Hostname: page-component-78c5997874-v9fdk Total loading time: 0 Render date: 2024-11-05T09:29:51.199Z Has data issue: false hasContentIssue false

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

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

Boyd, F.R., Finger, L.W. & Chayes, F. (1969) Computer reduction of electron probe data. Carnegie Institute of Washington Year Book, 67, 210215.Google Scholar
Croudace, I.W. & Robinson, N.D. (1983) Asimple, rapid and precise method for the preparation of oriented clay mounts. Clay Minerals, 18, 337340.CrossRefGoogle Scholar
Gibbs, R.J. (1965) Error due to segregation in quantitative clay mineral X-ray diffraction mounting techniques. American Mineralogist, 50, 741751.Google Scholar
Gold, C.M., Cavell, P.A. & Smithy, D.G.W. (1983) Clay minerals in mixtures: sample preparation, analysis, and statistical interpretation. Clays and Clay Minerals, 31, 191199.CrossRefGoogle Scholar
Hathon, E.G. & Underwood, M.B. (1991) Clay mineralogy and chemistry as indicators of hemipelagic sediment dispersal south of the Aleutian arc. Marine Geology, 97, 145166.Google Scholar
Heath, G.R. & Pisias, N.G. (1979) Amethod for the quantitative estimation of clay minerals in North Pacific deep sea sediments. Clays and Clay Minerals, 27, 175184.Google Scholar
Hillier, S. & Clayton, T. (1992) Cation exchange ‘staining’ of clay minerals in thin-section for electron microscopy. Clay Minerals, 27, 379384.Google Scholar
Jenkins, R. (1999) X-ray Fluorescence Spectrometry (2nd edition). Wiley, New York.CrossRefGoogle Scholar
Kawano, M. & Tomita, K. (2001) Microbial biomineralization in weathered volcanic ash deposit and formation of biogenic minerals by experimental incubation. American Mineralogist, 86, 400410.Google Scholar
Potts, P.J., Tindle, A.G. & Isaacs, M.C. (1983) On the precision of electron microprobe data: a new test for the homogeneity of mineral standards. American Mineralogist, 68, 12371242.Google Scholar
Ross, L.M., Zhao, N. & Johns, W.D. (1993) Quantitative X-ray microanalysis of oriented clay minerals: an SEM/EDS technique to determine major element chemistry. Proceedings of the Clay Mineral Society, 8, 52.Google Scholar
Spiers, G.A., Dudas, M.J. & Hodgins, L.W. (1983) Simultaneous multielement analysis of clays by inductively coupled plasma-atomic emission spectroscopy using suspension aspiration. Clays and Clay Minerals, 31, 397400.Google Scholar
Tingle, T.N., Neuhoff, P., Ostgergren, P., Jones, R.E. & Donovan, J.J. (1996) The effect of ‘missing’ unanalyzed oxygen on quantitative electron probe microanalysis of hydrous silicate and oxide minerals. Geological Society of America Abstracts, 28, 212.Google Scholar
Underwood, M.B. & Deng, X. (1997) Clay mineralogy and clay geochemistry in the vicinity of the décollement zone, northern Barbados Ridge. Pp. 329 in: Proceedings of the Ocean Drilling Program, Scientific Results (Shipley, T.H., Ogawa, Y., Blum, P. & Bahr, J.M., editors), 156.Google Scholar
Ziebold, T.O. (1967) Precision and sensitivity in electron microprobe analysis. Analytical Chemistry, 39, 859861.CrossRefGoogle Scholar