Hostname: page-component-8448b6f56d-mp689 Total loading time: 0 Render date: 2024-04-23T09:32:48.379Z Has data issue: false hasContentIssue false
  • English
  • Français

Saponite, Corrensite and Chlorite-Saponite Mixed-Layers in the Sancerre-Couy Deep Drill-Hole (France)

Published online by Cambridge University Press:  09 July 2018

D. Beaufort  and
A. Meunier
D. Beaufort
Affiliation:
Laboratoire de Pétrologie des Altérations Hydrothermales, URA 721 CNRS, Université Poitiers, 40 avenue du Recteur Pineau, 86022 Poitiers Cedex, France
A. Meunier
Affiliation:
Laboratoire de Pétrologie des Altérations Hydrothermales, URA 721 CNRS, Université Poitiers, 40 avenue du Recteur Pineau, 86022 Poitiers Cedex, France
Get access Rights & Permissions [Opens in a new window]

Abstract

The clay deposits in fractures of the metamorphic basement under the Paris Basin sedimentary formations at Sancerre-Couy (France) are composed of trioctahedral species which are exceptionally well crystallized. Three samples were chosen in order to study the chemical composition of 100% expandable saponite, 50% expandable corrensite and 10% expandable chlorite-saponite mixed-layer mineral C90–S10 Two sets of microchemical analyses were performed in order to determine the variations of the composition on large and small numbers of particles. X-ray diffraction (XRD) and Mössbauer spectrometry were performed on purified samples.

The mathematical decomposition of Si, Al and Mg histograms established from microanalyses of a large number of crystals of saponite, corrensite and C90–S10 evidences bimodal populations. The total Fe content of the three species is unimodal whatever the chemical composition of the surrounding rock and the Fe2+/Fe3+ ratio. The structural formulae established from a large number of microanalyses of a few particles show that there are no parental relationships between saponite, corrensite and C90–S10. The expandable layer of corrensite is characterized by a high charge. It is proposed that the tetrahedral sheets adjacent to the brucitic sheet and the exchangeable interlayer in a 2 : 1 unit are identical in corrensite.

Type
Research Article
Information
Clay Minerals , Volume 29 , Issue 1 , March 1994 , pp. 47 - 61
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1994

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

April, R.H. (1980) Regularly interstratified chlorite-vermi- culite in contact metamorphosed red beds, Newark Group, Connecticut Valley. Clays Clay Miner. 28,1–11.CrossRefGoogle Scholar
April, R.H. (1981) Trioctahedral smectite and interstratified chlorite/smectite in Jurassic strata of the Connecticut Valley. Clays Clay Miner. 29, 31–39.Google Scholar
Bailey, S.W. (1982) Nomenclature for regular interstratifications. Am. Miner.. 67, 394–398.Google Scholar
Beaufort, D., Meunier, A., Thomassin, J.H. & Fouillac, A.M. (1991) Corrensite, chlorite/smectite mixed layered minerals and saponite in the metamorphic basement of the Basin of Paris (France). Proc. 7th Euroclay Conf., Dresden, 65–69.Google Scholar
Bodine, M.W. & Madsen, B.M. (1987) Mixed-layer chlorites, smectites from a Pennsylvanian evaporite cycle, Grand Country, Utha. Proc. Int. Clay Conf., Denver, 85–93.Google Scholar
Boulègue, J., Benedetti, M., Gauthier, B. & Bosch, B. (1990) Les fluides dans le socle du sondage GPF Sancerre-Couy. Bull. Soc. Geol. Franc.. 8, 787–795.Google Scholar
Chang, H.K., Mackenzie, F.T. & Schoonmaker, J. (1986) Comparison between the diagenesis of dioctahedral and trioctahedral smectite, Brasilian offshire basins. Clays Clay Miner. 34, 407–423.Google Scholar
Fouillac, A.M. & Beaufort, D. (1991) Etude minéralogi- que et isotopique (13C, 18O) des carbonates néoformes dans le sandage profond de Sancerre-Couy (France). Bull. Soc. Geol. Franc.. 162, 939–945.Google Scholar
Fouillac, A.M. & Beaufort, D. (1992) A stable isotope study of clay minerals from the Sancerre Couy deep drill hole, Paris Basin (France). Proc. 7th Water-Rock Interaction, Park City, Utha v2, 1227-1229.Google Scholar
Goodman, B.A. & Bain, D.C. (1979) Mössbauer spectra of chlorites and their decomposition products. Proc. Int. Clay Conf. Oxford, 65–74.Google Scholar
Hower, J. & Mowatt, T.C. (1966) The mineralogy of illites and mixed-layer illite/montmorillonites. Am. Miner.. 51, 825–854.Google Scholar
Inoue, A. (1985) Chemistry of corrensite: a trend in composition of trioctahedral chlorite/smectite during diagenesis. J. Coll. Arts Sci., Chiba Univ. B-18, 69–82.Google Scholar
Inoue, A. (1987) Conversion of smectite to chlorite by hydrothermal diagenetic alterations, Flokuroku Kuroko mineralization area, Northeast Japan. Proc. Int. Clay Conf, Denver, 158–164.Google Scholar
Inoue, A. & Utada, M. (1991) Smectite-to-chlorite transformation in thermally metamorphosed volcanoclastic rocks in the Kamikita area, northern Honshu, Japan. Am. Miner.. 76, 628–640.Google Scholar
Kristmansdottir, H. (1979) Alteration of basaltic rocks by hydrothermal activity at 100-300°C. Proc. 6th Int. Clay Conf. Oxford, 359–367.Google Scholar
Lanson, B. & Besson, G. (1992) Characterization of the end of smectite-to-illite transformation: decomposition of X- ray patterns. Clays Clay Miner. 40, 40–52.Google Scholar
Meunier, A., Inoue, A. & Beaufort, D. (1991) Chemio- graphic analysis of trioctahedral smectite-to-chlorite conversion series from the Ohyu Caldera, Japan. Clays Clay Miner. 39, 409–415.Google Scholar
Reynolds, R.C. Jr. (1985) NEWMOD a Computer Program for the Calculation of One-Dimensional diffraction Patterns for Mixed-Layered Clays. R. C. Reynolds, 8 Brook Rd., Hanover, New Hampshire 03755, USA.Google Scholar
Reynolds, R.C. Jr. (1988) Mixed-layer chlorite minerals. Pp. 601–609 in: Hydrous Phyllosilicates (Exclusive of Micas). Reviews in Mineralogy, 19 (S. W. Bailey, editor) Mineral. Soc. Amer., Washington, DC.Google Scholar
Shau, Y.H., Peacor, D.R. & Essene, E.J. (1990) Corrensite and mixed-layer chlorite/corrensite in metabasalts from northern Taiwan: TEM/AEM, EMPA, XRD and optical studies. Contrib. Mineral. Petrol.. 105, 123–142.Google Scholar
Suquet, J., Malard, C., Copin, E. & Pezerat, H. (1981) Variation du paramétre b et de la distance basale d001 dans une serie de saponite à charge croissante: 1. Etats hydrates. Clay Miner.. 16, 53–67.Google Scholar
Velde, B (1977) Clays and Clay Minerals in Natural and Synthetic Systems. Elsevier, Amsterdam.Google Scholar