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Chlorites in a spectrum of igneous rocks: mineral chemistry and paragenesis

Published online by Cambridge University Press:  05 July 2018

Abdel-Fattah M. Abdel-Rahman
Abdel-Fattah M. Abdel-Rahman*
Affiliation:
Department of Geology, Concordia University, 7141 Sherbrooke Str. West, Montreal, Quebec, Canada H4B 1R6
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Abstract

The chlorite data presented are from four igneous complexes covering the compositional spectrum of igneous rocks (gabbro to granite) of orogenic and anorogenic settings. The four igneous complexes are; early orogenic gabbro-diorite-tonalite (D-T) suite, late orogenic granodiorite-adamellite (G-A) suite (both are calc-alkaline suites), high-alumina trondhjemite (TR), and anorogenic peralkaline granite (PGR).

Chlorites in these igneous rocks show characteristic compositional fields. The Mg vs Fe plot provides the best discriminant, as data points define three compositionally different groups. Phases in the PGR are Fe-rich, siliceous, interlayered chlorite-smectite (Fe/Mg = 8.6), and differ significantly from those in the calc-alkaline D-T and G-A rocks which are Mg-rich chlorites (Fe/Mg = 0.6–0.8). The X-ray diffraction data for the peralkaline granite samples show superlattice reflections at approximately 31 Å (air-dried) and 34 Å (ethylene glycollated), thus suggesting the presence of an expandable (smectite-like) component in this interlayered (chlorite-smectite) phyllosilicate phase. Chlorites in the peraluminous TR rocks contain Fe/Mg values intermediate between the other two types (Fe/Mg = 1.3). Tetrahedral Al (AlZ) values are remarkably low (0–0.5) in phyllosilicates in the PGR, but vary from 1.9–2.5 in chlorites from the other suites. Yet, these chlorite groups with their generally low AlZ values are distinct from the more stable (type IIb) metamorphic chlorites. Sedimentary chlorites are somewhat similar, in their low AlZ values and metastable structural type, to chlorites in igneous rocks.

In the calc-alkaline rocks, chlorite may have been formed at the expense of both biotite [biotite + 3M + 3H2O = chlorite + A], and calcic amphibole [2 Ca-amphibole + 6H2O + 5O2 + 1.8Al = 1 chlorite + 8SiO2 + A], where M = Fe, Mg, Al, and A = K, Na, Ca. The alteration of alkali amphibole in the peralkaline rocks may have produced interlayered chlorite-smectite via this reaction; [1 Na-amphibole + 7H2O + 2.5O2 + M = 1 chlorite-smectite + A]. The presence of such interlayered chlorite-smectite which typically form at low T (150–200°C) suggests that the region was not affected by any major reheating events, which is consistent with the nature of the feldspars.

Keywords

chloriteigneous rocksalterationNa-amphibolesmectite interlayersparagenesis
Type
Mineralogy
Information
Mineralogical Magazine , Volume 59 , Issue 394 , March 1995 , pp. 129 - 141
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1995

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References

Abdel-Rahman, A.M. (1987) Crystallization of amphi-boles in the plutonic complexes of northeastern Egypt: implications for magma evolution. Neues Jahrb. Mineral, Abh., 157, 319–35.Google Scholar
Abdel-Rahman, A.M. (1990) Petrogenesis of early-orogenic diorites, tonalites and post-orogenic trondhjemites in the Nubian Shield. J. Petrol., 31, 1285–312.CrossRefGoogle Scholar
Abdel-Rahman, A.M. (1992) Mineral chemistry and paragenesis of astrophyllite from Egypt. Mineral. Mag., 56, 17–26.CrossRefGoogle Scholar
Abdel-Rahman, A.M. (1994) Nature of biotites from alkaline, calc-alkaline, and peraluminous magmas. J. Petrol., 35, 525–41.CrossRefGoogle Scholar
Abdel-Rahman, A.M. and Doig, R. (1987) The Rb-Sr geochronological evolution of the Ras Gharib segment of the northern Nubian Shield. J. Geol. Soc. London, 144, 577–86.CrossRefGoogle Scholar
Abdel-Rahman, A.M. and Martin, R.F. (1987) Late Pan-African magmatism and crustal development in northeastern Egypt. Geol. J., 22, 281–301.CrossRefGoogle Scholar
Abdel-Rahman, A.M. and Martin, R.F. (1990) The Mount Gharib A-type granite, Nubian shield: petrogenesis and role of metasomatism at the source. Contrib. Mineral. Petrol, 104, 173–83.CrossRefGoogle Scholar
Albee, A.L. (1962) Relations between the mineral association, chemical composition and physical properties of the chlorite series. Amer. Mineral., 47, 851–70.Google Scholar
AlDahan, A.A., Ounchanum, P. and Morad, S. (1988) Chemistry of micas and chlorite in Proterozoic acid metavolcanics and associated rocks from the Hastefalt area, Norberg Ore district, central Sweden. Contrib. Mineral. Petrol., 100, 19–34.CrossRefGoogle Scholar
Bailey, S.W. and Brown, B.E. (1962) Chlorite polytypism: I. Regular and semi random one-layer structures. Amer. Mineral, 47, 819–50.Google Scholar
Bailey, S.W. (1988) Chlorites: Structures and crystal chemistry. In Hydrous phyllosilicates (exclusive of micas), Bailey, S. W. (ed.), Mineralogical Society of America, Reviews in Mineralogy, 19, 347–403.CrossRefGoogle Scholar
Barker, F. (1979) Trondhjemite: definition, environment and hypothesis of origin. In Trondhjemites, Dacites and Related Rocks, Barker, F. (ed.), Amsterdam, Elsevier, 1-12.Google Scholar
Bettison, L.A. and Schiffman, P. (1988) Compositional and structural variations of phyllosilicates from the Point Sal ophiolite, California. Amer. Mineral, 73, 62–76.Google Scholar
Cathelineau, M. and Nieva, D. (1985) A chlorite solid solution geothermometer: the Los Azufres (Mexico) geothermal system. Contrib. Mineral. Petrol, 91, 235–44.CrossRefGoogle Scholar
Curtis, CD., 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, 471–81.CrossRefGoogle Scholar
Curtis, CD., 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, 375–86.CrossRefGoogle Scholar
Czamanske, G.K., Ishihara, S. and Atkin, S.A.(1981) Chemistry of rock-forming minerals of the Cretac-eous-Paleocene batholith in southwestern Japan and implications for magma genesis. J. Geophys. Res., 86, 10431–69.CrossRefGoogle Scholar
Deer, W.A., Howie, R.A. and Zussman, J. (1971) Rock-forming minerals, vol 3, Sheet Silicates, Longman, London, 270 pp.Google Scholar
Dodge, F.C.W. (1973) Chlorites from granitic rocks of the central Sierra Nevada batholith, California. Mineral. Mag., 39, 58–64.CrossRefGoogle Scholar
Eggleton, R.A. and Banfield, J.F. (1985) The alteration of granitic biotite to chlorite. Amer. Mineral, 70, 902–10.Google Scholar
Evarts, R. and Schiffman, P. (1983) Submarine hydrothermal metamorphism of the Del Puerto ophiolite, California. Amer. J. Scl, 283, 289–340.CrossRefGoogle Scholar
Ferry, J.M. (1979) Reaction mechanisms, physical conditions, and mass transfer during hydrothermal alteration of mica and feldspar in granitic rocks from south-central Maine. Amer. J. Sci., 278, 1025–56.CrossRefGoogle Scholar
Foster, M.D. (1962) Interpretation of the composition and a classification of the chlorites. U.S. Geological Survey Professional Paper, 414A, 1–33.Google Scholar
Hayes, J.B. (1970) Polytypism of chlorite in sedimentary rocks. Clays Clay Miner., 18, 285–306.CrossRefGoogle Scholar
Hey, M.H. (1954) A new review of the chlorites. Mineral. Mag., 30, 272–92.Google Scholar
Innoue, A. and Utada, M. (1983) Further investigations of a conversion series of dioctahedral mica/smectite in the Shinzan hydrothermal alteration area, northeast Japan. Clays Clay Miner., 31, 401-12.CrossRefGoogle Scholar
Innoue, A. and Utada, M. (1991) Smectite-to-chlorite transformation in thermally metamorphosed volca-noclastic rocks in the Kamikita area, northern Honshu, Japan. Amer. Mineral, 76, 628–40.Google Scholar
Keith, T.E.C, Mariner, R.H., Bargar, K.E., Evans, W.C. and Presser, T.S. (1984) Hydrothermal alteration in Oregon's Newberry volcano no. 2: Fluid chemistry and secondary-mineral distribution. Geothermal Resources Council Bulletin, 13, no. 4, 9–17.Google Scholar
Kranidiotis, P. and MacLean, W.H. (1987) Systematics of chlorite alteration at the Phelps Dodge massive sulfide deposit, Matagami, Quebec. Econ. Geol, 82, 1898–911.CrossRefGoogle Scholar
Kristmannsdottir, H. (1975) Clay minerals formed by hydrothermal alteration of basaltic rocks in Icelandic geothermal fields. Geologiska Foreningens i Stockholm Fbrhandlingar, 91, 289–92.CrossRefGoogle Scholar
Kristmannsdottir, H. (1979) Alteration of basaltic rocks by hydrothermal activity at 100-300°C. In International Clay Conference 1978, M.M. Mortland and V.C. Farmer (eds.), Elsevier, Amsterdam, Holland.Google Scholar
Laird, J. (1988) Chlorites: metamorphic petrology. In Hydrous phyllosilicates (exclusive of micas), Bailey, S.W. (ed.), Mineralogical Society of America, Reviews in Mineralogy, 19, 405–53.CrossRefGoogle Scholar
Lalonde, A. and Martin, R.F. (1983) The Baie-des-Moutons syenitic complex, La Tabatiere, Quebec. II. The ferromagnesian minerals. Can. Mineral, 21, 81–91.Google Scholar
Liou, J.G., Seki, Y., Guillemette, R.N. and Saki, H. (1985) Compositions and parageneses of secondary minerals in the Onikobe geothermal system, Japan. Chem. Geol, 49, 1–20.CrossRefGoogle Scholar
Morad, S. (1986) Mica-chlorite intergrowths in very low-grade metamorphosed sedimentary rocks from Norway. Neues Jahrb. Mineral, Abh., 154, 271–87.Google Scholar
Nutt, C.J. (1989) Chloritization and associated alteration at the Jabiluka unconformity-type uranium deposit, Northern Territory, Australia. Can. Mineral, 27, 41–58.Google Scholar
Refaat, A.M. and Abdallah, Z.M. (1979) Geochemical study of coexisting biotite and chlorite from Zaker granitic rocks of Zanjan area, northwest Iran. Neues Jahrb. Mineral, Abh., 136, 262–75.Google Scholar
Schiffman, P. and Smith, B. (1988) Petrology and O-isotope geochemistry of a fossil sea water hydro-thermal systems within the Solea graben, northern Troodos ophiolite, Cyprus. J. Geophys. Res., 93, 4612–24.CrossRefGoogle Scholar
Schneiderman, J.S. (1991) Petrology and mineral chemistry of the Ascutney Mountain igneous complex. Amer. Mineral., 76, 218–29.Google Scholar
Seki, Y., Liou, J.G., Guillmette, R., Sakai, H., Oki, Y., Hirano, T. and Onuki, H. (1983) Investigation of geothermal systems in Japan I. Onikobe geothermal area. Hydroscience and Geotechnology Laboratory, Saitama University, Memoir No. 3. Google Scholar
Shikazono, N. and Kawahata, H. (1987) Compositional differences in chlorite from hydrothermally altered rocks and hydrothermal ore deposits. Can. Mineral., 25, 465–74.Google Scholar
Shirozu, H. (1955) Iron-rich chlorite from Shogase, Kochi Preference, Japan. Mineral. J. (Japan), 1, 224–32.CrossRefGoogle Scholar
Shirozu, H. and Bailey, S.W. (1965) Chlorite polytyp-ism. Ill crystal structure of an orthohexagonal iron chlorite. Amer. Mineral., 50, 868–85.Google Scholar
Srodon, J. and Eberl, D.D. (1984) Illite. In Micas, Bailey, S.W., (ed.), Mineralogical Society of America, Reviews in Mineralogy, 13, 495–544.CrossRefGoogle Scholar
Steinfink, H. (1958) The crystal structure of chlorite. II. A triclinic polymorph. Acta. Crystallogr., 11, 195-8.CrossRefGoogle Scholar
Stoch, L. and Sikora, W.(1976) Transformations of micas in the process of Kaolinitization of granites and gneisses. Clays Clay Miner., 24, 156–62.CrossRefGoogle Scholar
Thornton, C.P. and Tuttle, O.F. (1960) Chemistry of igneous rocks. 1. Differentiation index. Amer. J. Sci., 258, 664–84.CrossRefGoogle Scholar
Veblen, D.R. and Ferry, J.M. (1983) A TEM study of the biotite-chlorite reaction and comparison with petrologic observations. Amer. Mineral., 68 1160-8.Google Scholar
Velde, B. (1977) A proposed phase diagram for illite, expanding chlorite and illite-montmorillonite mixed layered minerals. Clays Clay Miner., 25, 264–70.CrossRefGoogle Scholar
von Engelhardt, W. (1942) Die Strukturen von Thuringit, Bavalit und Chamosit und ihre Stelling in der Chloritgruppe. Zeits. Kristallogr., 104, 142-59.Google Scholar
Weaver, E.R. (1984) Shale-slate metamorphism in southern Appalachians. Development in Petrology, 10, Elsevier, Amsterdam, 239 pp.CrossRefGoogle Scholar