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Quantitative X-ray Powder Diffraction Analyses of Clays Using an Orienting Internal Standard and Pressed Disks of Bulk Shale Samples

Published online by Cambridge University Press:  01 July 2024

R. D. Cody
Affiliation:
Department of Earth Science, Iowa State University, Ames, IA 50011, U.S.A.
G. L. Thompson
Affiliation:
Department of Earth Science, Iowa State University, Ames, IA 50011, U.S.A.
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Abstract

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Quantitative analysis of clay minerals by X-ray powder diffraction requires oriented clays in order to increase detection limits of the analyses. This is achieved commonly either by smear or sedimentation techniques; however, these techniques can lead to poor analytical precision when used with an internal standard because they often produce non-homogeneous internal standard—clay mineral mixtures. Compaction of bulk shale material at 8000 psi in an hydraulic press produces preferred orientations comparable to that produced by smear or sedimentation. When used with a suitable platy internal standard which provides an estimate of clay mineral preferred orientation, excellent analytical precision is achieved routinely. Several lines of experimental evidence indicate that 1–5 µm MoS2 is an ideal orienting internal standard for use with compaction mounts.

Type
Research Article
Copyright
Copyright © 1976 The Clay Minerals Society

References

Burtner, R. L. (1974) Quantitative X-ray mineralogy—sample preparation and analysis with an aluminum internal standard: Abstracts, 23rd Ann. Clay Minerals Conf., Cleveland, Ohio.Google Scholar
Carroll, D. (1970) Clay minerals, a guide to their X-ray identification: Geol. Soc. Am., Special Paper 126, 80 pp.CrossRefGoogle Scholar
Clark, B. R. (1970), Mechanical formation of preferred orientation in clays: Am. J. Sci. 269, 250266.CrossRefGoogle Scholar
Fenner, P. and Hartung, J. R. (1969) Laboratory processing of halloysite: Clays & Clay Minerals 17, 4245.CrossRefGoogle Scholar
Gibbs, R. J. (1967) Quantitative X-ray diffraction analysis using clay minerals standards extracted from the samples to be analyzed: Clay Min. 7, 7990.CrossRefGoogle Scholar
Gibbs, R. J. (1965) Errors due to segregation in quantitative clay mineral X-ray diffraction mounting techniques: Am. Miner. 59, 741751.Google Scholar
Jackson, M. L. (1956) Soil Chemical Analysis—Advanced Course, 894 pp. Univ. Wisconsin Dept. of Soils.Google Scholar
Klug, H. P. and Alexander, L. E. (1974) X-ray Diffraction Procedures for Poly-crystalline and Amorphous Materials 966 pp. Wiley, New York.Google Scholar
Martin, R. Torrence and Ladd, C. C. (1975) Fabric of consolidated kaolinite: Clays & Clay Minerals 23, 1726.CrossRefGoogle Scholar
McCreery, G. L. (1949) Improved mount for powdered specimens used in geiger counter X-ray spectrometer: J. Am. Ceram. Soc. 32, 141146.CrossRefGoogle Scholar
Mossman, M. H., Freas, D. H. and Bailey, S. W. (1967) Orienting internal standard method for clay mineral X-ray analyses: Clays & Clay Minerals 15, 441453.CrossRefGoogle Scholar
Quakernaat, J. (1970) Direct diffractometric quantitative analysis of synthetic clay mineral mixtures with molybdenite as orientation-indicator: J. Sedim. Petrol. 40, 506513.CrossRefGoogle Scholar
Rex, R. W. and Bauer, W. R. (1965) New amine reagents for X-ray determination of expandable clays in dry samples: Clays & Clay Minerals 13, 411418.Google Scholar
Roberts, J. N. Sr. and Johnson, L. J. (1974) Soil clay mineral quantification by the internal standard X-ray diffraction method: Abstracts, 23rd Ann. Clay Minerals Conf., Cleveland, Ohio.Google Scholar
Schultz, L. G. (1955) Mineralogical particle size variations in oriented clay aggregates: J. Sedim. Petrol. 25, 124125.CrossRefGoogle Scholar
Schultz, L. G. (1964) Quantitative interpretation of mineralogical composition from X-ray and chemical data for the Pierre Shale: U.S. Geol. Survey, Prof. Paper 291–C, 31 pp.CrossRefGoogle Scholar
Tchalenko, J. S., Burnett, A. D. and Hung, J. J. (1971) The correspondence between optical and X-ray measurements of particle orientation in clays: Clay Min. 9, 4770.CrossRefGoogle Scholar
Towe, K. M. (1974) Quantitative clay petrology; the trees but not the forest? Clays & Clay Minerals 22, 275278.CrossRefGoogle Scholar
van der Marel, H. W. (1960) Quantitative analysis of kaolinites: Silicates industriels 25, 2531; 76–78.Google Scholar