (2) an intermediate horizon, and (3) an upper dark grey horizon. In the saprolite, the progressive alteration of feldspars gave rise to the exclusive neoformation of beidellite exhibiting a typical honeycomb fabric. This process resulted in Al, Fe, Ca, Mg, Ti and Mn enrichment, a depletion of Si and Na and a significant negative Eu anomaly. In the upper horizons, beidellite evolves and is transformed into montmorillonite and kaolinite, probably through a series of smectite-kaolinite mixed layers. This transformation, from the saprolite to the upper horizons, causes the observed decrease in the CEC and the increase in specific surface area and mesoporosity of the clay. The REE patterns of the bulk soil and clay fraction display similar behaviour, indicating that the three horizons, and hence the clay minerals, have a common source in the underlying granite. Mass-balance calculations show that the intense weathering of the granite leads to a mass reduction of ~80–90%.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2007

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References

Amouric, M. & Olives, J. (1998) Transformation mechanisms and interstratification in conversion of smectite to kaolinite; an HRTEM study. Clays and Clay Minerals, 46, 521527.Google Scholar
Aoudjit, H., Robert, M., Elsass, F. & Curmi, P. (1995) Detailed study of smectite genesis in granitic saprolites by analytical electron microscopy. Clay Minerals, 30, 135147.CrossRefGoogle Scholar
Aubert, D., Stille, P. & Probst, A. (2001) REE fractionation during granite weathering and removal by waters and suspended loads: Sr and Nd isotope evidence. Geochimica et Cosmochimica Acta, 65, 387406.Google Scholar
Banfield, J.F., Jones, B.F. & Veblen, D.R. (1991) An AEM-TEM study of weathering and diagenesis, Albert Lake, Oregon: I. Weathering reactions in the volcanics. Geochimica et Cosmochimica Acta, 55, 27812793.CrossRefGoogle Scholar
Barrett, E.P., Joyner, L.G. & Halenda, P.P. (1951) The determination of pore volume and area distributions in porous substances. I. Computation from nitrogen isotherms. Journal of the American Chemical Society, 73, 373380.Google Scholar
Bilong, P., Eno Bélinga, S.M. & Volkoff, B. (1992) Séquence d’évolution des paysages cuirassés et des sols ferrallitiques en zone forestière tropicale d’Afrique Centrale. Place des sols à horizon d’argile tachetée. Comptes Rendus de l'Académie des Sciences, 314, 109115.Google Scholar
Bitom, D., Volkoff, B. & Abossolo-Angue, M. (2003) Evolution and alteration in situ of a massive iron duricrust in Central Africa. Journal of African Earth Sciences, 37, 89101.CrossRefGoogle Scholar
Braun, J.J., Pagel, M., Herbillon, A. & Rosin, C. (1993) Mobilization and redistribution of REEs and Thorium in a syenite lateritic profile: a mass balance study. Geochimica et Cosmochimica Acta, 57, 44194434.Google Scholar
Brunauer, S., Emmet, P.H. & Teller, E. (1938) Adsorption of gases in multimolecular layers. Journal of the American Chemical Society, 60, 309319.CrossRefGoogle Scholar
Christidis, G. & Dunham, A.C. (1993) Compositional variations in smectites. Part I: alteration of intermediate volcanic rocks. A case study from Milos Island, Greece. Clay Minerals, 28, 255273.CrossRefGoogle Scholar
Christidis, G.E., Scott, P.W. & Dunham, A.C. (1997) Acid activation and bleaching capacity of bentonites from the islands of Milos and Chios, Aegean. Applied Clay Science, 12, 329347.CrossRefGoogle Scholar
Çoban, F. & Ece Işik, Ö. (1999) Fe3+-rich montmor-illonite-beidellite series in Ayvacik bentonite deposit, Biga Peninsula, Northwest Turkey. Clays and Clay Minerals, 47, 165173.Google Scholar
Condie, K.C., Dengate, J. & Culler, R.L. (1995) Behavior of rare earth elements in a paleoweathering profile on granodiorite in the Front Range, Colorado, USA. Geochimica et Cosmochimica Acta, 59, 279294.CrossRefGoogle Scholar
Crovisier, J.L., Honnorez, J., Fritz, B. & Petit, J.C. (1992) Dissolution of basaltic glass in seawater: mechanism and rate. Geochimica et Cosmochimica Acta, 51, 29772990.CrossRefGoogle Scholar
De Boer, J.H., Lippens, B.C., Linsen, B.G., Brokhoff, J.C.P., Van Der Heuvel, A. & Osinga, T.J. (1966) The t-curve of multimolecular N2 adsorption. Journal of Colloid and Interface Science, 21, 405414.CrossRefGoogle Scholar
Ekodeck, G.E. (1976) Contribution à l’étude de la nature et du comportement géotechnique des dépôts superficiels gonflants du Nord Cameroun. PhD Thesis. University of Grenoble, France.Google Scholar
Fiore, S. (1993) The occurrence of smectite and illite in a pyroclastic deposit prior to weathering: implication on the genesis of 2:1 clay minerals in volcanic soils. Applied Clay Science, 8, 249259.Google Scholar
Fiore, S., Huertas, F.J., Huertas, F. & Linares, J. (2001) Smectite formation in rhyolitic obsidian as inferred by microscopy (SEM-TEM-AEM) investigation. Clay Minerals, 36, 489500.CrossRefGoogle Scholar
Greene-Kelly, R. (1957) The montmorillonite minerals (smectites). Pp. 5359 in: Differential Thermal Investigation of Clays (Mackenzie, S., editor). Mineralogical Society, London.Google Scholar
Herbillon, A.J., Frankart, R. & Vielvoye, L. (1981) An occurrence of interstratified kaolinite-smectite minerals in a red-black soil toposequence. Clay Minerals, 16, 195201.Google Scholar
Hoffman, U. & Klemen, R. (1950) Verlust der austauschf#x00E4;higkeit von lithiumioen und bentonit durch erhitzung. Zeitschrift für Anorganische Chemie, 262, 9599.CrossRefGoogle Scholar
Jaynes, W.F., Bigham, J.M., SmeckN.E. & Shipitalo, M.J. (1989) Interstratified 1:1-2:1 mineral formation in a polygenetic soil from southern Ohio. Soil Science Society of America Journal, 53, 18881894.CrossRefGoogle Scholar
Kawano, M. & Tomita, K. (1992) Formation of allophane and beidellite during hydrothermal alteration of volcanic glass below 200ºC. Clays and Clay Minerals, 40, 666674.Google Scholar
Kawano, M. & Tomita, K. (1993) Growth of smectite from leached layer during experimental alteration of albite. Clays and Clay Minerals, 42, 717.CrossRefGoogle Scholar
Keeling, J.L., Raven, M.D. & Gates, W.P. (2000) Geology and characterization of two hydrothermal nontronites from weathered metamorphic rocks at the Uley Graphite Mine, South Australia. Clays and Clay Minerals, 48, 537548.Google Scholar
Kloprogge, J.T., Jansen, J.B.H. & Geus, J.W. (1990) Characterization of synthetic Na beidellite. Clays and Clay Minerals, 38, 409414.CrossRefGoogle Scholar
Kloprogge, J.T., van der Eerden, A.M.J., Jansen, J.B.H., Geus, J.W. & Schuiling, R.D. (1993) Synthesis and paragenesis of Na-beidellite as function of temperature, water pressure and sodium activity. Clays and Clay Minerals, 41, 423430.CrossRefGoogle Scholar
Kloprogge, J.T., Komarneni, S. & Amonette, J.E. (1999) Synthesis of smectite clay minerals: a critical review. Clays and Clay Minerals, 47, 529554.Google Scholar
Li, G., Peacor, D.R. & Coombs, D.S. (1997) Transformation of smectite to illite in bentonite and associated sediments from Kaka Point, New Zealand: contrasts in rate and mechanism. Clays and Clay Minerals, 45, 5467.CrossRefGoogle Scholar
Lima de Souza, D. (2005) Etude pétrologique et cristallochimique du bassin de la rivière Capim: Para. Implications industrielles. PhD Thesis, INPL, France and Ouro Preto Federal University (Brasil).Google Scholar
Masuda, H., O’Neil, J.R., Jiang, W.T. & Peacor, D.R. (1996) Relation between interlayer composition of authigenic smectite, mineral assemblages, I/S reaction rate and fluid composition in silicic ash of the Nankai Trough. Clays and Clay Minerals, 44, 443459.CrossRefGoogle Scholar
McDonough, W.F. & Sun, S.S. (1995) The composition of the earth. Chemical Geology, 120, 223225.Google Scholar
Meunier, A. (2003) Les argiles. Collection geosciences, GB Science Publisher.Google Scholar
Mizota, C. & Faure, K. (1998) Hydrothermal origin of smectite in volcanic ash. Clays and Clay Minerals, 46, 178192.CrossRefGoogle Scholar
Morgan, D.A., Shaw, D.B., Sidebottom, M.J., Soon, T.C. & Taylor, R.S. (1985) The function of bleaching earths in the processing of palm, palm kernel and coconut oils. Journal of the American Oil Chemists Society, 62, 292299.CrossRefGoogle Scholar
Nesbitt, H.W. & Muir, I.J. (1988) SIMS depth profiles of weathered plagioclase and processes affecting Al and Si in some acidic solutions. Nature, 334, 336338.Google Scholar
Nguetnkam, J.P., Bitom, D., Yongue, R., Bilong, P., Eno Bélinga, S.M. & Volkoff, B. (2003) Etude pétrographique, minéralogique et géochimique d’une toposé-quence de sols développés sur granite dans le plateau forestier de l’Adamaoua. Science and Technology Development, 10, 3543.Google Scholar
Nguetnkam, J.P., Yongue, R., Bitom, D., Bilong, P. & Volkoff, B. (2006) Etude pétrologique d’une formation latéritique sur granite en milieu tropical forestier sud-camerounais (Afrique centrale): mise en évidence de son caractère polyphasé. Etude et Gestion des sols, 13, 89102.Google Scholar
Righi, D. & Meunier, A. (1995) Origin of clays by rock weathering and soil formation. Pp. 43157 in: Origin and Mineralogy of Clays (Velde, B., editor). Springer-Verlag, Heidelberg, Germany.Google Scholar
Righi, D., Fabio, T. & Petit, S. (1999) Pedogenic formation of kaolinite-smectite mixed layers in a soil toposequence developed from basaltic parent material in Sardinia (Italy). Clays and Clay Minerals, 47, 505514.CrossRefGoogle Scholar
Sharma, A. & Rajamani, V. (2000) Weathering of charnockites and sediment production in the catchment area of the Cauvery River, southern India. Sedimentary Geology, 143, 169184.CrossRefGoogle Scholar
Taboada, T. & Garcia, C. (1999) Smectite formation produced by weathering in a coarse granite saprolite in Galicia (NW Spain). Catena, 35, 281290.Google Scholar
Tazaki, K. (1986) Observation of primitive clay precursors during microcline weathering. Contributions to Mineralogy and Petrology, 92, 8688.CrossRefGoogle Scholar
Tazaki, K. & Fyfe, W.S. (1987a) Formation of primitive clay precursors on K-feldspar under extreme leaching conditions. Pp. 5358 in: Proceedings of the International Clay Conference, Denver, 1985 (Schultz, L.G., Van Olphen, H. & Mumpton, F.A., editors). The Clay Mineralogy Society, Bloomington, Indiana.Google Scholar
Tazaki, K. & Fyfe, W.S. (1987b) Primitive clay precursors formed on feldspar. Canadian Journal of Earth Sciences, 24, 506527.CrossRefGoogle Scholar
Tématio, P., Kegni, L., Bitom, D., Hodson, M., Fopoussi, J.C., Leumbe, O., Mpakam, J.M. & Tsozué, D. (2004) Soils and their distribution on Bamboutos volcanic mountain, West Cameroon Highland, Central Africa. Journal of African Earth Sciences, 39, 447457.Google Scholar
Tomita, K., Yamane, H. & Kawano, M. (1993) Synthesis of smectite from volcanic glass at low temperature. Clays and Clay Minerals, 41, 655661.Google Scholar
Van Olphen, H. & Fripiat, J.J. (1979) Data Handbook for Clay Materials and Other Non-Metallic Minerals. Pergamon Press, Oxford, UK.Google Scholar
Velde, B. (1992) Introduction to Clay Minerals. Chemistry, Origins, Uses and Environmental Significance. Chapman & Hall, London.Google Scholar
Velde, B. (1995) Origin and Mineralogy of Clays. Clays and the Environment. Springer, Berlin.Google Scholar
Villiéras, F., Chamerois, M., Bardot, F. & Michot, L.J. (2002) Evaluation of wetting properties of powders from gas adsorption experiments. Pp. 435447 in: Contact Angle, Wettability and Adhesion, Volume 2 (Mittal, K.L., editor), VSP, Utrecht, The Netherlands.Google Scholar
Wakponou, A. (1995) Signification paléogéographique des formations superficielles à la bordure sud du bassin du Tchad au Cameroun. Etude géomorphologique. PhD Thesis, University de Yaounde I, Cameroon.Google Scholar
Yamada, H., Yoshioka, K., Fujii, K. & Nakazawa, H. (1999) Compositional gap in dioctahedral-trioctahedral smectite system: beidellite-saponite pseudobinary join. Clays and Clay Minerals, 47, 803810.Google Scholar
Yerima, B.P.K., Calhoun, F.G., Senkayi, A.L. & Dixon, J.B. (1985) Occurrence of interstratified kaolinite-smectite in El Salvador Vertisols. Soil Science Society of America Journal, 49, 462466.CrossRefGoogle Scholar