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Trioctahedral Smectite and Interstratified Chlorite/Smectite in Jurassic Strata of the Connecticut Valley

Published online by Cambridge University Press:  01 July 2024

Richard H. April
Richard H. April*
Affiliation:
Department of Geology, Colgate University, Hamilton, New York 13346
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Abstract

Trioctahedral smectite and regularly interstratified chlorite/smectite in strata of the East Berlin Formation of the Connecticut Valley are largely restricted to black shale and gray mudstone deposited in alkaline, perennial lakes. The precursor of the mixed-layer clay appears to have been a smectite. Alkaline lake waters and inherited pore waters rich in magnesium favored the transformation of smectite to mixed-layer chlorite/smectite by fixation of brucitic interlayers into the smectite unit structure. Gray mudstones containing the mixed-layer chlorite/smectite are invariably underlain by magnesium-rich black shale—a possible source of Mg for the clay mineral transformations. The black shale is composed predominantly of Mg-rich trioctahedral smectite of probable authigenic origin.

Резюме

Резюме

Триоктаэдрический смектит и регулярно внутринапластованный хлорит/смектит в пласте формации Восточного Берлина в Долине Коннектикута ограничены, в основном, до черной сланцеватой глины и серой иловатой глины, осажденных в щелочных непересыхающих озерах. Смектит кажется предшественником смешанно-слойной глины. Воды щелочных озер и наследственные пористые воды, богатые в магний, способствовали преобразованию смектита в смещаннослойный хлорит/смектит путем фиксации бруцитовых промежуточных слоев в элементарную структуру смектита. Черные сланцеватые глины, богатые в магний—возможные источники магния, используемые для преобразования глинистых минералов—неизменно располагаются под серыми иловатыми глинами, содержающими смешанно-слойный хлорит/смектит. Черная сланцеватая глина, в основном, состоит из богатого в магний триоктеэдрического смектита, вероятно, аутигенного начала. [Е.С.]

Resümee

Resümee

Trioktaedrischer Smektit und regelmäßge Chlorit/Smektit-Wechsellagerungen sind in den Schichten der East Berlin Formation des Connecticut Valley hauptsächlich auf schwarzen Schieferton und grauen Tonstein beschränkt, die in alkalischen permanenten Seen abgelagert sind. Der Vorläufer der Wechsellagerung scheint ein Smektit gewesen zu sein. Alkalische Seewässer und Mg-reiche Porenwässer begänstigten die Umwandlung des Smektit in die Chlorit/Smektit-Wechsellagerung, indem brucitische Zwischenlagen in die Smektit-Struktur eingebaut wurden. Unter den grauen Tonsteinen, die die Chlorit/Smektit-Wechsellagerung enthalten, findet sich immer ein Mg-reicher schwarzer Schieferton, der eine mögliche Mg-Quelle für die Tonmineralumbildung ist. Der schwarze Schieferton besteht vor allem aus Mgreichem trioktaedrischem Smektit mit wahrscheinlich authigener Entstehung. [U.W.]

Résumé

Résumé

La smectite trioctaèdre et la chlorite/smectite régulièrement interstratifiée dans les lits de la formation East Berlin de la vallée du Connecticut sont pour la plupart restrientes au shale noir et à l'argilite grise déposés dans des lacs alkalins perpétuels. Le précurseur de l'argile à couches mélangres semble avoir été une smectite. Les eaux alkalines du lac et les eaux héritées des pores, riches en magnésium, ont favorisé la transformation de la smectite en chlorite/smectite à couches mélangées par la fixation d'intercouches brucitiques dans la structure unitaire de la smectite. On trouve invariablement des shales noirs riches en magnésium, une source possible de Mg pour les transformations de minéral argileux, sous des argilites grises contenant la chlorite/smectite à couches mélangées. Le shale noir est composé surtout de smectite trioctaèdre riche en Mg et probablement d'origine authigénique. [D.J.]

Keywords

Alkaline lakeChloriteInterstratificationMagnesiumMudstoneShaleSmectite
Type
Research Article
Information
Clays and Clay Minerals , Volume 29 , Issue 1 , February 1981 , pp. 31 - 39
Copyright
Copyright © 1981, The Clay Minerals Society

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References

Almon, W. R. Fullerton, L. B. and Davies, D. K., (1976) Pore space reduction in Cretaceous sandstones through chemical precipitation of clay minerals J. Sed. Pet. 46 89–96.Google Scholar
April, R. H. (1978) Clay mineralogy and geochemistry of the Triassic-Jurassic sedimentary rocks of the Connecticut Valley: Ph.D. dissertation, Univ. Massachusetts, Amherst, Massachusetts, 206 pp. (unpublished).Google Scholar
April, R. H., (1980) Regularly interstratified chlorite/vermiculite in contact metamorphosed red beds, Newark Group, Connecticut Valley Clays & Clay Minerals 28 1–11.Google Scholar
Blatter, C. L. Roberson, H. E. and Thompson, G. R., (1973) Regularly interstratified chlorite-dioctahedral smectite in dike-intruded shales, Montana Clays & Clay Minerals 21 207–212.CrossRefGoogle Scholar
Bradley, W. H. and Fahey, J. J., (1962) Occurrence of stevensite in the Green River Formation of Wyoming Amer. Mineral. 47 996–998.Google Scholar
Brindley, G. W. and Brown, G., (1961) Chlorite minerals The X-ray Identification and Crystal Structures of Clay Minerals London Mineralogical Society.Google Scholar
Caillère, S. and Hénin, S., (1951) The properties and identification of saponite (bowlingite) Clay Miner. 1 138–144.CrossRefGoogle Scholar
Carstea, D. D. Harward, M. E. and Know, E. G., (1970) Formation and stability of hydroxy-Mg interlayers in phyllosilicates Clays & Clay Minerals 18 213–222.CrossRefGoogle Scholar
Droste, J. B. (1961) Clay minerals in playa sediments of the Mojave Desert, California: Calif. Div. Mines Spec. Report 69, 19 pp.Google Scholar
Dunoyer de Segonzac, G., (1970) The transformation of clay minerals during diagenesis and low-grade metamorphism—a review Sedimentology 15 281–346.Google Scholar
Dyni, J. R. (1976) Trioctahedral smectite in the Green River Formation, Duchesne County, Utah: U.S. Geol. Surv. Prof. Pap. 967, 14 pp.Google Scholar
Faust, G. T. and Murata, K. J., (1953) Stevensite, redefined as a member of the montmorillonite group Amer. Mineral. 38 973–987.Google Scholar
Grim, R. E. Droste, J. B. Bradley, W. F. and Swineford, A., (1960) A mixed-layer clay mineral associated with an evaporite Clays and Clay Minerals, Proc. 8th Natl. Conf., Norman, Oklahoma, 1959 New York Pergamon Press 228–236.Google Scholar
Harward, M. E. Carstea, D. D. and Sayegh, A. H., (1969) Properties of vermiculites and smectites—expansion and collapse Clays & Clay Minerals 16 437–447.Google Scholar
Hay, R. L. (1966) Zeolites and zeolitic reactions in sedimentary rocks: Geol. Soc. Amer. Spec. Pap. 85, 130 pp.Google Scholar
Hower, J. and Mowatt, T. C., (1966) The mineralogy of illites and mixed-layer illite/montmorillonites Amer. Mineral. 51 825–854.Google Scholar
Hubert, J. F. Reed, A. A. and Carey, P. J., (1976) Paleogeography of the East Berlin Formation, Newark Group, Connecticut Valley Amer. J. Sci. 276 1183–1207.Google Scholar
Hubert, J. F., Reed, A. A., Dowdall, W. L., and Gilchrist, J. M. (1978) Guide to the Red Beds of Central Connecticut: 1978 Field Guide, Eastern Section Soc. of Econ. Paleon. Mineral., Contr. 32, Dept. Geology, Univ. Massachusetts, Amherst, Massachusetts, 129 pp.Google Scholar
Millot, G., (1970) Geology of Clays New York Springer-Verlag.Google Scholar
Müller, G. Irion, G. and Forstner, U., (1972) Formation and diagenesis of inorganic Ca-Mg carbonates in the lacustrine environment Naturwissenschaften 59 158–164.CrossRefGoogle Scholar
Papke, K. G., (1972) A seprolite-rich playa deposit in southern Nevada Clays & Clay Minerals 20 211–215.CrossRefGoogle Scholar
Papke, K. G. (1970) Montmorillonite, bentonite, and fuller’s earth deposits in Nevada: Nevada Bur. Mines Bull. 76, 47 pp.Google Scholar
Reynolds, R. C. and Hower, J., (1970) The nature of interlayering in mixed-layer illite-montmorillonites Clays & Clay Minerals 18 25–36.Google Scholar
Suchecki, R. K. Perry, E. A. and Hubert, J. F., (1977) Clay petrology of Cambro-Ordovician continental margin, Cow Head Klippe, western Newfoundland Clays & Clay Minerals 25 163–170.CrossRefGoogle Scholar
Tardy, Y. and Garrels, R. M., (1974) A method of estimating the Gibbs energies of formation of layer silicates Geochim. Cosmochim. Acta 38 1101–1116.CrossRefGoogle Scholar
Velde, B. and Hower, J., (1963) Petrological significance of illite polymorphism in Paleozoic sedimentary rocks Amer. Mineral. 48 1239–1254.Google Scholar
Velde, B., (1977) Clays and Clay Minerals in Natural and Synthetic Systems Amsterdam Elsevier.Google Scholar
Walker, G. R. and Brown, G., (1961) Vermiculite minerals The X-ray Identification and Crystal Structures of Clay Minerals London Mineralogical Society.Google Scholar
Weaver, C. E. and Pollard, L. D., (1975) The Chemistry of Clay Minerals Amsterdam Elsevier.Google Scholar
Weaver, C. E. and Beck, K. C., (1977) Miocene of the S. E. United States—A Model for Chemical Sedimentation in a Peri-Marine Environment Amsterdam Elsevier.Google Scholar
Weaver, R. M. Jackson, M. L. and Syers, J. K., (1976) Clay mineral stability as related to activities of aluminum, silicon, and magnesium in matrix solution of montmorillonite-containing soils Clays & Clay Minerals 24 246–252.Google Scholar