Hostname: page-component-cd9895bd7-8ctnn Total loading time: 0 Render date: 2024-12-26T09:26:13.007Z Has data issue: false hasContentIssue false

Origin of the Permo-Triassic clay mica assemblage

Published online by Cambridge University Press:  09 July 2018

C. V. Jeans
Affiliation:
Department of Earth Sciences, Downing Street, Cambridge CB2 3EQ, UK
J. G. Mitchell
Affiliation:
School of Physics, The University, Newcastle upon Tyne NE1 7RU, UK
M. Scherer
Affiliation:
Shell España N.V., Madrid, Spain
M. J. Fisher
Affiliation:
Nevis Associates Ltd., Helensburgh, Dumbartonshire G84 8DD, UK

Abstract

Clay mica is the predominant component of the fine-grained siliciclastic sediments of the Western European Permo-Trias and it may occur as the sole component of the clay assemblage. Its characteristics have been studied by chemical analysis, radioisotope (K/Ar) data, X-ray diffraction and electron microscopy in the clay assemblages from Triassic and Permian sediments in Spain, Western Approaches, South Devon and East Yorkshire. The clay mica is a ferric dioctahedral mineral containing on average 6.5% Fe2O3 and 7.5% K2O. Crystal thickness ranges from 8 × 10 Å to 115 × 10 Å, and varies with geological, stratigraphical and grain-size factors. Radioisotope data and geological considerations suggest that much of the Permo-Triassic clay mica was formed originally in coeval desert soils rather than being derived from pre-existing rocks. It was then eroded, sometimes mixed with much older material, and deposited as fine-grained detritus in adjacent areas. Upon deep burial, this detrital mica assemblage underwent recrystallization with the development of euhedral crystals and the alteration of the K/Ar values.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1994

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

Bender Koch, C. (1991) Non-crystalline hydrous feldspathoids in Late Permian carbonate rock. Clay Miner. 26, 527534.CrossRefGoogle Scholar
Bennet, G., Copestake, P. & Hooker, N.P. (1985) Stratigraphy of the Britoil 72/10-1A Well, Western Approaches. Proc. Geol. Assoc. 96, 225262.Google Scholar
Deconinck, J.F., Strasser, A. & Debrabant, P. (1988) Formation of illitic minerals at surface temperatures in Purbeckian sediments (Lower Berriasian, Swiss and French Jura). Clay Miner. 23, 91103.Google Scholar
Eberl, D.D., Środoń, J. & Northrop, H.R. (1986) Potassium fixation in smectite by wetting and drying. Pp. 296- 326 in: Geochemical Processes at Mineral Surfaces (Davis, J.A. & Hayes, K.F., editors). Am. Chem. Soc. Sym. Series 323/14.Google Scholar
Eberl, D.D., Velde, B. & Mccormick, T. (1993) Synthesis of illite-smectite at Earth surface temperatures and high pH. Clay Miner. 28, 4960.Google Scholar
Fisher, M.J. & Jeans, C.V. (1982) Clay mineral stratigraphy in the Permo-Triassic red bed sequence of BNOC 72/10- 1A, Western Approaches, and the South Devon coast. Clay Miner. 17, 7989.Google Scholar
Gabis, V. (1963) Etude mineralogique et gGochimique de la sGrie sedimentaire oligocGne du Velay. Bull. Soc. franc. Mineral. Cristallogr. 86, 315354.Google Scholar
Griffn, G.M. (1971) Interpretation of X-ray diffraction data. Pp. 541-569 in: Procedures in Sedimentary Petrology (Carver, R.E., editor), Wiley Interscience.Google Scholar
Harland, W.B., Armstrong, R.L., Cox, A.V., Craig, L.E., Smith, A.G. & Smith, D.G. (1990) A Geological Time Scale 1989. Cambridge University Press.Google Scholar
Hemingway, J.E. & Riddler, G.P. (1982) Basin inversion in North Yorkshire. Trans. Inst. Mining Metall. B91, 175186.Google Scholar
Jeans, C.V. (1978) The origin of the Triassic clay assemblages of Europe with special reference to the Keuper Marl and Rhaetic of parts of England. Phil. Trans. Roy. Soc. Series A, 549-639.Google Scholar
Jeans, C.V. (1980) Early submarine lithification in the Red Chalk and Lower Chalk of Eastern England: a bacterial control model and its implications. Proc. Yorks. Geol. Soc. 43, 81157.Google Scholar
Jung, J. (1954) Les illites du bassin oligocbne de Salins (Cantal). Bull. Soc. franc. Mindral Cristallogr. 72, 12311249.Google Scholar
Keller, W.D. (1958) Glauconitic mica in the Morrison Formation in Colorado. Clays Clay Miner. 5, 120128.Google Scholar
Kent, P.E. (1980) Subsistence and uplift in East Yorkshire and Lincolnshire: a double inversion. Proc. York. Geol. Soc. 42, 505524.Google Scholar
Kirby, G.A., Smith, K., Smrrh, N.J.P. & Swallow, P.W. (1987) Oil and gas generation in eastern England. Pp. 171-180 in: Petroleum Geology of North West Europe (Brooks, J. & Glennie, K., editors). Graham & Trotman, London.Google Scholar
Klug, J.P. & Alexander, L.E. (1954) Crystallite-size determination from line broadening. Chapter 9 in: X-ray Diffraction Procedures. J. Wiley & Sons, New York.Google Scholar
Lippmann, F. & Berthold, C. (1992) Der Mineralbestand des Unteren Muschelkalkes yon Geislingen bei Schw∼ibisch Hall (Deutschland). NeuesJahrb. Miner. Abh. 164, 183209.Google Scholar
Lucas, J. (1962) La transformation des minéraux argileux dans la sédimentation: Études sur les argiles du Trias. Mém. Serv. Carte Géol. Als-Lorr. 23.Google Scholar
Mader, D. (1980) Petrographie und Genese der Brockelb∼ inke im Oberen Buntsandstein der Westeifel. Oberrhein, Geol. Abh. 29, 128.Google Scholar
Mader, D. (1984) Fluviatile Sedimentation im Wechsel mit Pedogenese in der Marginalfazies der Swischenschichten im Oberen Buntsandstein von Luxemburg. Oberrhein, Geol. Abh. 33, 1566.Google Scholar
Mader, D. (1992) Evolution of Palaeoecology and Palaeoenvironment of Permian and Triassic Fluvial Basins in Europe. Vol. 1, Western & Eastern Europe, pp. 1-738; Vol. 2, Southeastern Europe & Index, pp. 739-1340. Gustav Fischer Verlag, Stuttgart.Google Scholar
Mamy, J. & Gaultier, J.P. (1975) Etude de 1'évolution de I'ordre cristallin dans la montmorfllonite en relation avec la diminution de 1'échangeabilité du potassium. Proc. Int. Clay Conf. Mexico City, 149-155.Google Scholar
Mitchell, J.G. & Euwe, M.G. (1988) A model of singlestage concomitant potassium-argon exchange in acidic lavas from the Erlend Volcanic Complex, north of Shetland Islands. Chem. Geol. (Isotope Geoscience Section) 72, 95109.Google Scholar
Mitchell, J.G. & Ineson, P.R. (1988) Models of singlestage concomitant potassium-argon exchange: an interpretation of discordant whole-rock K-Ar data from hydrothermally altered rocks of the South Pennine Orefield, UK. Earth Planet Sci. Lett. 88, 6981.CrossRefGoogle Scholar
Norrish, K. & Pickering, J.G. (1983) Clay minerals. Pp. 281-308 in: Soils: an Australian Viewpoint, Division of Soils, CSIRO, Melbourne/Academic Press, London.Google Scholar
Parry, W.T. & Reeves, C.C. (1966) Lacustrine glauconitic mica from pluvial Lake Mound, Lynn and Terry Counties, Texas. Am. Miner. 51, 229235.Google Scholar
Porrenga, D.H. (1968) Non-marine glauconitic illite in the Lower Oligocene of Aarbenburg, Belgium. Clay Miner. 7, 421430.Google Scholar
Singer, A. (1988) lllite in aridic soils, desert dusts and desert loess. Sed. Geol. 59, 251259.Google Scholar
Singer, A. (1989) Illite in the hot-aridic soil environment. Soil Sci. 147, 126133.Google Scholar
Washington, H.S. (1930) The Chemical Analysis’ of Rocks, 4th edition. John Wiley & Sons, New York.Google Scholar
Wilkinson, P., Mitchell, J.G., Carttermole, P.J. & Downie, C. (1986) Volcanic chronology of the Meru-Kilimanjaro region, northern Tanzania. J. Geol. Soc. Lond. 143, 601605.Google Scholar
Woods, P.J.E. (1973) Potash exploration in Yorkshire: Boulby mine pilot borehole. Trans. Inst. Mining Metall. B82, 99106.Google Scholar
Wright, V.P., Marrioti, S.B. & Vanstone, S.D. (1991) A “reg” palaeosol from the Lower Trias of South Devon: stratigraphic and palaeoclimatic implications. Geol. Mag. 128, 517523.Google Scholar