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Origin of montmorillonite in the early Jurassic shales of NW Scotland

Published online by Cambridge University Press:  01 May 2009

K. Amiri-Garroussi
K. Amiri-Garroussi
Affiliation:
Department of Geology and Mineralogy, University of Oxford, Parks Road, Oxford, OX1 3PR, England
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Summary

Clay mineral analysis of shales in the early Liassic Lower Broadford Beds of the Hebrides reveals the presence of abundant quantities of montmorillonite whereas the Upper Broadford Beds contain illite, kaolinite and subordinate mixed layer minerals together with chlorite. Montmorillonite enrichment of the Lower Broadford Beds as a consequence of recent weathering contamination by doleritic sills can effectively be ruled out. It is argued that the montmorillonite may have been derived from the weathering of basic igneous rocks exposed in the sediment source area during Late Triassic times. By Upper Broadford Beds times, the igneous source was either eroded away or transgressed by the early Liassic sea.

Type
Articles
Information
Geological Magazine , Volume 114 , Issue 4 , July 1977 , pp. 281 - 290
Copyright
Copyright © Cambridge University Press 1977

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References

Althaus, E. & Johannes, W. 1969. Experimental metamorphism of sodium chloride-bearing aqueous solutions by reaction with silicates. Am. J. Sci. 267, 87–98.CrossRefGoogle Scholar
Ambroggi, R. 1963. Étude geologique du versant meridional du Haute Atlas occidental et de la Plaine du Souss, Marocco. Ser. Geol. Notes Mem. 152, 1–321.Google Scholar
Audley-Charles, M. G. 1970. Triassic palaeogeography of the British Isles. Q. Jl geol. Soc. Lond. 126, 19–47.CrossRefGoogle Scholar
Austin, G. S. & Leininger, R. K. 1976. The effect of heat-treatment on sedimented mixed layer illitesmectites as related to quantitative clay mineral determination. J. sedim. Petrol. 46, 206–15.Google Scholar
Ballard, R. D. & Uchupi, E. 1975. Triassic rift structures in the Gulf of Main. Bull. Am. Ass. Petrol. Geol. 59, 1041–72.Google Scholar
Biscaye, P. E. 1965. Mineralogy and sedimentology of deep-sea clays in the Atlantic Ocean and adjacent seas and oceans. Bull. geol Soc. Am. 76, 803–31.CrossRefGoogle Scholar
Blatter, C. L., Robertson, H. E. & Thompson, G. R. 1973. Regularly interstratified chlorite-dioctahedral smectite in dyke intruded shales, Montana. Clays & Clay Miner. 21, 207–12.CrossRefGoogle Scholar
Bodine, M. W. & Fernald, T. H. 1973. EDTA dissolution of gypsum, anhydrite and Ca–Mg carbonates. J. sedim. Petrol. 43, 1152–6.Google Scholar
Bott, M. H. P. 1971. Evolution of young continental margins and formation of shelf basins. Tectonophysics 11, 319–27.CrossRefGoogle Scholar
Bradshaw, M. J. 1975. Origin of montmorillonite bands in the Middle Jurassic of eastern England. Earth Planet. Sci. Lett. 26, 245–52.CrossRefGoogle Scholar
Brindley, G. W. 1957. Fuller's Earth from Dry Branch Georgia, a montmorillonite-cristoballite clay. Clay Miner. Bull. 3, 167 only.Google Scholar
Brown, G., Catt, J. A. & Weir, A. H. 1969. Zeolites of the Clinoptilite-Heulandite type in sediments of south-east England. Mineral Mag. 37, 480–8.Google Scholar
Correia, M. & Maury, R. 1975. Effects thérmiques, mineralogiques et chimique de l'intrusion d'un dyke basaltique dans le Toarcian des Causses. Bull. Centre Rech. Pau SNPA 9, 245–59.Google Scholar
Cosgrove, M. E. 1975. Mineral suites in the post-Armorican formations of southwest England. Proc. Ussher Soc. 3, 243 only.Google Scholar
Faerseth, R. B., MacIntyre, R. M. & Naterstad, J. 1976. Mesozoic alkaline dykes in the Sunnhordland Region, Western Norway: ages, geochemistry and regional significance. Lithos 9, 331–45.Google Scholar
Hallam, A. 1959. Stratigraphy of the Broadford Beds of Skye, Raasay and Applecross. Proc. Yorks. geol. Soc. 32, 165–84.CrossRefGoogle Scholar
Hallam, A. 1960. A sedimentary and faunal study of the Blue Lias of Dorset and Glamorgan. Phil. Trans. R. Soc. B 243, 1–44.Google Scholar
Hallam, A. 1971. Mesozoic geology and the opening of the north Atlantic. J. Geol. 79, 129–54.Google Scholar
Hallam, A. & Sellwood, B. W. 1968. Origin of Fuller's Earth in the Mesozoic of southern England. Nature, Lond. 1193–5.Google Scholar
Hallam, A. & Sellwood, B. W. 1976. Middle Mesozoic sedimentation in relation to tectonics in the British area. J. Geol. 84, 301–33.Google Scholar
Henderson, G. 1973. The geological setting of Western Greenland Basin in the Baffin Bay region. Geol. Surv. Canada, Paper 71–23, 521–35.Google Scholar
Hourang, M. & Hatton, A. A. 1974. Deep weathering in the Great Whin Sill, northern England. Proc. York. geol. Soc. 40, 105–14.Google Scholar
Howitt, F., Aston, E. R. & Jacqué, M. 1975. Occurrence of Jurassic volcanics in the North Sea. In Petroleum and the Continental Shelf of North-West Europe (ed. Woodland, A.), pp. 379–86. Applied Science Publishers.Google Scholar
Jansa, L. F. & Wade, J. A. 1975. The geology of the continental margin off Nova Scotia and Newfoundland. Geol. Surv. Canada, Paper 74–30, 2, vol. 2, 51–103.Google Scholar
Lee, G. W. 1920. The mesozoic rocks of Applecross, Raasay and north-east Skye. Mem. geol. Surv. U.K. 93 pp.Google Scholar
Lee, G. W. & Bailey, E. B. 1925. The pre-Tertiary geology of Mull, Loch Mine and Oban. Mem. geol. Surv. U.K. 139 pp.Google Scholar
MacLennan, R. M. 1954. The Liassic sequence in Morven. Trans. geol. Soc. Glasg. 21, 447–55.Google Scholar
Millot, G. 1970. The Geology of Clays. 429 pp. Paris: Masson.CrossRefGoogle Scholar
Perrin, R. M. S. 1971. The clay mineralogy of British sediments. Min. Soc. Lond. 247 pp.Google Scholar
Pierce, J. W. & Siegel, F. R. 1969. Quantification in clay mineral studies of sediments and sedimentary rocks. J. sedim. Petrol. 39, 187–93.Google Scholar
Pitman, W. C. III & Talwani, M. 1972. Sea floor spreading in the North Atlantic Ocean. Bull. geol. Soc. Am. 83, 619–46.CrossRefGoogle Scholar
Pollard, C. O. 1971. Semi displacive mechanism for diagenetic alteration of montmorillonite layers to illite layers. Spec. Pap. geol. Soc. Am. 134, 79–93.Google Scholar
Richey, J. E. & Thomas, H. H. 1930. The geology of Ardnamurchan, northwest Mull and Coll. Mem. geol. Surv. U.K. 393 pp.Google Scholar
Rodgers, J. 1970. The Tectonics of the Appalachians. 271 pp. New York: Wiley-Interscience.Google Scholar
Ross, C. S. & Shannon, E. V. 1926. The minerals of bentonite and related clays and their physical properties. Bull. Am. Ceram. Soc. 9, 77–89.Google Scholar
Sauvin, P., Esquevin, J. & Chenoux, G. 1975. Transformations induites par des intrusions doléritique dans une série argilleuse l'Ecca de Bergville (Afrique du Sud). Bull. Centre Rech. Pau SNPA 9, 261–351.Google Scholar
Schultz, C. G. 1964. Quantitative interpretation, mineralogic composition, Pierre Shale. Prof. Pap. U.S. geol. Surv. 391-C, 70 pp.Google Scholar
Shaw, H. F. 1972. The preparation of oriented clay mineral specimens for X-ray diffraction analysis by suction-onto-ceramic tile method. Clay Miner. 349–50.Google Scholar
Slaughter, M. & Earley, J. W. 1965. Mineralogy and geological significance of the Mowry bentonites, Wyoming. Spec. Pap. geol. Soc. Am. 83, 116 pp.Google Scholar
Steel, R. J., Nicholson, R. & Kalander, L. 1975. Triassic sedimentation and Palaeogeography in central Skye. Scott. J. Geol. 11, 1–13.Google Scholar
Steel, R. J. & Wilson, A. C. 1975. Sedimentation and tectonism (? Permo-Triassic) on the margin of the N. Minch Basin. Q. Jl geol. Soc. Lond. 131, 183–202.Google Scholar
Stewart, F. H. 1965. Tertiary igneous activity. In The Geology of Scotland. (ed. Craig, G. Y.). 420 pp. Edinburgh, London: Oliver and Boyd.Google Scholar
Stokke, P. R. & Carson, B. 1973. Variation in clay mineral X-ray diffraction results with the quantity of sample mounted. J. sedim. Petrol. 43, 957–64.Google Scholar
Weir, A. H., Ormerod, E. C. & El Mansey, I. M. I. 1975. Clay mineralogy of sediments of the western Nile Delta. Clay Miner. 10, 369–86.CrossRefGoogle Scholar