Hostname: page-component-586b7cd67f-t7czq Total loading time: 0 Render date: 2024-11-25T23:17:23.263Z Has data issue: false hasContentIssue false
  • English
  • Français

K/Ar Systematics of an Acid-Treated Illite/Smectite: Implications for Evaluating Age and Crystal Structure

Published online by Cambridge University Press:  02 April 2024

James L. Aronson  and
C. B. Douthitt
James L. Aronson
Affiliation:
Case Western Reserve University, Cleveland, Ohio 44106
C. B. Douthitt*
Affiliation:
Case Western Reserve University, Cleveland, Ohio 44106
*
1Present address: Geology Department, Melbourne University, Parkville, Victoria 3052, Australia.
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.

On the basis of progressive acid dissolution the Thompson-Hower model states that mixed-layer glauconite/smectite and illite/smectite contain potassium in two structural sites: a mica-type K position (site 1) and a position of uncertain structural status more prone to dissolution (site 2). Site 2 was thought not to retain radiogenic argon (40Ar*). Using extensive progressive acid dissolution and K/Ar studies on a sized illite/smectite (I/S), determining the amount of K in site 2 is shown to be somewhat more complicated than previously thought because the dissolution pattern depends on acid normality. More important, site 2 fully retains 40Ar*, and no age correction is thus necessary as is required by the Thompson-Hower model, further affirming the geochronologic value of illite in mixed-layer clay. These data are also relevant to understanding the crystal and particle structure of I/S. Site 2 is probably a partly filled K interlayer that develops as an intermediate kinematic step on the way to being fully filled during the transformation of smectite to illite.

Keywords

Acid dissolutionAge datingGlauconiteIllite/smectiteInterstratificationOrderingPotassium
Type
Research Article
Information
Clays and Clay Minerals , Volume 34 , Issue 4 , August 1986 , pp. 473 - 482
Copyright
Copyright © 1986, The Clay Minerals Society

References

Altaner, P., Hower, J., Whitney, G. and Aronson, J., 1984 Model for K-bentonite formation: evidence from zoned K-bentonites in the disturbed belt, Montana Geology 12 412–415.2.0.CO;2>CrossRefGoogle Scholar
Aronson, J. and Hower, J., 1976 The mechanism of burial metamorphism of argillaceous sediments 2. Radiogenic argon evidence Geol. Soc. Amer. Bull. 87 738–744.2.0.CO;2>CrossRefGoogle Scholar
Brindley, G. and Youell, R., 1951 A chemical determination of “tetrahedral” and “octahedral” aluminum ions in a silicate Acta Crystallogr. 4 495–496.CrossRefGoogle Scholar
Bystrom, A. M. (1956) Mineralogy and petrology of the Ordovician bentonite beds at Kinnekule, Sweden: Sveriges Geol. Undersokn. Arsbok 48, 62 pp.Google Scholar
Eslinger, E., Highsmith, P., Albers, D. and de Mayo, B., 1979 Role of iron reduction in the conversion of smectite to illite in bentonites in the Disturbed Belt, Montana Clays & Clay Minerals 27 327–338.CrossRefGoogle Scholar
Grandquist, W., Sumner, G. and Swineford, A., 1957 Acid dissolution of a Texas bentonite Clays and Clay Minerals, Proc. 6th Natl. Conf., Berkeley, California, 1957 New York Pergamon Press 292–301.Google Scholar
Hoffman, Jane, 1976 Regional metamorphism and K-Ar dating of clay minerals in Cretaceous sediments of the disturbed belt of Montana .Google Scholar
Hoffman, J., Hower, J. and Aronson, J., 1976 Radiometric dating of time of thrusting in the disturbed belt of Montana Geology 4 16–20.2.0.CO;2>CrossRefGoogle Scholar
Inoue, A. and Utada, M., 1983 Further investigations of a conversion series of dioctahedral mica/smectites in the Shinzan hydrothermal alteration area, northeast Japan Clays & Clay Minerals 31 401–412.CrossRefGoogle Scholar
Morton, J. P., 1985 Rb-Sr evidence for punctuated illite-smectite diagenesis in the Oligocene Frio Formation, Texas Gulf Coast Geol. Soc. Amer. Bull. 96 114–122.2.0.CO;2>CrossRefGoogle Scholar
Nadeau, P. H. and Reynolds, R.C., 1981 Burial and contact metamorphism in the Mancos Shale Clays & Clay Minerals 29 249–259.CrossRefGoogle Scholar
Nadeau, P. H., Tait, J. M., McHardy, W. J. and Wilson, M. J., 1984 Interstratified XRD characteristics of physical mixtures of elementary clay particles Clay Miner. 19 67–76.CrossRefGoogle Scholar
Nadeau, P. H., Wilson, M. J., McHardy, W. J. and Tait, J. M., 1984 Interstratified clays as fundamental particles Science 225 923–925.CrossRefGoogle ScholarPubMed
Odin, G. and Hunziker, J., 1974 Etude isotopique de l’alteration naturelle d’une formation a glauconie (methode a l’argon) Contrib. Mineral. Petrol. 48 9–22.CrossRefGoogle Scholar
Odin, G., Rex, D. and Odin, G., 1982 Potassium-argon dating of washed, leached, weathered and reworked glauconites Numerical Dating in Stratigraphy New York Wiley 362–385.Google Scholar
Osthaus, B., 1956 Kinetic studies on montmorillonites and nontronites by the acid dissolution techniques Clays & Clay Minerals 18 25–36.Google Scholar
Reynolds, R. C. and Hower, J., 1970 The nature of inter-layering in mixed layer illite-montmorillonites Clays & Clay Minerals 18 25–36.CrossRefGoogle Scholar
Ross, G. S., 1969 Acid dissolution of chlorites: release of magnesium, iron, and aluminum and mode of acid attack Clays & Clay Minerals 17 347–354.CrossRefGoogle Scholar
Środoń, J., Eberl, D. D. and Bailey, S. W., 1984 Illite Micas, Reviews in Mineralogy 13 Washington, D. C. Mineralogical Society of America 495–544.Google Scholar
Steiger, R. and Jager, E., 1977 Subcommission on geochronology: convention on the use of decay constants in geo- and cosmochronology Earth Planet. Sci. Lett. 36 359–362.CrossRefGoogle Scholar
Thompson, G. and Hower, J., 1973 An explanation for the low radiometric ages from glauconite Geochim. Cosmochim. Acta 37 1473–1491.CrossRefGoogle Scholar
Thompson, G. and Hower, J., 1975 The mineralogy of glauconite Clays & Clay Minerals 23 289–300.CrossRefGoogle Scholar