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Application of backscattered electron microscopy in shale petrology

Published online by Cambridge University Press:  01 May 2009

D. H. Krinsley
Affiliation:
Department of Geology, Arizona State University, Tempe, AZ 85287, USA
K. Pye
Affiliation:
Department of Earth Sciences, Downing Street, Cambridge CB2 3EQ, England
A. T. Kearsley
Affiliation:
Department of Geology and Physical Sciences, Oxford Polytechnic, Headington Hill, Oxford

Summary

A grey pyritic mudstone from Central Wales (Red Vein unit of the Dicellograptus anceps zone, Upper Ordovician Ashgill) has been examined in thin section by scanning electron microscopy using backscattered electrons. Using backscatter it is possible to identify individual mineral constituents of the mudstone by virtue of their atomic number (Z) contrast and differential hardness (relief). The amount of detail observable is far greater than that possible with optical microscopy. Valuable information can be obtained relating to particle form, orientation, texture and internal structure which aids in interpretation of the deformational and diagenetic history of the rock. The adoption of electron microscopical methods in the study of thin sections and polished rock chip surfaces promises to revolutionize the field of shale petrology.

Type
Articles
Copyright
Copyright © Cambridge University Press 1983

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