Hostname: page-component-cd9895bd7-7cvxr Total loading time: 0 Render date: 2024-12-25T06:10:59.064Z Has data issue: false hasContentIssue false
  • English
  • Français

Quantitative X-Ray Determinations of Some Aluminous Clay Minerals in Rocks

Published online by Cambridge University Press:  01 January 2024

Leonard G. Schultz
Leonard G. Schultz*
Affiliation:
U.S. Geological Survey, Denver, Colorado, USA
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

x-ray diffraction traces were made of oriented aggregates of artificial binary mixtures containing approximately equal, weighed amounts of samples of illite, montmorillonite, mixed-layered combinations of illite and montmorillonite, and of kaolinite samples having different degrees of crystallinity. Measurements most suitable for quantitative purposes were obtained from the 7 Å kaolinite peaks and from the 10 Å peaks of illite and collapsed montmorillonite and collapsed mixed-layer clay. In this paper the sum of five height measurements at half-degree intervals across the peak are considered to be a measure of the area of the peak. Fireclay-type kaolinites gave 7 Å peak areas about equal to the area of the 10 Å peak of an equal amount of illite, montmorillonite, or mixed-layer clay, whereas well-crystallized kaolinites gave 7 Å peak areas generally about twice that of the 10 Å peak of an equal weight of the illite-montmorillonite minerals. Kaolinite samples having intermediate degrees of crystallinity gave 7 Å/10 Å peak area ratios intermediate between 1: 1 and 2:1. The shape of the 7 Å kaolinite peak was used to evaluate the crystallinity of the kaolinite.

x-ray diffraction characteristics of the chlorite minerals from the different groups of sedimentary rocks studied vary considerably, and no uniform method has been found for their evaluation.

Type
Article
Information
Clays and Clay Minerals (National Conference on Clays and Clay Minerals) , Volume 7 , February 1958 , pp. 216 - 224
Copyright
Copyright © Clay Minerals Society 1958

Footnotes

Publication authorized by the Director, U.S. Geological Survey.

References

Brindley, G. W. (Editor) (1951) X-ray Identification and Crystal Structures of Clay Minerals: Mineralogical Society, London, 345 pp.Google Scholar
Johns, W. D., Grim, R. E. and Bradley, W. F. (1954) Quantitative estimations of clay minerals by diffraction methods: J. Sed. Petrol., v. 24, no. 4, pp. 242–251.Google Scholar
Kinter, E. B. and Diamond, S. (1956) A new method for preparation and treatment of oriented-aggregate specimens of soil clays for x-ray diffraction analysis: Soil Sci., v. 81, no. 2, pp. 111–120.CrossRefGoogle Scholar
Murray, H. H. (1954) Genesis of clay minerals in some Pennsylvanian shales of Indiana and Illinois: in Clays and Clay Minerals, Natl. Acad. Science—Natl. Research Council, publ. 327, pp. 47–67.Google Scholar
Schultz, L. G. (1955) Quantitative evaluation of the kaolinite and illite in underclays: in Clays and Clay Minerals, Natl. Acad. Science—Natl. Research Council, pub. 395, pp. 421–429.Google Scholar
Talvenheimo, G. and White, J. L. (1952) Quantitative analysis of clay minerals with the x-ray spectrometer: Analyt. Chem., v. 24, no. 11, pp. 1784–1789.CrossRefGoogle Scholar
Weaver, C. E. (1958) Geologic interpretation of argillaceous sediments. I. Origin and significance of clay minerals in sedimentary rocks: Bull. Amer. Assoc. Petrol. Geologists, v. 42, no. 2, pp. 254–271.Google Scholar