Hostname: page-component-7479d7b7d-c9gpj Total loading time: 0 Render date: 2024-07-10T19:23:54.310Z Has data issue: false hasContentIssue false
  • English
  • Français

Regularly Interstratified Chlorite/Vermiculite in Contact Metamorphosed Red Beds, Newark Group, 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
Get access Rights & Permissions [Opens in a new window]

Abstract

A regularly interstratified chlorite/vermiculite occurs in red beds of the East Berlin Formation (Early Jurassic age) in the Connecticut Valley. The mineral is restricted to a 2.5-m wide zone of contact metamorphosed strata adjacent to and underlying the Hampden Basalt. Chemical and X-ray powder diffraction data indicate that the chlorite/vermiculite formed in response to lava-induced elevated temperatures and the availability of magnesium in the muds during and shortly after emplacement of the lava flow. Near the contact, hydrothermal fluids originating from the lava and from the synchronal weathering of basalt fragments by superheated pore waters provided a source of Mg. Further from the contact, magnesium was primarily derived from the thermal dissociation of dolomite. K2O concentrations and the distribution of clay minerals in the red mudstone suggest that the interstratified chlorite/vermiculite formed from preexisting illite or vermiculite as potassium was released and brucitic sheets were incorporated into interlayer positions.

Резюме

Резюме

Обычно переслаивающийся хлорит-вермикулит встречается в красных слоях формации Восточный Берлин (ранняя Юра) в Коннектикутской Долине. Этот минерал находится только в зоне контактного метаморфизма шириной 2,5 мили в отложениях, прилегающих к Базальту Хампден и подстилающих его. Химические анализы и данные порошкового метода рентгено-структурного анализа показывают, что хлорит-вермикулит образовался в результате повышенных температур, вызванных лавой, и присутствия магния в грязях во время и сразу после соприкосновения с потоком лавы. Около контакта гидротермальные жидкости, образующиеся в лаве и в результате одновременного выветривания базальтовых обломков перегретыми поровымн водами, служили источником магния. Дальше от контакта магний высвобождался в основном в результате термальной диссосиации доломита. Концентрации K2O и распределение глинистых минералов в красном аргиллите позволяют заключить, что переслаивающийся хлорит-вермикулит образовался из существующего уже иллита или вермикулита при высвобождении калия и включении бруситовых листов в межслойное пространство. [N. R.]

Resümee

Resümee

Eine regelmäßige Chlorit-Vermiculit Wechsellagerung kommt in den Rotschichten der East Berlin Formation (frühjurassisches Alter) im Connecticut Valley vor. Das Mineral ist auf eine 2,5 m breite kontaktmetamorphe Schicht beschränkt, die unmittelbar unter dem Hampden Basalt liegt. Chemische und Röntgendiffraktometer-Daten deuten darauf hin, daß die Chlorit-Vermiculit Wechsellagerung gebildet wurde, weil bedingt durch die Lava die Temperaturen erhöht waren, und im Schlick Magnesium während und kurz nach der Platznahme des Lavastroms zur Verfügung stand. Nahe dem Kontakt wurde Magnesium von hydrothermalen Lösungen geliefert, die von der Lava selbst stammen und die bei der gleichzeitig stattfindenden Veränderung von Basaltbruchstücken durch überhitzte Porenwässer entstehen. Weiter vom Kontakt entfernt stammt das Magnesium vor allem von der thermischen Dissoziation von Dolomit. Die K2O-Konzentrationen und die Tonmineralverteilung in den Rotschichten deuten darauf hin, daß die Chlorit-Vermiculit Wechsellagerung aus Illit oder Vermiculit gebildet wurden, indem Kalium herausgelöst wurde, und Brucitschichten in die Zwischenschichtpositionen eingebaut wurden. [U. W.]

Résumé

Résumé

Une chlorite-vermiculite régulièrement interstratifiée est trouvée dans les lits rouges de la East Berlin Formation (d’âge bas-Jurassique) dans la vallée du Connecticut. Le minéral est restreint à une zone de 2,5 m de largeur de couches métamorphosées au contact adjacentes à et sous le Hampden Basalt. Les données chimiques et de diffraction aux rayons-X indiquent que la chlorite-vermiculite a été formée en réponse à des températures élevées dues à la lave et à la présence de magnésium dans les boves pendant et peu après l'emplacement du flot de lave. Près du lieu de contact, les fluides hydrothermaux originant de la lave et de l'altération synchronique de fragments de basait par des eaux aux pores fortement échauffées ont fourni une souree de magnésium. Aux endroits plus éloignes du lieu de contact, le magnesium a été principalement dérivé de la dissociation thermale de dolomite. Les concentrations de K2O et la distribution de minéraux argileux dans les rouches argileuses rouges suggèrent que la chlorite-vermiculite a été formèe â partir d'illite ou de vermiculite pré-existante alors que le potassium était relâché et des couches brucitiques étaient incorporées dans des positions interfeuillet. [D. J.]

Keywords

ChloriteContact metamorphismHydrothermalMixed-layerRed bedsVermiculite
Type
Research Article
Information
Clays and Clay Minerals , Volume 28 , Issue 1 , February 1980 , pp. 1 - 11
Copyright
Copyright © Clay Minerals Society 1980

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

April, R. H., (1978) Clay mineralogy and geochemistry of the Triassic-Jurassic sedimentary rocks of the Connecticut Valley Amherst Univ. Massachusetts.Google Scholar
Almon, W. R. Fullerton, L. B. and Davies, D. K., (1976) Pore space reduction in Cretaceous sandstones through chemical precipitation of clay minerals J. Sediment. Petrology 46 89–96.Google Scholar
Bassett, W. A., (1959) The geology of vermiculite occurrences Clays & Clay Minerals 10 61–69.Google Scholar
Bence, A. E. and Albee, A. L., (1968) Empirical correction factors for the electron microanalysis of silicates and oxides J. Geol. 76 382–403.CrossRefGoogle 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. F. and Weaver, C. E., (1956) A regularly interstratified chlorite-vermiculite clay mineral Amer. Mineral. 41 497–504.Google Scholar
Brindley, G. W. and Wan, H. M., (1974) Use of long-spacing alcohols and alkanes for calibration of long spacings from layer silicates, particularly clay minerals. Clays & Clay Minerals TL 313–317.CrossRefGoogle Scholar
Carstea, D. D. Harward, M. E. and Knox, E. G., (1970) Formation and stability of hydroxy-Mg interlayers in phyllosilicates Clays & Clay Minerals 18 213–222.CrossRefGoogle Scholar
Chapman, R. W., (1965) Stratigraphy and petrology of the Hampden basalt in Central Connecticut .Google Scholar
Dunoyer de Segonzac, G., (1970) The transformation of clay minerals during diagenesis and low-grade metamorphism—a review Sedimentology 15 281–346.CrossRefGoogle Scholar
Early, J. W. Brindley, G. W. McVeagh, W. J. and Vanden Heuvel, R. C., (1956) A regularly interstratified montmorillonite-chlorite Amer. Mineral. 41 258–267.Google Scholar
Eberl, D. D., (1978) Reaction series for dioctahedral smectites Clays & Clay Minerals 26 327–340.CrossRefGoogle Scholar
Fabbi, B. P., (1972) A refined fusion X-ray fluorescence technique and determination of major and minor elements in silicate standards Amer. Mineral. 57 237–245.Google Scholar
Faust, G. T., (1949) Dedolomitization, and its relation to a possible derivation of a magnesium-rich hydrothermal solution Amer. Mineral. 34 789–823.Google Scholar
Harvey, R. D. and Beck, C. W., (1962) Hydrothermal regularly interstratified chlorite-vermiculite and tobermorite in alteration zones at Goldfield, Nevada Clays & Clay Minerals 9 343–354.CrossRefGoogle 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, I. G. Reed, A. A. and Carey, P. J., (1976) Paleo-geography of the East Berlin Formation, Newark Group, Connecticut Valley Amer. J. Sci. 276 1183–1207.CrossRefGoogle Scholar
Iiyama, J. T. and Roy, R., (1963) Controlled synthesis of het-eropolytypic (mixed-layer) clay minerals Clays & Clay Minerals 10 4–22.Google Scholar
Jackson, M. L., (1963) Interlayering of expansible layer silicates in soils by chemical weathering Clays & Clay Minerals 11 29–46.Google Scholar
Jackson, M. L., (1976) Soil Chemical Analysis—Advanced Course 2nd.Google Scholar
Jaeger, J. C., (1957) The temperature in the neighborhood of a cooling intrusive sheet Amer. J. Sci. 255 306–318.CrossRefGoogle Scholar
Johnson, L. J., (1964) Occurrence of regularly interstratified chlorite-vermiculite as a weathering product of chlorite in a soil Amer. Mineral. 49 556–572.Google Scholar
Kinter, E. B. and Diamond, S., (1956) A new method for preparation and treatment of oriented-aggregate specimens of soil clays for X-ray diffraction analysis Soil. Sci. 81 111–120.CrossRefGoogle Scholar
Kittrick, J. A., (1960) Cholesterol as a standard in the X-ray diffraction of clay minerals Soil. Sci. Soc. Amer. Proc. 24 17–20.CrossRefGoogle Scholar
Kossovskaya, A. G., (1972) Genetic types and paragenetic associations of minerals of the corrensite group International Clay Conf., preprints v.1 341–342.Google Scholar
Lippmann, F., (1954) Über einen Keuperton von Zaiserwei-her bei Maulbronn Heidelb. Beitr. Mineral. Petrogr. 4 130–134.Google Scholar
Lippmann, F., (1956) Clay minerals from the Röt Member of the Triassic near Göttingen, Germany J. Sediment. Petrology 26 125–139.CrossRefGoogle Scholar
Peterson, M. N. A., (1961) Expandable chloritic clay minerals from Upper Mississippian carbonate rocks of the Cumberland Plateau in Tennessee Amer. Mineral. 46 1245–1269.Google Scholar
Post, J. L. and Janke, N. C., (1974) Properties of “swelling” chlorite in some Mesozoic formations of California Clays & Clay Minerals 22 67–77.CrossRefGoogle Scholar
Reed, A. A., (1976) Stratigraphy, depositional environments and sedimentary petrology of the Lower Jurassic East Berlin Formation, central Connecticut .Google Scholar
Ross, G. J., (1975) Experimental alteration of chlorites into vermiculites by chemical oxidation Nature 255 133–134.CrossRefGoogle Scholar
Ross, G. J. and Kodama, H., (1976) Experimental alteration of a chlorite into a regularly interstratified chlorite-vermiculite by chemical oxidation Clays & Clay Minerals 24 183–190.CrossRefGoogle Scholar
Sarkisyan, S. G. and Kotelnikov, D. D., (1972) Genesis and thermodynamic stability of dioctahedral and trioctahedral mixed-layer minerals in sedimentary rocks International Clay Conf., preprints v.1 343–352.Google Scholar
Sawhney, B. L., Dixon, J. B. and Weed, S. B., (1977) Interstratification in layer silicates Minerals in Soil Environments Madison, Wisconsin Soil Sci. Soc. Amer..Google Scholar
Shapiro, L. (1975) Rapid analysis of silicate, carbonate, and phosphate rocks—revised edition: U.S. Geol. Surv. Bull. 1401, 76 pp.Google Scholar
Shimoda, S., (1969) New data for tosudite Clays & Clay Minerals 17 179–183.CrossRefGoogle Scholar
Shover, E. F., (1964) Clay-mineral-environment relationships in Cisco (Upper Pennsylvania) clays and shales, North-Central Texas Clays and Clay Minerals, Proc. 12th National Conf. 1963 431–443.Google Scholar
Sudo, T. Takahashi, H. and Matsui, H., (1954) Longspacing of 30 Å from a fireclay Nature 173 161.Google Scholar
Velde, B., (1972) Phase equilibria for dioctahedral expandable phases in sediments and sedimentary rocks Int. Clay Conf. Proc 235–248.Google Scholar
Velde, B., (1977) A proposed phase diagram for illite, expanding chlorite, corrensite and illite-montmorillonite mixed-layered minerals Clays & Clay Minerals 25 264–270.CrossRefGoogle Scholar
Velde, B., (1977) Clays and Clay Minerals in Natural and Synthetic Systems Amsterdam Elsevier Scientific Publ. Co..Google Scholar
Walker, G. F. and Brown, G., (1961) Vermiculite minerals The X-ray Identification and Crystal Structures of Clay Minerals London Mineralogical Society 297–324.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 Developments in Sedimentology, v. 22: Elsevier Scientific Publ. Co..CrossRefGoogle Scholar
Weaver, C. E. and Pollard, L. D., (1975) The Chemistry of Clay Minerals Amsterdam Developments in Sedimentology, v. 15: Elsevier Scientific Publ. Co..Google Scholar
Winkler, H. G. F., (1965) Petrogenesis of Metamorphic Rocks New York Springer-Verlag.CrossRefGoogle Scholar
Winkler, H. G. F., (1976) Petrogenesis of Metamorphic Rocks 4th New York Springer-Verlag.Google Scholar
Wyart, J. and Sabatier, G., (1966) Synthèse hydrothermale de la corrensite Bull. Groupe Fr. Argiles 18 33–40.CrossRefGoogle Scholar