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Field emission scanning electron microscopy — a high-resolution technique for the study of clay minerals in sediments

Published online by Cambridge University Press:  09 July 2018

J. M. Huggett
Affiliation:
Department of Geology, Imperial College of Science, Technology and Medicine, London, SW7 2BP, UK
H. F. Shaw
Affiliation:
Department of Geology, Imperial College of Science, Technology and Medicine, London, SW7 2BP, UK

Abstract

The use of field emission electron microscopy for the study of clay mineral petrography in mudrocks and sandstones is discussed. The methodology including sample preparation is outlined and three examples of the application of the technique are described: the formation of authigenic illite in mudrocks, the multiple generation of authigenic illites in sandstones and the effects of KCl drilling muds on shale fabrics. In the study of authigenic illite formation in Palaeocene mudrocks from the North Sea, the FESEM analyses have demonstrated the formation of illites with increasing burial depth that conventional SEM and XRD analyses had failed to show. The FESEM analyses of the authigenic illites in Carboniferous sandstones from the southern North Sea revealed at least three different habits representing different generation episodes rather than one illite formation event.This has important repercussions with regard to the interpretation of stable isotope and dating data for the illites. Significant petrographic changes in shales after treatment with KCl drilling muds have been observed from FESEM analyses, suggesting reactivity between the shales and the KCl muds.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1997

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References

Huggett, J.M. (1995) Formation of authigenic illite in Palaeocene mudrocks from the Central North Sea: a study by high resolution electron microscopy. Clays Clay Miner. 43, 682692.CrossRefGoogle Scholar
JEOL (1994) Multipurpose digital FE SEM. Product Information Document SM21.Google Scholar
Mackinnon, I.D.R. (1990) Introduction to electron beam techniques. Pp. 2–13 in: Electron-Optical Methods in Clay Science, CMS Workshop Lectures 2 (Mackinnon, I.D.R., editor) Clay Minerals Society, Boulder, Co., USA.CrossRefGoogle Scholar
Small, J.S., Hamilton, D.L. & Habesch, S. (1992) Experimental simulation of clay precipitation within reservoir sandstones 2: mechanisms of illite formation and controls on morphology. J. Sed. Pet. 62, 520529.Google Scholar
Small, J.S. & Manning, D.A.C. (1993) Laboratory reproduction of morphological variation in petroleum reservoir clays; monitoring of fluid composition during illite precipitation. Pp. 181–212 in: Geochemistry of Clay-Pore Fluid Interactions (Manning, D.A.C., Hall, P.L. & Hughes, C.R., editors) The Mineralogical Society Series No 4, Chapman & Hall.Google Scholar