Hostname: page-component-78c5997874-ndw9j Total loading time: 0 Render date: 2024-11-10T12:19:34.774Z Has data issue: false hasContentIssue false
  • English
  • Français

Polytypism of Chlorite in Sedimentary Rocks

Published online by Cambridge University Press:  01 July 2024

John B. Hayes
John B. Hayes*
Affiliation:
Denver Research Center, Marathon Oil Company, Littleton, Colo. 80122
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.

Four chlorite polytypes of Bailey and Brown (1962) have been identified by X-ray diffraction in clay-size chlorites of soils, sediments, and sedimentary rocks: (1) IIb, the polytype of common metamorphic and igneous chlorites; (2) Ib(ß = 90°); (3) Ib(ß = 97°); (4) Ia. An additional stacking arrangement. Iba, is defined herein as disordered chlorite which lacks an h0l diffraction band in the 2.4–2.5 Å region.

Most type-I chlorites are authigenic, as demonstrated by thin-section petrography. Type-I chlorites form during diagenesis, or less commonly during halmyrolysis, at temperatures and pressures less than those of low-grade metamorphism. A type-1 crystallization sequence is proposed, from least to most stable: Iba → Ib(ß = 97°) → Ib(ß = 90°). Conditions of low-grade metamorphism usually are necessary to cause conversion of Iba(ß = 90°) to IIb, the most stable and common polytype. Chemical composition has little or no influence upon polytype relative stabilities; temperature is much more important.

Sediment source areas with high relief, abundant rainfall, cold climate, and which contain IIb-chlorite-bearing metamorphic rocks, may yield essentially unweathered IIb chlorite to sites of deposition. Thus, clay-size IIb chlorite in unmetamorphosed sedimentary rocks can be interpreted as detrital. Caution is required, however, because IIb may be able to form authigenically at submetamor-phic temperatures, because it is the most stable polytype. Petrographic evidence is useful in such cases.

Chlorite polytypism as a geothermometer can be applied to several geologic problems: (1) the authigenic versus detrital origin of clay minerals in sedimentary rocks, particularly in graywacke matrix; (2) the recognition of diagenetic facies or gradients, areally and stratigraphically, within given geologic provinces; (3) the detection of hydrothermal and incipient metamorphic effects. Chlorite polytypism merits general application as an interpretive tool.

Résumé

Résumé

Quatre polytypes de chlorites de Bailey et Brown (1962) ont été identifiés par diffraction aux rayons X dans des chlorites aux dimensions d’argile, de sols, dépôts et roches sédimentaires: (1) IIb, le polytype des chlorites métamorphiques et ignées communes, (2) Ib(ß = 90°); (3) Ib(ß = 97°); (4) la. Une disposition superposée supplémentaire. Ibd, est définie ici comme une chlorite en désordre manquant une bande de diffraction h0l dans la région de 2,4 à 2,5 Å.

La plupart des chlorites de type I sont authigéniques, comme il est démontré par la pétrographic des couches fines. Les chlorites du type I se forment au cours de la diagénèse, ou moins communément durant l’halmyrolyse, à des températures et des pressions plus faibles que celles du métamorphisme de basse catégorie. Une séquence de cristallisation du type I est proposée, depuis les moins stables aux plus stables: Ibd—Ib(ß = 97°) — Ib(ß = 90°). Des conditions de métamorphisme faible sont habituellement nécessaires pour entraîner la conversion de Ib(3 = 90°) en IIb, le polytype le plus stable et le plus commun. La composition chimique n’a que peu ou aucune influence sur les stabilités relatives des polytypes; la température est beaucoup plus importante.

Les zones de sources de dépôts à haut relief, avec chutes de pluie abondantes, climats froids, et qui contiennent des roches métamorphiques portant du chlorite de IIb peuvent essentiellement donner une chlorite IIb non inaltérée par les intempéries aux lieux de dépôts. Ainsi, la chlorite IIb de dimensions argile dans des roches sédimentaires non métamorphosées peut être interprétée comme détritique. Il faut toutefois faire attention parce que IIb peut se former d’une manière authigénique à des températures sous-métamorphiques. Parce que le polytype le plus stable. L’évidence pétrographique est utile dans de tels cas.

Le polytypisme de la chlorite est un géothermomètre qui peut être appliqué à plusieurs problèmes géologiques: (1) L’origine authigénique contre l’origine détritique des minéraux argileux dans les roches sédimentaires, en particulier dans les matrices “graywacke”; (2) la reconnaissance des faces ou pentes diagénétiques, par zone ou stratifiquement, à l’intérieur de provinces géologiques données; (3) la détection des effets métamorphiques hydrothermiques et naissants. Le polytypisme de la chlorite mérite une application générale en tant qu’outil d’interprétation.

Kurzreferat

Kurzreferat

Vier Chlorit-Typen von Bailey und Brown (1962) sind durch Röntgenbeugung in Chloriten von Tongrößen aus Böden, Sedimenten und Sedimentgesteinen identifiziert worden: (1) IIb der Polytyp aux gewöhnlichen metamorphischen und eruptiven Chloriten; (2) Ib(ß = 90°); (3) Ib (ß = 97°); (4) Ia. Eine zusätzliche Schichtungsanordnung, Ibd, wird hierin als ungeordneter Chlorit, dem ein h0l Beugungsband im 2,4–2,5 Å Bereich fehlt, bezeichnet.

Die meisten Typ-I Chlorite sind authigen, was durch Dünnschliff-Petrographie bewiesen wird. Die Typ-I Chlorite bilden sich während der Diagenese, oder weniger allgemein während der Halmyrolyse, bei Temperaturen und Drücken unterhalb derjenigen von geringem Metamorphismus. Es wird eine Kristallisationsfolge für Typ-I vorgeschlagen, die vom niedrigst- bis zum höchststabilen geht: IIb-Ib(gB = 97°) Ib(ß = 90°). Bedingungen von geringem Metamorphismus sind zumeist erforderlich um eine Umwandlung von Ib(ß = 90°) in IIb, den stabilsten und allgemeinsten Polytyp, herbeizuführen. Die chemische Zusammensetzung hat wenig oder keine Wirkung auf die relativen Stabilitäten der Polytype. Die Temperature ist viel maßgebender.

Herkunftsgebiete von Sedimenten mit Hochrelief, reichlichem Regenfall, kaltem Klima, die IIb-Chlorit führende, metamorphische Gesteine enthalten, dürften hauptsächlich unverwitterten IIb Chlorit an Ablagerungsstellen liefern. IIb-Chlorit von Tongröße in nicht-metamorphisiertem Sedimentgestein kann daher als detritisch angesehen werden. Es ist jedoch Vorsicht geboten, weil IIb sich bei submetamorphischen Temperaturen authigen zu bilden vermag, da es den stabilsten Polytyp darstellt. Petrographisches Beweismaterial ist in solchen Fällen nützlich.

Der Chlorit Polytypismus kann in verschiedenen geologischen Problemen als Geothermometer angewendet werden: (1) authigener gegen detritischer Ursprung von Tonmineralen in Sedimentgesteinen, besonders in Grauwacke Grundgestein; (2) Erkennen diagenetischer Fazies oder Gradienten, flachenmäßig oder stratigraphisch, innerhalb bestimmter geologischer Provinzen; (3) Auffindung hydrothermischer und beginnender metamorphischer Effekte. Der Chlorit Polytypism als Hilfsmittel für die Auslegung derartiger Probleme verdient weitverbreitete Anwendung.

Резюме

Резюме

Четыре политипных модификации хлоритов, выведенных теоретически Бейли и Брауном (1962), были рентгенографически установлены в глинистой фракции почв, в осадках и осадочных породах: (I) IIb—политип, распространенный среди обычных метаморфических и изверженных хлоритов; (2) Ib ((3 = 90°); (3) Ib ((3=97°); (4) Iа. В ряде образцов была установлена также дополнительная последовательность слоев Ib, приписываемая в настоящей работе неупорядоченному хлориту, не дающему дифракционных полос h0l в области 2,4-2,5 А.

Как показало изучение шлифов, большинство хлоритов тина I являются аутигенными. Хлориты типа I образуются в процессе диагенеза или же, что менее характерно, в результате гальмиролиза при температурах и давлениях меньших, чем характерные для метаморфизма низкой ступени. Предложена следующая последовательность кристаллизации хлоритов типа I—от наименее устойчивой к наиболее устойчивой модификации: Ibd→Ib (gB=970)→Ib (gB = 90°). Условия метаморфизма низкой ступени обычно являются необходимыми и достаточными для превращения модификации Ib (gB = 90°) в модификацию IIb, которая является наиболее устойчивым и распространенным политипом. Химический состав влияет весьма незначительно или же совсем не оказывает влияния на относительную устойчивость политипов; температура является гораздо более важным фактором.

Области материнских осадочных пород с высоким рельефом, обильными осадками и холодным климатом, в пределах которых развиты содержащие хлорит IIb метаморфические породы, могут служить источником слабо выветрелого хлорита IIb, поступающего в места осадкообразования. Таким образом, хлорит глинистой фракции в неметаморфизованных осадочных породах может рассматриваться как обломочный. Подобную интерпретацию следует однако проводить осторожно, так как модификация IIb может образовываться и аутигенно при субметаморфических температурах (она является наиболее устойчивым политипом). В подобных случаях весьма полезны петрографические доказательства.

Политипия хлоритов в качестве геотермометра может быть применена к решению ряда геологических проблем: (I) к решению вопроса об аутигенном или обломочном происхождении глинистых минералов в осадочных породах, в особенности в основной массе граувакк; (2) к определению диагенетических фаций или градиентов, регионального или стратиграфического, внутри данной геологической провинции; (3) к выяснению характера гидротермальных и начальных метаморфических эффектов. Таким образом, политипия хлоритов заслуживает широкого использования для решения генетических вопросов.

Type
Research Article
Information
Clays and Clay Minerals , Volume 18 , Issue 5 , December 1970 , pp. 285 - 306
Copyright
Copyright © 1970 The Clay Minerals Society

References

Bailey, S. W. and Brown, B. E. (1962) Chlorite poly-typism: I. Regular and semi-random one-layer structures: Am. Mineralogist 47. 819–850.Google Scholar
Ball, D. F. (1966) Chlorite clay minerals in Ordovician pumice-tuff and derived soils in Snowdonia, North Wales: Clay Minerals 6, 195–209.CrossRefGoogle Scholar
Bateman, M. K. (1967) Petrology and clay mineralogy of the Tertiary Poul Creek and Yakataga formations, Cape Yakataga, Alaska: Unpublished M. S. thesis, Univ. of Iowa, 131 pp.Google Scholar
Berry, R. W. and Johns, W. D. (1966) Mineralogy of the clay-sized fractions of some North Atlantic-Arctic Ocean bottom sediments: Geol. Soc. Am. Bull. 77, 183–196.CrossRefGoogle Scholar
Bonatti, E. and Arrhenius, G. (1965) Eolian sedimentation in the Pacific off northern Mexico: Marine Geol. 3, 337–348.CrossRefGoogle Scholar
Borst, R. L. (1966) A mineralogical study of some Lower Devonian (Helderberg) rocks of the central Hudson Valley, New York: J. Sediment. Petrol. 36, 775–793.Google Scholar
Brindley, G. W. (1961) Chlorite minerals: in The X-ray identification and crystal structures of clay minerals (Edited by Brown, G.): 242-296, Mineralogical Society, London.Google Scholar
Brown, B. E. and Bailey, S. W. (1963) Chlorite poly-typism: II. Crystal structure of a one-layer Cr-chlorite: Am. Mineralogist 48, 42–61.Google Scholar
Burst, J. F. (1958) “Glauconite” pellets: their mineral nature and applications to stratigraphie interpretations: Am. Assoc. Petroleum Geologists Bull. 42, 3 10–327.Google Scholar
Burst, J. F. (1969) Diagenesis of Gulf Coast clayey sediments and its possible relation to petroleum migration: Am. Assoc. Petroleum Geologists Bull. 53, 73–93.Google Scholar
Carrigy, M. A. and Mellon, G. B. (1964) Authigenic clay mineral cements in Cretaceous and Tertiary sandstones of Alberta: J. Sediment. Petrol. 34, 461–472.Google Scholar
Cummins, W. A. (1962) The greywacke problem: Liverpool and Manchester Geol. J. 3, 51–72.CrossRefGoogle Scholar
Dahl, H. M. (1965) Clay mineralogy of some Permian bentonites from the Delaware Basin area, Texas: Am. Mineralogist 50, 1637–1646.Google Scholar
Dott, R. H. Jr. (1964) Wacke, graywacke and matrix — what approach to immature sandstone classification?: J. Sediment. Petrol. 34, 625–632.Google Scholar
Dott, R. H. Jr. (1965) Mesozoic-Cenozoic tectonic history of the southwestern Oregon coast in relation to Cordilleran orogenesis: J. Geophys. Res. 70, 46874707.CrossRefGoogle Scholar
Droste, J. V., Bhattacharya, N. and Sunderman, J. A. (1962) Clay mineral alteration in some Indiana soils: Clays and Clay Minerals 9, 329–342.CrossRefGoogle Scholar
Dunoyer de Segonzac, G. (1968) The birth and development of the concept of diagenesis: Earth-Sci. Rev. 4, 153–201.CrossRefGoogle Scholar
Eggleton, R. A. and Bailey, S. W. (1967) Structural aspects of dioctahedral chlorite: Am. Mineralogist 52, 673–689.Google Scholar
Fairbridge, R. W. (1967) Phases of diagenesis and authigenesis: in Diagenesis in Sediments (Edited by Larsen, G. and Chilingar, G. V.): Developments in Sedimentology 8, 19–89, Elsevier, Amsterdam .Google Scholar
Foster, M. D. (1962) Interpretation of the composition and a classification of the chlorites: U.S. Geol. Surv. Prof. Paper 414-A, A1-33.Google Scholar
Gibbs, R. J. (1967) The geochemistry of the Amazon River system: Part I. The factors that control the salinity and the composition and concentration of the suspended solids: Geol. Soc. Am. Bull. 78, 1203–1232.CrossRefGoogle Scholar
Griffin, J. J., Windom, H. and Goldberg, E. D. (1968) The distribution of clay minerals in the World Ocean: Deep-Sea Res. 15, 433–459.Google Scholar
Harvey, R. D. and Vitaliano, C. J. (1964) Wall-rock alteration in the Goldfield district, Nevada: J. Geol. 72, 564–579.CrossRefGoogle Scholar
Hawkins, J. W. Jr. and Whetten, J. T. (1969) Graywacke matrix minerals: hydrothermal reactions with Columbia River sediments: Science 166, 868–870.CrossRefGoogle ScholarPubMed
Hayes, J. B. (1964) Polytypism of chlorite in sedimentary rocks (abs.): Program and Abstracts, 1964 Meeting of Clay Minerals Society, Madison, Wise., 11–12.Google Scholar
Heald, M. T. (1950) Authigenesis in West Virginia sandstones: J. Geol. 58, 624–633.CrossRefGoogle Scholar
Henbest, L. G. (1968) Diagenesis in oolitic limestones of Morrow (early Pennsylvanian) age in northwestern Arkansas and adjacent Oklahoma: U.S. Geol. Surv. Prof. Paper 594-H, H1-22.Google Scholar
Hollister, C. D. and Heezen, B. C. (1964) Modern graywacke-type sands: Science 146, 1573–1574.CrossRefGoogle ScholarPubMed
Hurley, P. M., Fairbairn, H. W., Pinson, W. H. Jr. and Hower, J. (1962) Unmetamorphosed minerals in the. Gunflint Formation used to test the age of the Animikie: J. Geol. 70, 484–492.CrossRefGoogle Scholar
Jackson, M. L. (1956) Soil Chemical Analysis-Advanced Course: published by the author, Madison, Wise., 991 pp.Google Scholar
Johnson, L. J. (1964) Occurrence of regularly interstratified chlorite-vermiculite as a weathering product of chlorite in a soil: Am. Mineralogist 49, 556–572.Google Scholar
Kisch, H. J. (1966) Chlorite-illite tonstein in high-rank coals from Queensland, Australia: notes on regional epigenetic grade and coal rank: Am. J. Sci. 264, 386397.CrossRefGoogle Scholar
Kisch, H. J. (1968) Coal rank and lowest-grade regional metamorphism in the southern Bowen Basin, Queensland, Australia: Geologie en Mijnbouw 47, 28–36.Google Scholar
Kuenen, Ph. H. (1966) Matrix of turbidites: experimental approach: Sedimentology 7, 267–297.CrossRefGoogle Scholar
Lane, H. R. (1967) Uppermost Mississippian and Lower Pennsylvanian conodonts from the type Morrowan region, Arkansas: J. Paleo. 41, 920–942.Google Scholar
Lister, J. S. and Bailey, S. W. (1967) Chlorite polytypism: IV. Regular two-layer structures: Am. Mineralogist 52, 1614–1631.Google Scholar
McCaleb, J. A. (1968) Lower Pennsylvanian ammonoids from the Bloyd Formation of Arkansas and Oklahoma: Geol. Soc. Am. Special Paper 96, 123 pp.Google Scholar
Muffler, L. J. P. and White, D. E. (1969) Active metamorphism of upper Cenozoic sediments in the Saltón Sea geothermal field and the Salton Trough, southeastern California: Geol. Soc. Am. Bull. 80, 157–182.CrossRefGoogle Scholar
Müller, G. (1967) Diagenesis in argillaceous sediments: in Diagenesis in Sediments (Edited by Larsen, G. and Chilingar, G. V.): Developments in Sedimentology 8, 127–177, Elsevier, Amsterdam .Google Scholar
Powers, M. C. (1967) Fluid-release mechanisms in compacting marine mudrocks and their importance in oil exploration: Am. Assoc. Petroleum Geologists Bull. 51, 1240–1254.Google Scholar
Schoen, R. (1964) Clay minerals of the Silurian Clinton ironstones, New York State: J. Sediment. Petrol. 34, 855–863.Google Scholar
Shirozu, H. (1958) X-ray powder patterns and cell dimensions of some chlorites in Japan, with a note on their interference colors: Mineralogical J. (Japan) 2, 209–223.CrossRefGoogle Scholar
Shirozu, H. (1963) Structural changes of some chlorites by grinding: Mineralogical J. (Japan) 4, 1-1 1.Google Scholar
Shirozu, H. and Bailey, S. W. (1965) Chlorite polytypism: III. Crystal structure of an orthohexagonal iron chlorite: Am. Mineralogist 50, 868–885.Google Scholar
Shirozu, H. and Bailey, S. W. (1966) Crystal structure of a two-layer Mg-vermiculite: Am. Mineralogist 51, 1124–1143.Google Scholar
Slaughter, M. and Milne, I. H. (1960) The formation of chlorite-like structures from montmorillonite: Clays and Clay Minerals 7, 114–124.Google Scholar
Steiner, A. (1968) Clay minerals in hydrothermally altered rocks at Wairakei, New Zealand: Clays and Clay Minerals 16, 193–213.CrossRefGoogle Scholar
Swindale, L. D. and Fan, Pow-Foong (1967) Transformation of gibbsite to chlorite in ocean bottom sediments: Science 157, 799–800.CrossRefGoogle ScholarPubMed
Turner, F. J. (1968) Metamorphic petrology: McGraw- Hill, New York , 403 pp.Google Scholar
Weaver, C. E. (1958) Geologic interpretation of argillaceous sediments: Am. Assoc. Petroleum Geologists Bull. 42, 254–309.Google Scholar
Weaver, C. E. (1959) The clay petrology of sediments: Clays and Clay Minerals 6, 154–187.Google Scholar
Yoder, H. S. and Eugster, H. P. (1955) Synthetic and natural muscovites: Geochim. Cosmochim. Acta 8, 225–280.CrossRefGoogle Scholar