Hostname: page-component-7c8c6479df-fqc5m Total loading time: 0 Render date: 2024-03-27T12:38:00.382Z Has data issue: false hasContentIssue false

Chlorite Geothermometry?—Contamination and Apparent Octahedral Vacancies

Published online by Cambridge University Press:  28 February 2024

Wei-Teh Jiang
Affiliation:
Departments of Geology and Chemistry, Arizona State University, Tempe, Arizona 85287-1404
Donald R. Peacor
Affiliation:
Department of Geological Sciences, The University of Michigan, Ann Arbor, Michigan 48109-1063
Peter R. Buseck
Affiliation:
Departments of Geology and Chemistry, Arizona State University, Tempe, Arizona 85287-1404

Abstract

The large contents of octahedral vacancies in published formulae of chlorite from hydrothermal systems and clastic sequences are shown to be largely caused by inclusion of other minerals. Verification is provided by analytical electron microscope (AEM) analyses of chlorite in pelitic rocks from the Gaspé Peninsula, Quebec and the Gulf Coast, Texas. The Gaspé chlorite occurs as discrete crystals locally coexisting with corrensite, and the Gulf Coast chlorite is free of mixed layers other than local serpentine-like 7-Å layers. Unlike most electron microprobe analyses (EMPA), but like other AEM analyses, the reported chlorite formulae do not have significant octahedral vacancies, are not Si-rich and (Fe + Mg)-poor relative to classic metamorphic chlorite, and have nearly equal amounts of tetrahedral and octahedral Al. The studied chlorites and those in metabasites and clastic rocks that could be positively identified as containing no or minimal mixed layering or submicroscopic intergrowths have little or no Ca or alkalis. In contrast, EMPA of chlorite reported for other clastic sequences show variable amounts of Na + K + 2Ca that exhibit a poorly defined positive correlation with the proportion of octahedral vacancies. The EMPA of chlorite from the Salton Sea and Los Azufres geothermal fields that were suggested to contain temperature-dependent amounts of tetrahedral Al (and thus used as “chlorite geothermometers”) show compositional characteristics similar to those reported for several saponite-chlorite transition series in metabasites.

Continuous increases in octahedral occupancy and tetrahedral Al with increasing metamorphic grade are attributed to decreases in abundance of mixed layers or fine-grained intergrown minerals that commonly occur as a result of increasing crystal size and homogeneity in prograde sequences. Use of “chlorite geothermometry” based on the proportion of apparent octahedral vacancies or tetrahedral Al is therefore unwarranted and leads to inaccurate temperature estimates.

Type
Research Article
Copyright
Copyright © 1994, Clay Minerals Society

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

Ahn, J. H., and Peacor, D. R.. 1985a . Transmission electron microscope study of diagenetic chlorite in Gulf Coast argillaceous sediments. Clays & Clay Miner. 33: 228236.CrossRefGoogle Scholar
Ahn, J. H., and Peacor, D. R.. Transmission electron microscope study of the diagenesis of kaolinite in Gulf Coast argillaceous sediments. In Proceedings of the International Clay Conference, Denver, 1985. Schultz, L. G., Olphen, H. van, and Mumpton, A., 1985b eds. Bloomington, Indiana: The Clay Minerals Society, 151157.Google Scholar
Bailey, S. W., 1988. Chlorites: Structures and crystal chemistry. In Hydrous Phyllosilicates (Exclusive of Micas), Reviews in Mineralogy, Vol. 19. Bailey, S. W., ed. Washington D.C.: Mineralogical Society of America, 347403.CrossRefGoogle Scholar
Beiersdorfer, R. E., 1993. Metamorphism of a late Jurassic volcano-plutonic arc, northern California, USA. J. Metamorphic Geol. 11: 415428.CrossRefGoogle Scholar
Bettison, L. A., and Schiffman, P.. 1988 . Compositional and structural variations of phyllosilicates from the Point Sal ophiolite, California. Amer. Mineral. 73: 6276.Google Scholar
Bettison-Varga, L., Mackinnon, I. D. R., and Schiffman, P.. 1991 . Integrated TEM, XRD, and electron microprobe investigation of mixed-layer chlorite-smectite from the Point Sal ophiolite, California. J. Metamorphic Geol. 9: 697710.CrossRefGoogle Scholar
Bevins, R. E., Robinson, D., and Rowbotham, G.. 1991 . Compositional variations in mafic phyllosilicates from regional metabasites and application of the chlorite geothermometer. J. Metamorphic Geol. 9: 711721.CrossRefGoogle Scholar
Black, P. M., 1975. Mineralogy of New Caledonia metamorphic rocks: IV. Sheet silicates from the Ouégoa District. Contrib. Mineral. Petrol. 49: 269284.CrossRefGoogle Scholar
Boles, J. R., and Franks, S. G.. 1979 . Clay Diagenesis in Wilcox sandstones of southwest Texas: Implications of smectite diagenesis on sandstone cementation. J. Sediment. Petrol. 49: 5570.Google Scholar
Burton, J. H., Krinsley, D. H., and Pye, K.. 1987 . Authigenesis of kaolinite and chlorite in Texas Gulf Coast sediments. Clays & Clay Miner. 35: 291296.CrossRefGoogle Scholar
Cashman, K. V., and Ferry, J. M.. 1988 . Crystal size distribution (CSD) in rocks and the kinetics and dynamics of crystallization. III. Metamorphic crystallization. Contrib. Mineral. Petrol. 99: 401415.CrossRefGoogle Scholar
Cathelineau, M., 1988. Cation site occupancy in chlorites and illites as a function of temperature. Clay Miner. 23: 471485.CrossRefGoogle Scholar
Cathelineau, M., and Nieva, D.. 1985 . A chlorite solid solution geothermometer. The Los Azufres (Mexico) geothermal system. Contrib. Mineral. Petrol. 91: 235244.CrossRefGoogle Scholar
Cavarretta, G., Gianelli, G., and Puxeddu, M.. 1982 . Formation of authigenic minerals and their use as indicators of the physiochemical parameters of the fluid in the Larderello-Travalegeothermal field. Econ. Geol. 77: 10711084.CrossRefGoogle Scholar
Cooper, A. F., 1972. Progressive metamorphism of metabasic rocks from the Haast Schist Group of southern New Zealand. J. Petrol. 13: 457492.CrossRefGoogle Scholar
Curtis, C. D., Hughes, C. R., Whiteman, J. A., and Whittle, C. K.. 1985 . Compositional variation within some sedimentary chlorites and some comments on their origin. Mineral. Mag. 49: 375386.CrossRefGoogle Scholar
Curtis, C. D., Ireland, B. J., Whiteman, J. A., Mulvaney, R., and Whittle, C. K.. 1984 . Authigenic chlorites: Problems with chemical analysis and structural formula calculation. Clay Miner. 19: 471481.CrossRefGoogle Scholar
de Caritat, P., Hutcheon, I., and Walshe, J. L.. 1993 . Chlorite geothermometry: A review. Clays & Clay Miner. 41: 219239.CrossRefGoogle Scholar
Eberl, D. D., Srodon, J., Kralik, M., Taylor, B. E., and Peterman, Z. E.. 1990 . Ostwald ripening of clays and metamorphic minerals. Science 248: 474477.CrossRefGoogle Scholar
Foster, M. D., 1962. Interpretation of the composition and a classification of the chlorites. U. S. Geol. Surv. Prof. Paper 414–A: 133.Google Scholar
Freed, R. L., 1982. Clay mineralogy and depositional history of Frio Formation in two geopressured wells, Brazoria County, Texas. Gulf Coast Assoc. Geol. Soc. Trans. 32: 459463.Google Scholar
Freed, R. L., and Peacor, D. R.. 1989 . Variability in temperature of the smectite/illite reaction in Gulf Coast sediments. Clay Miner. 24: 171180.CrossRefGoogle Scholar
Gills, K. M., and Thompson, G.. 1993 . Metabasalts from the Mid-Atlantic Ridge: New insights into hydrothermal systems in slow-spreading crust. Contrib. Mineral. Petrol. 113: 502523.CrossRefGoogle Scholar
Gustin, M. S., 1990. Stratigraphy and alteration of the host rocks, United Verde massive sulfide deposit, Jerome, Arizona. Econ. Geol. 85: 2949.CrossRefGoogle Scholar
Hillier, S., and Velde, B.. 1991 . Octahedral occupancy and the chemical composition of diagenetic (low-temperature) chlorites. Clay Miner. 26: 149168.CrossRefGoogle Scholar
Hillier, S., and Velde, B.. 1992 . Chlorite interstratified with a 7 Å mineral: An example from offshore Norway and possible implications for the interpretation of the composition of diagenetic chlorites. Clay Miner. 27: 475486.CrossRefGoogle Scholar
Hower, J., Eslinger, E. V., Hower, M. E., and Perry, E. A. Jr. 1976 . Mechanism of burial metamorphism of argillaceous sediments: 1. Mineralogical and chemical evidence. Geol. Soc. Amer. Bull. 87: 725737.2.0.CO;2>CrossRefGoogle Scholar
Humphreys, B., Smith, S. A., and Strong, G. E.. 1989 . Authigenic chlorite in late Triassic sandstones from the Central Graben, North Sea. Clay Miner. 24: 427444.CrossRefGoogle 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: 6982.Google Scholar
Inoue, A., and Utada, M.. 1991 . Smectite-to-chlorite transformation in thermally metamorphosed volcanoclastic rocks in the Kamikita area, northern Honshu, Japan. Amer. Mineral. 76: 628640.Google Scholar
Jahren, J. S., 1991. Evidence of Ostwald ripening related recrystallization of chlorites from reservoir rocks offshore Norway. Clay Miner. 26: 169178.CrossRefGoogle Scholar
Jahren, J. S., and Aagaard, P.. 1992 . Diagenetic illite-chlorite assemblages in arenites. I. Chemical evolution. Clays & Clay Miner. 40: 540546.CrossRefGoogle Scholar
Jiang, W.-T., and Peacor, D. R.. 1991 . Transmission electron microscopic study of the kaolinitization of muscovite. Clays & Clay Miner. 39: 113.CrossRefGoogle Scholar
Jiang, W.-T., and Peacor, D. R.. 1994 . Prograde transitions of corrensite and chlorite in low-grade pelitic rocks from the Gaspé Peninsula, Quebec. Clays & Clay Miner. 42: 497517.CrossRefGoogle Scholar
Jiang, W.-T., Peacor, D. R., and Slack, J. F.. 1992 . Microstructures, mixed layering, and polymorphism of chlorite and retrograde berthierine in the Kidd Creek massive sulfide deposit, Ontario. Clays & Clay Miner. 40: 501514.CrossRefGoogle Scholar
Kranidiotis, P., and MacLean, W. H.. 1987 . Systematics of chlorite alteration at the Phelps Dodge massive sulfide deposit, Matagami, Quebec. Econ. Geol. 82: 18981911.CrossRefGoogle Scholar
Kreutzberger, M. E., and Peacor, D. R.. 1988 . Behavior of illite and chlorite during pressure solution of shaly limestone of the Kalkberg Formation, Catskill, New York. J. Struct. Geol. 10: 803811.CrossRefGoogle Scholar
Lee, J. H., Peacor, D. R., Lewis, D. D., and Wintsch, R. P.. 1984 . Chlorite-illite/muscovite interlayered and interstratified crystals: A TEM/STEM study. Contrib. Mineral. Petrol. 88: 372385.CrossRefGoogle Scholar
Li, G., Peacor, D. R., and Mauk, J. L.. 1994a . Clay minerals in the Proterozoic (1.1Ga) Lower Nonesuch Formation at White Pine, Michigan: A TEM and AEM study. Clays & Clay Miner. (in press).Google Scholar
Li, G., Peacor, D. R., Merriman, R. J., Roberts, B., and van der Pluijm, A.. 1994b . TEM and AEM constraints on the origin and significance of chlorite-mica stacks in slates: An example from central Wales, U.K. J. Struct. Geol. (in press).CrossRefGoogle Scholar
McDowell, S. D., and Elders, W. A.. 1980 . Authigenic layer silicate minerals in borehole Elmore 1, Salton Sea Geothermal Field, California, USA. Contrib. Mineral. Petrol. 74: 293310.CrossRefGoogle Scholar
Merriman, R. J., Roberts, B., and Peacor, D. R.. 1990 . A transmission electron microscope study of white mica crystallite size distribution in a mudstone to slate transitional sequence, North Wales, U.K. Contrib. Mineral. Petrol. 106: 2740.CrossRefGoogle Scholar
Peacor, D. R., 1992. Diagenesis and low-grade metamorphism of shales and slates. In Minerals and Reactions at the Atomic Scale: Transmission Electron Microscopy, Reviews in Mineralogy, Vol. 27. Buseck, P. R., ed. Washington D.C.: Mineralogical Society of America, 335380.CrossRefGoogle Scholar
Robinson, D., Bevins, R. E., and Rowbotham, G.. 1993 . The characterization of mafic phyllosilicates in low-grade metabasites from eastern North Greenland. Amer. Mineral. 78: 377390.Google Scholar
Schiffman, P., and Fridleifsson, G. O.. 1991 . The smectitechlorite transition in drillhole NJ-15, Nesjavellir geothermal field, Iceland: XRD, BSE and electron microprobe investigations. J. Metamorphic Geol. 9: 679696.CrossRefGoogle Scholar
Shau, Y.-H., and Peacor, D. R.. 1992 . Phyllosilicates in hydrothermally altered basalts from DSDP hole 504B, leg 83—ATEM and AEM study. Contrib. Mineral. Petrol. 112: 119133.CrossRefGoogle Scholar
Shau, Y.-H., Peacor, D. R., and Essene, E. J.. 1990 . Corrensite and mixed-layer chlorite/corrensite in metabasalt from northern Taiwan: TEM/AEM, EMPA, XRD, and optical studies. Contrib. Mineral. Petrol. 105: 123142.CrossRefGoogle Scholar
Shirozu, H., 1978. Chlorite minerals. In Clays and Clay Minerals of Japan. Sudo, T., and Shimoda, S., eds. Amsterdam: Elsevier, 243264.CrossRefGoogle Scholar
Velde, B., Moutaouakkil, N. El, and Iijima, A.. 1991 . Compositional homogeneity in low-temperature chlorites. Contrib. Mineral. Petrol. 107: 2126.CrossRefGoogle Scholar
Walshe, J. L., 1986. A six-component chlorite solid solution model and the conditions of chlorite formation in hydrothermal and geothermal systems. Econ. Geol. 81: 681703.CrossRefGoogle Scholar
Warren, E. A., and Ransom, B.. 1992 . The influence of analytical error upon the interpretation of chemical variations in clay minerals. Clay Miner. 27: 193209.CrossRefGoogle Scholar
Whittle, C. K., 1986. Comparison of sedimentary chlorite compositions by X-ray diffraction and analytical TEM. Clay Miner. 21: 937947.CrossRefGoogle Scholar
Wiewióra, A., and Weiss, Z.. 1990 . Crystallographical classifications of phyllosilicates based on the unified system of projection of chemical composition: II. The chlorite group. Clay Miner. 25: 8392.CrossRefGoogle Scholar
Williams, D. B., Goldstein, J. I., and Fiori, C. E.. Principles of X-ray energy-dispersive spectrometry in the analytical electron microscope. In Principles of Analytical Electron Microscopy. Joy, D. C., Romig, A. D. Jr., and Goldstein, J. I., 1989 eds. New York: Plenum Press, 123154.Google Scholar
Yau, Y.-C., Peacor, D. R., Beane, R. E., Essene, E. J., and McDowell, S. D.. 1988 . Microstructures, formation mechanisms, and depth zoning of phyllosilicates in geothermally altered shales, Salton Sea, California. Clays & Clay Miner. 36: 110.Google Scholar
Zheng, H., and Bailey, S. W.. 1989 . Structures of intergrown triclinic and monoclinic IIb chlorites from Kenya. Clays & Clay Miner. 37: 308316.CrossRefGoogle Scholar