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Diagenetic Illite-Chlorite Assemblages in Arenites. II. Thermodynamic Relations

Published online by Cambridge University Press:  28 February 2024

P. Aagaard  and
J. S. Jahren
P. Aagaard
Affiliation:
Department of Geology, University of Oslo, P.O. Box 1047 Blindern, 0316, Oslo 3, Norway
J. S. Jahren
Affiliation:
Department of Geology, University of Oslo, P.O. Box 1047 Blindern, 0316, Oslo 3, Norway
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Abstract

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The internal equilibrium status among chlorite-illite pairs has been evaluated through coupled substitution reactions. Compositional data of chlorites and illites from arenites at present burial temperatures between 90° and 180°C have been used to calculate end member activities and reaction quotients of the combined Tschermak reaction:

Muscovite+Clinochlore=MgAl−celadonite+Amesite.

The reaction quotient data in the 90° to 180°C temperature range have then been compared with the equilibrium curve for the same reaction, and found to be in reasonable agreement. This indicates that chlorites and illites in these arenites grow at near equilibrium conditions.

The data set has also been compared with chlorite-illite pairs from hydrothermally altered arenites of the Salton Sea area. For chlorite-illite containing assemblages, these data agree well with the diagenetic ones. The introduction of biotite at higher temperatures alters with the iron-magnesium distribution and breaks down the substitution relationship between chlorite and illite.

The model predicts an increasing stability of muscovite and clinochlore components with increasing temperature, while celadonite and amesite would be stabilized with increasing pressure. This is consistent with high pressure occurrences of phengite. However, at the low pressure region of diagenesis and hydrothermal alteration, the temperature effect is dominant.

Keywords

ArenitesDiagenesisIllite/ChloriteTschermak reaction
Type
Research Article
Information
Clays and Clay Minerals , Volume 40 , Issue 5 , October 1992 , pp. 547 - 554
Copyright
Copyright © 1992, The Clay Minerals Society

References

Aagaard, P. and Helgeson, H. C., 1983 Activity/composition relations among silicates and aqueous solutions: II. Chemical and thermodynamic consequences of ideal mixing of atoms on homological sites in montmorillonites, illites, and mixed-layer clays Clays & Clay Minerals 51 207 – 217 10.1346/CCMN.1983.0310306.CrossRefGoogle Scholar
Aagaard, P., Egeberg, P. K. and Jahren, J. S., 1992 North Sea clastic diagenesis and formation water constraints Water-Rock Interaction 2 1147 – 1152.Google Scholar
Bishop, B. P. and Bird, D. K., 1987 Variation in sericite compositions from fracture zones within the Coso Hot Springs geothermal system Geochim. Cosmochim. Acta 51 1245 – 1256 10.1016/0016-7037(87)90216-X.CrossRefGoogle Scholar
Cathelineau, M., 1988 Cation site occupancy in chlorites and illites as a function of temperature Clay Miner. 23 471 – 485 10.1180/claymin.1988.023.4.13.CrossRefGoogle Scholar
Cathelineau, M. and Izquirdo, G., 1988 Temperature-composition relationships of authigenic micaceous minerals in the Los Azufres geothermal system Contrib. Mineral. Petr. 100 418 – 428 10.1007/BF00371372.CrossRefGoogle Scholar
Cathelineau, M. and Neiva, D., 1985 A chlorite solid solution geothermometer. The Los Azufres (Mexico) geothermal system Contrib. Mineral. Petr. 91 235 – 244 10.1007/BF00413350.CrossRefGoogle Scholar
Curtis, C. D., Hughes, C. R., Whiteman, J. A. and Whittle, C. K., 1985 Compositional variations within some sedimentary chlorites and some comments on their origin Mineral. Mag. 49 375 – 386 10.1180/minmag.1985.049.352.08.CrossRefGoogle Scholar
Egeberg, P. K. and Aagaard, P., 1992 Formation water chemistry in relation to the stability of detrital and authigenic minerals in clastic reservoirs from offshore Norway Marine Petr. Geol. .Google Scholar
Fawcett, J. J. and Yoder, H. S. Jr., 1966 Phase relations of chlorites in the system MgO-Al2O3-SiO2-H2O Amer. Mineral. 51 353 – 380.Google Scholar
Guidotti, C. V., 1984 Micas in metamorphic rocks Micas, Reviews in Mineralogy 13 357 – 467.Google Scholar
Helgeson, H. C. and Aagaard, P., 1985 Activity/composition relations among silicates and aqueous solutions. I. Thermodynamics of intrasite mixing and substitutional order/disorder in minerals Amer. J. Sci. 285 769 – 844 10.2475/ajs.285.9.769.CrossRefGoogle Scholar
Helgeson, H. C., Delany, J. M., Nesbitt, H. W. and Bird, D. K., 1978 Summary and critique of the thermodynamic properties of rock forming minerals Amer. J. Sci. 267 729 – 804 10.2475/ajs.267.7.729.CrossRefGoogle Scholar
Hillier, S. and Velde, B., 1991 Octahedral occupancy and the chemical composition of diagenetic (low-temperature) chlorites Clay Miner. 26 149 – 168 10.1180/claymin.1991.026.2.01.CrossRefGoogle Scholar
Jahren, J. S., 1991 Evidence of Ostwald ripening related recrystallization of chlorites from reservoir rocks offshore Norway Clay Miner. 26 169 – 178 10.1180/claymin.1991.026.2.02.CrossRefGoogle Scholar
Jahren, J. S. and Aagaard, P., 1989 Compositional variations in diagenetic chlorites and illites, and relationships with formation-water chemistry Clay Miner. 24 157 – 170 10.1180/claymin.1989.024.2.04.CrossRefGoogle Scholar
Jahren, J. S. and Aagaard, P., 1992 Diagenetic illite-chlorite assemblages in arenites. I. Chemical evolution Clays & Clay Minerals .CrossRefGoogle Scholar
Jenkins, D. M. and Chernosky, J. V., 1986 Phase equilibria and crystallo-chemical properties of Mg-chlorite Amer. Mineral. 71 924 – 936.Google Scholar
Johnson, J. W., Oelkers, E. H. and Helgeson, H. C., 1992 SUPCRT92: A Software Package for Calculating the Standard Molal Thermodynamic Properties of Minerals, Gases, Aqueous Species, and Reactions from 1 to 5000 bars and 0° to 1000°C Computers and Geosciences .CrossRefGoogle Scholar
Kotov, N. V., 1974 Muscovite-chlorite paleothermometer Dokl. Akad. Nauk SSSR 222 701 – 704.Google Scholar
McDowell, S. D. and Elders, W. A., 1980 Authigenic layer silicated minerals in borehole Elmore 1, Salton Sea Geothermal field, California, USA Contrib. Mineral. Petr. 74 293 – 310 10.1007/BF00371699.CrossRefGoogle Scholar
Roots, M., 1991 Molar volume and pressure-dependent non-ideality of the clinochlore-amesite solid solution Uppsala, Research Report no. 65 Uppsala University, Department of Mineralogy and Petrology.Google Scholar
Smith, J. T. and Ehrenberg, S. N., 1989 Correlation of carbon dioxide abundance with temperature in clastic hydrocarbon reservoirs: Relationship to inorganic chemical equilibrium Marine Petr. Geol. 6 129 – 135 10.1016/0264-8172(89)90016-0.CrossRefGoogle Scholar
Stoessel, R. K., 1979 Refinements in a site-mixing model for illites Geochim. Cosmochim. Acta 43 1151 – 1159 10.1016/0016-7037(79)90108-X.CrossRefGoogle Scholar
Stoessel, R. K., 1981 A regular solution site-mixing model for illites: Local electrostatic balance and the quasichemical approximation Geochim. Cosmochim. Acta 45 1733 – 1741 10.1016/0016-7037(81)90007-7.CrossRefGoogle Scholar
Stoessel, R. K., 1984 Regular solution site-mixing model for chlorites Clays & Clay Minerals 32 205 – 212 10.1346/CCMN.1984.0320308.CrossRefGoogle Scholar
Tardy, Y. and Fritz, B., 1981 An ideal solid solution model for calculating solubility of clay minerals Clay Miner. 16 361 – 373 10.1180/claymin.1981.016.4.05.CrossRefGoogle Scholar
Velde, B. and Medhioub, M., 1988 Approach to chemical equilibrium in diagenetic chlorites Contrib. Mineral. Petr. 98 122 – 127 10.1007/BF00371916.CrossRefGoogle Scholar
Walshe, J. L., 1986 A six-component chlorite solid solution model and conditions of chlorite formation in hydrothermal and geothermal systems Econ. Geol. 81 681 – 703 10.2113/gsecongeo.81.3.681.CrossRefGoogle Scholar
Wiewiora, A. and Weiss, Z., 1990 Crystallochemical classification of phyllosilicates based on the unified system of projection of chemical composition: II. The chlorite group Clay Miner. 25 83 – 92 10.1180/claymin.1990.025.1.09.CrossRefGoogle Scholar