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Illitization of Kaolinite: The Effect of Pressure on the Reaction Rate

Published online by Cambridge University Press:  01 January 2024

Marco Mantovani  and
Ana Isabel Becerro
Marco Mantovani*
Affiliation:
Instituto de Ciencia de Materiales, Departamento de Química Inorgánica (CSIC-US), c/ Américo Vespucio, 49, 41092 Sevilla, Spain
Ana Isabel Becerro
Affiliation:
Instituto de Ciencia de Materiales, Departamento de Química Inorgánica (CSIC-US), c/ Américo Vespucio, 49, 41092 Sevilla, Spain
*
* E-mail address of corresponding author: [email protected]
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Abstract

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Studies of the paragenesis of authigenic illite in arkosic sandstones of various regions and ages have revealed that the illitization of kaolinite is an important reaction accounting for the formation of authigenic illite in sandstones during burial diagenesis. The illitization of kaolinite takes place at an intermediate burial depth of 3–4 km, where pressure can reach values of 100 MPa (≈ 1000 bars). The purpose of the present study was to analyze the effect of pressure on the rate of kaolinite illitization in alkaline conditions. Hydrothermal reactions were conducted on KGa-1b kaolinite in KOH solution at 300°C and under pressures of 500, 1000, and 3000 bars for 1 to 24 h. The visual examination of the X-ray diffraction (XRD) patterns indicated a notable influence of pressure on the reaction rate. Molar percentages of muscovite/illite formed at each time interval were calculated from the analysis of two diagnostic XRD peaks, representing the 060 reflections of kaolinite and muscovite/illite. The data were modeled to obtain the initial rate of conversion at each pressure. The results indicated that the initial rate of kaolinite to muscovite/illite conversion is one order of magnitude greater at 3000 bars than at 500 or 1000 bars. Comparison of these data with those in the literature show a faster conversion rate (several orders of magnitude) in an initially high-alkaline solution than in a near-neutral solution.

Keywords

Hydrothermal ReactionKaoliniteKOHMuscovite/illitePressureReaction RateXRD
Type
Article
Information
Clays and Clay Minerals , Volume 58 , Issue 6 , December 2010 , pp. 766 - 771
Copyright
Copyright © Clay Minerals Society 2010

References

Bailey, S.W., and Bailey, S.W., 1984 Crystal chemistry of the true micas Micas Washington, D.C. Reviews in Mineralogy, 13, Mineralogical Society of America 13–60 10.1515/9781501508820-006.CrossRefGoogle Scholar
Bauer, A., Velde, B., and Berger, G., 1998 Kaolinite transformation in high molar KOH solutions Applied Geochemistry 13 619–629 10.1016/S0883-2927(97)00094-2.CrossRefGoogle Scholar
Bjorlikke, K., 1980 Clastic diagenesis and basin evolution Revista del Instituto de Investigaciones Geologicas. Diputacion Provincial, Universidad de Barcelona 34 21–44.Google Scholar
Chermak, J.A., and Rimstidt, J.D., 1990 The hydrothermal transformation rate of kaolinite to muscovite/illite Geochimica et Cosmochimica Acta 54 2979–2990 10.1016/0016-7037(90)90115-2.CrossRefGoogle Scholar
Dutta, P.K., and Suttner, L.J., 1986 Alluvial sandstone composition and paleoclimate. II. Authigenic mineralogy Journal of Sedimentary Petrology 56 346–358.Google Scholar
Hancock, N.J., and Taylor, A.M., 1978 Clay minerals diagenesis and oil migration in the Middle Jurassic Brent Sand Formation Journal of the Geological Society of London 135 69–72 10.1144/gsjgs.135.1.0069.CrossRefGoogle Scholar
Huang, W.L., 1993 The formation of illitic clays from kaolinite in KOH solution from 225°C to 350°C Clays and Clay Minerals 41 645–654 10.1346/CCMN.1993.0410602.Google Scholar
Seeman, U., 1979 Diagenetically formed interstitial clay minerals as a factor in Rotliegend sandstone reservoir quality in the North Sea Journal of Petroleum Geology 1 55–62 10.1111/j.1747-5457.1979.tb00619.x.CrossRefGoogle Scholar
Sommer, F., 1978 Diagenesis of Jurassic sandstones in the Vicking Graben Journal of the Geological Society of London 125 63–67 10.1144/gsjgs.135.1.0063.CrossRefGoogle Scholar
Sonneveld, E.J., and Delhez, R., 1996 ProFit 1.0c The Netherlands Philips Electronics NV.Google Scholar
Velde, B., 1965 Experimental determination of muscovite polymorph stabilities American Mineralogist 50 436–449.Google Scholar