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Rapid chemical analysis of the <2 μm clay fraction using an SEM/EDS technique

Published online by Cambridge University Press:  09 July 2018

T. Clayton
Affiliation:
National Oceanography Centre, University of Southampton, Waterfront Campus, European Way, Southampton, SO14 3ZH, UK
R. B. Pearce*
Affiliation:
National Oceanography Centre, University of Southampton, Waterfront Campus, European Way, Southampton, SO14 3ZH, UK
*

Abstract

Scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS) analysis of smear slides of oriented <2 mm clay fractions is shown to be a reliable and rapid analytical technique for providing chemical data on clay mineral mixtures. Such smear slides are routinely prepared for clay mineral analysis by X-ray diffraction and the only additional treatment required for chemical analysis by EDS is carbon-coating to form an electronically conductive surface. Using standard clays, mixtures of standard clays, and sediment samples, it is shown that sample thickness, sample heterogeneity and surface roughness do not introduce significant analytical errors, although the presence of non-clay mineral phases such as calcite, dolomite, quartz and pyrite may introduce minor discrepancies. Chemical data complement the XRD analyses and increase their accuracy and reliability.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2007

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