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Weathering microenvironments on feldspar surfaces: implications for understanding fluid-mineral reactions in soils

  • M. R. Lee (a1), D. J. Brown (a1), M. E. Hodson (a2), M. Mackenzie (a3) and C. L. Smith (a1)...

Abstract

The mechanisms by which coatings develop on weathered grain surfaces, and their potential impact on rates of fluid-mineral interaction, have been investigated by examining feldspars from a 1.1 ky old soil in the Glen Feshie chronosequence, Scottish highlands. Using the focused ion beam technique, electron-transparent foils for characterization by transmission electron microscopy were cut from selected parts of grain surfaces. Some parts were bare whereas others had accumulations, a few micrometres thick, of weathering products, often mixed with mineral and microbial debris. Feldspar exposed at bare grain surfaces is crystalline throughout and so there is no evidence for the presence of the amorphous ‘leached layers’ that typically form in acid-dissolution experiments and have been described from some natural weathering contexts. The weathering products comprise sub-urn thick crystallites of an Fe-K aluminosilicate, probably smectite, that have grown within an amorphous and probably organic-rich matrix. There is also evidence for crystallization of clays having been mediated by fungal hyphae. Coatings formed within Glen Feshie soils after ∼1.1 ky are insufficiently continuous or impermeable to slow rates of fluid-feldspar reactions, but provide valuable insights into the complex weathering microenvironments on debris and microbe-covered mineral surfaces.

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Copyright

Corresponding author

Footnotes

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Present address: Institut für Mineralogie, Westfälische, Wilhelms-Universität Münster, Corrensstrasse 24, 48149 Münster, Germany

§

Present address: Department of Mineralogy, The Natural History Museum, London SW7 5BD, UK

Footnotes

References

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Bain, D.C., Mellor, A., Robertson-Rintoul, M.S.E. and Buckland, S.T. (1993) Variations in weathering processes and rates with time in a chronosequence of soils from Glen Feshie, Scotland. Geoderma, 57, 275293.
Banfield, J.F. and Barker, W.W. (1994) Direct observation of reactant-product interfaces formed in natural weathering of exsolved, defective amphibole to smectite: Evidence for episodic, isovolumetric reactions involving structural inheritance. Geochimica et Cosmochimica Ada, 58, 14191429.
Banfield, J.F. and Eggleton, R.A. (1990) Analytical transmission electron microscope studies of plagio-clase, muscovite and K-feldspar weathering. Clays and Clay Minerals, 38, 7789.
Banfield, J.F., Ferruzzi, G.G., Casey, W.H. and Westrich, H.R. (1995) HRTEM study comparing naturally and experimentally weathered pyroxenoids. Geochimica et Cosmochimica Ada, 59, 1931.
Berner, R.A. and Holdren, G.R. (1979) Mechanism of feldspar weathering. 2. Observations of feldspars from soils. Geochimica et Cosmochimica Ada, 43, 11731186.
Blum, A.E. (1994) Feldspars in weathering. Pp. 595–630 in: Feldspars and their Reactions (Parsons, I., editor), Kluwer, Dordrecht, The Netherlands.
Casey, W.H., Westrich, H.R., Massis, T., Banfield, J.F. and Arnold, GW. (1989) The surface of labradorite feldspar after acid hydrolysis. Chemical Geology, 78, 205218.
Eggleton, R.A. (1987) Noncrystalline Fe-Si-Al oxyhydr-oxides. Clays and Clay Minerals, 35, 2937.
Eggleton, R.A. and Buseck, P.R. (1980) High resolution electron microscopy of feldspar weathering. Clays and Clay Minerals, 28, 173178.
Heaney, P.J., Vicenzi, E.P., Giannuzzi, LA. and Livi, K.J.T. (2001) Focused ion beam milling: A method of site-specific sample extraction for microanalysis of Earth and planetary materials. American Mineralogist, 86, 10941099.
Hellmann, R., Eggleton, CM., Hochella, M.F. Jr. and Crerar, DA. (1990) The formation of leached layers on albite surfaces during dissolution under hydro-thermal conditions. Geochimica et Cosmochimica Ada, 54, 12671281.
Hodson, M.E. (2003) The influence of Fe-rich coatings on the dissolution of anorthite at pH 2.6. Geochimica et Cosmochimica Ada, 67, 33553363.
Hodson, M.E., Langan, S.J., Kennedy, F.M. and Bain, D.C. (1998) Variation in soil surface area in a chronosequence of soils from Glen Feshie, Scotland and its implications for mineral weathering rate calculations. Geoderma, 85, 118.
Kawano, M. and Tomita, K (1994) Growth of smectite from leached layer during experimental alteration of albite. Clays and Clay Minerals, 42, 717.
Kawano, M. and Tomita, K. (1996) Amorphous aluminium hydroxide formed at the earliest weathering stages of K-feldspar. Clays and Clay Minerals, 44, 672676.
Lee, M.R. and Smith, C.L. (2006) Scanning transmission electron microscopy using a SEM: Applications to mineralogy and petrology. Mineralogical Magazine, 70, 579590.
Lee, M.R., Bland, P.A. and Graham, G. (2003) Preparation of TEM samples by focused ion beam (FIB) techniques: applications to the study of clays and phyllosilicates in meteorites. Mineralogical Magazine, 67, 581592.
Lee, M.R., Brown, D.J., Smith, C.L., Hodson, M.E., MacKenzie, M. and Hellmann, R. (2007) Characterisation of mineral surfaces using FIB and TEM: A case study of naturally-weathered alkali feldspars. American Mineralogist, 92, 13831394.
Lee, M.R., Hodson, M.E., Brown, D.J., MacKenzie, M. and Smith, C.L. (2008) The composition and crystallinity of the near-surface regions of weathered alkali feldspars. Geochimica et Cosmochimica Ada, 72, 49624975.
Muir, I.J., Bancroft, G.M. and Nesbitt, H.W. (1989) Characteristics of altered labradorite surfaces by SIMS andXPS. Geochimica et Cosmochimica Acta, 53, 12351241.
Nugent, M.A., Brantley, S.L., Pantano, C.G. and Maurice, P.A. (1998) The influence of natural mineral coatings on feldspar weathering. Nature, 395, 588591.
Parham, W.E. (1969) Formation of halloysite from feldspar: low temperature artificial weathering versus natural weathering. Clays and Clay Minerals, 17, 1322.
Robertson-Rintoul, M.S.E. (1986) A quantitative soil-stratigraphic approach to the correlation and dating of post-glacial river terraces in Glen Feshie, western Cairngorms. Earth Surface Processes Landforms, 11, 605617.
Sanchez-Navas, A., Martin-Algarra, A. and Nieto, F. (1998) Bacterially-mediated authigenesis of clays in phosphate stromatolites. Sedimentology, 45, 519533.
Smith, C.L., Lee, M.R. and MacKenzie, M. (2006) New opportunities for nanomineralogy using FIB, STEM/ EDX and TEM. Microscopy Analysis, 111, 1720.
Tazaki, K. (1986) Observation of primitive clay precursors during microcline weathering. Contributions to Mineralogy and Petrology, 92, 8688.
Tazaki, K. and Fyfe, W.S. (1987) Primitive clay precursors formed on feldspar. Canadian Journal Earth Science, 24, 506527.
Velbel, M.A. (1993) Formation of protective surface layers during silicate mineral weathering under well leached oxidizing conditions. American Mineralogist, 78, 405414.
White, A.F. and Brantley, S.L. (2003) The effect of time on the weathering of silicate minerals: why do weathering rates differ in the laboratory and field? Chemical Geology, 202, 479506.
Wirth, R. (2004) Focused Ion Beam (FIB): A novel technology for advanced application of micro- and nanoanalysis in geosciences and applied mineralogy. European Journal of Mineralogy, 16, 863876.
Zhu, C, Veblen, D.R., Blum, A.E. and Chipera, SJ. (2006) Naturally weathered feldspar surfaces in the Navajo Sandstone aquifer, Black Mesa, Arizona: Electron microscopic characterization. Geochimica et Cosmochimica Acta, 65, 34593474.

Keywords

Weathering microenvironments on feldspar surfaces: implications for understanding fluid-mineral reactions in soils

  • M. R. Lee (a1), D. J. Brown (a1), M. E. Hodson (a2), M. Mackenzie (a3) and C. L. Smith (a1)...

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