Hostname: page-component-cd9895bd7-jn8rn Total loading time: 0 Render date: 2024-12-27T12:01:05.686Z Has data issue: false hasContentIssue false

Chemiographic Analysis of Trioctahedral Smectite-to-Chlorite Conversion Series from the Ohyu Caldera, Japan

Published online by Cambridge University Press:  02 April 2024

A. Meunier
Affiliation:
Laboratoire de Pétrologie des Altérations Hydrothermales URA 721 CNRS., Université de Poitiers., 40, avenue du Recteur Pineau., 86022 Poitiers Cedex., France
A. Inoue
Affiliation:
Geological Institute, College of Arts and Sciences, Chiba University, Chiba 260, Japan
D. Beaufort
Affiliation:
Laboratoire de Pétrologie des Altérations Hydrothermales URA 721 CNRS., Université de Poitiers., 40, avenue du Recteur Pineau., 86022 Poitiers Cedex., France
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

The chemical compositions of chlorite-smectite mixed-layered minerals (C/S) from the Ohyu caldera (Inoue, 1985) are analyzed using M+-4Si-3R2+ diagrams. The assumed original saponite has the following composition: Si3.54Al0.46O10Al0.173Fe2+1.385Mg1.295Mn0.02(OH)2M+0.56. Random C/S minerals (100 to 80% expandable layers) are interpreted as an interstratification of the starting 2:1 smectite layer with a A1XR2+3−x interlayer. The 2:1 smectite layer charge remains constant but Ca, Na, K cations are replaced by a Al-R2+ complex ion. The brucitic layer (produced by the polymerization of the complex ions) and the 2:1 smectite layer form a 14 Å non-expandable phase having a composition different from a true chlorite.

The true chlorite layers first appear in the ordered (corrensite) phase composed of a high charge saponite: Si3.35A10.65O10R2+3(OH)2M+0.65 and an octahedral vacancy-free chlorite Si2.90A11.10O10Al1.10R2+4.90(OH)8. The recrystallization of the original trioctahedral smectite into a high-charge saponite decreases the b-dimension difference with the chlorite component.

From these data, it is suggested that the trioctahedral smectite-to-chlorite conversion is controlled by three reactions: 1. fixation and polymerization of Al-R2+ complex ions in the interlayer region of the original smectite producing a 14 Å non-expandable phase (the interlayering of this phase with the original smectite gives the randomly interstratified C/S mineral. 2. dissolution of these random mixed-layered minerals and precipitation of corrensite. 3. dissolution of corrensite and growth of Fe-rich chlorite.

Type
Research Article
Copyright
Copyright © 1991, The Clay Minerals Society

References

April, R. H., 1980 Regularly interstratifled chlorite-vermiculite in contact metamorphosed red beds, Newark Group, Connecticut Valley Clays & Clay Minerals 28 111.CrossRefGoogle Scholar
April, R. H., 1981 Trioctahedral smectite and interstrati-fied chlorite/smectite in Jurassic strata of the Connecticut Valley Clays & Clay Minerals 29 3139.CrossRefGoogle Scholar
Bailey, S. W., 1988 Chlorites: structures and crystal chemistry Reviews in Mineralogy 19 347403.Google Scholar
Bodine, M. W., Hausen, D. M. and Kopp, O. C., 1985 Clay mineralogy of insoluble residues in marine evaporites Mineralogy V: Applications to the Mineral Industry New York Amer. Inst. Min. Metall. Petrol. Eng. 133156.Google Scholar
Bodine, M. W., Madsen, B. M., Schultz, L. G., van Olphen, H. and Mumpton, F. A., 1987 Mixed-layer chlorite/smectite from a Pennsylvanian evaporite cycle, Grand County, Utah Proc. Int. Clay Conf., Denver, 1985 Bloomington, Indiana The Clay Minerals Society 8593.Google Scholar
Brigatti, M. F. and Poppi, L., 1984 Crystal chemistry of corrensite: A review Clays & Clay Minerals 32 391399.CrossRefGoogle Scholar
Chang, H. K., Mackenzie, F. T. and Schoonmaker, J., 1986 Comparisons between the diagenesis of dioctahedral and trioctahedral smectite, Brasilian offshore basins Clays & Clay Minerals 34 407423.CrossRefGoogle Scholar
Deer, W. A., Howie, R. A. and Zussman, J., 1971 Rock-Forming Minerals, Vol. 3. Sheet Silicates: London Longmans.Google Scholar
de la Calle, C. and Suquet, H., 1988 Vermiculite Reviews in Mineralogy 19 455496.Google Scholar
Elderfield, H. and Riley, Chester, , 1976 Hydrogenous material in marine sediments; excluding manganese nodules Chemical oceanography, Vol. 5 New York Academic Press 137208.Google Scholar
Güven, N., 1988 Smectites Reviews in Mineralogy 19 497559.Google Scholar
Inoue, A., 1985 Chemistry of corrensite: a trend in composition of trioctahedral chlorite/smectite during diagenesis Jour. Coll. Arts & Sci., Chiba Univ. B–18 6982.Google Scholar
Inoue, A., Schultz, L. G., Olphen, H. v. and Mumpton, F. A., 1987 Conversion of smectite to chlorite by hydrothermal diagenetic alterations, Hokuroku Kuroko mineralization area, Northeast Japan Proc. Int. Clay Conf., Denver, 1985 Bloomington, Indiana The Clay Minerals Society 158164.Google Scholar
Inoue, A., Utada, M., Nagata, H. and Watanabe, T., 1984 Conversion of trioctahedral smectite to interstratified chlorite/smectite in Pliocene acidic pyroclastic sediments of the Ohyu district, Akita Prefecture, Japan Clay Sci. 6 103106.Google Scholar
Kristmannsdottir, H., Mortland, M. M. and Farmer, V. C., 1979 Alteration of basaltic rocks by hydrothermal activity at 100–300°C Proc. 6th Int. Clay Conf. Amsterdam Elsevier 359367.Google Scholar
Kristmannsdottir, H., Rona, P. A., Böstrom, K., Laubier, L. and Smith, K. L. Jr., 1983 Chemical evidence from Icelandic geothermal systems as compared to submarine geo-thermal systems Hydrothermal processes at Seafloor Spreading Centers New York Plenum 291301.CrossRefGoogle Scholar
Meunier, A. and Velde, B., 1989 Solid solutions in I/S mixed-layer minerals and illite Amer. Mineral. 74 11061112.Google Scholar
Reynolds, R. C., 1988 Mixed-layer chlorite minerals Reviews in Mineralogy 19 601629.Google Scholar
Suquet, H. M. C. Copin, E. and Pezerat, H., 1981 Variation du paramètre b et de la distance basale d001 dans une série de saponites à charge croissante: 1. Etats hydratés Clay Miner. 16 5367.CrossRefGoogle Scholar
Velde, B., 1977 Clays and Clay Minerals in Natural and Synthetic Systems Amsterdam Elsevier.Google Scholar
Yen-Hong Shau, Peacor, D. R. and Essene, E. J., 1990 Corrensite and mixed-layer chlorite/corrensite in metaba-salts from northern Taiwan: TEM/AEM, EMPA, XRD, and optical studies Contrib. Mineral. Petrol. 105 123142.CrossRefGoogle Scholar