Abstract
A technique was developed to determine the low contents of smectite layers in the dispersed dioctahedral K-bearing micaceous minerals of the illite-glauconite composition. To implement this technique, diffraction patterns were calculated for two-component mixed-layer mica-smectite structures, in which the content of smectite layers increased with a step of 2% from 2 to 20% at a short-range order factor R = 0 and from 2 to 14% at R = 1. On the basis of Mering’s principles (1949) and Q-rules (Moore and Reynolds, 1989), the half-width βcosθ of each basal refection and its distance Q to the nearest reflection corresponding to the periodical structure made up of 9.98 Å micaceous layers were calculated for mixed-layer structures with the given content of smectite layers W Sm. The Q dependence on βcosθ for the series of basal reflections observed in the calculated diffraction pattern was approximated by a straight line corresponding to the linear regression equation. Equations relating slope angles of straight line (α) and concentrations of smectite layers (W Sm) were deduced for the analyzed mixed-layer structures with the short-range order factors R = 0 and R = 1, respectively. To determine the contents of smectite layers in natural micaceous varieties, the basal reflections observed in experimental patterns from the oriented ethylene glycol-saturated samples were subjected to the following procedures: (1) determination of the half-width (βcosθ)e of each 00l reflection of the analyzed sample and plotting Q dependence on (βcosθ)e for the observed series of basal reflections, with its further approximation by the linear regression equation and the corresponding straight line; (2) calculation of the slope angle of this straight line α and determination of the content of smectite layers in the sample structure using the equation relating α and W Sm. Application of the described procedure showed that the content of smectite layers in the studied samples varied from 5.2 to 12.6%. The content of smectite layers was determined accurate to a few tenths of a percent. Since the half-width of reflection 003 does not depend on the content of smectite layers, its value was used to determine the thickness and number of layers in the averaged CSD of the studied sample. XRD patterns calculated for mixed-layer structures with experimentally determined W Sm, W Mc, R, T, and N parameters are in a good agreement with experimental patterns of the studied samples.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Drits, V.A. and Sakharov, B.A., Rentgenostrukturnyi analiz smeshanosloinykh mineralov (The X-Ray Structural Analysis of Mixed-Layer Minerals), Moscow: Nauka, 1976.
Drits, V.A. and Tchoubar, C., X-ray diffraction by disordered lamellar structures, New York: Springer, 1990.
Drits, V.A. and Kossovskaya, A.G., Glinistye mineraly: smektity, smeshanosloinye obrazovaniya (Clay Minerals: Smectites and Mixed-Layer Varieties), Moscow: Nauka, 1990.
Drits, V.A. and Kossovskaya, A.G., Glinistye mineraly: slyudy, khlority (Clay Minerals: Micas and Chlorites), Moscow: Nauka, 1991.
Drits, V.A., Kameneva, M.Yu., Sakharov, B.A., et al., Problemy opredeleniya real’noi struktury glaukonitov i rodstvennykh tonkodispersnykh fillosilikatov (Problems of Determination of the Real Structure of Glauconites and Related Fine-Dispersed Phyllosilicates), Novosibirsk: Nauka, 1993.
Drits, V.A., Varaxina, T.V., Sakharov, B.A., and Planćon, A., A simple technique for identification of one-dimensional powder X-ray diffraction patterns for mixed-layer illitesmectites and other interstratified minerals, Clays Clay Miner., 1994, vol. 42, pp. 382–390.
Drits, V.A., Środoń, J., and Eberl, D.D., XRD measurements of mean crystallite thickness of illite and illite/smectite: Reappraisal of the Kubler index and the Scherrer equation, Clays Clay Miner., 1997a, vol. 45, pp. 461–475.
Drits, V.A., Sakharov, B.A., Lindgreen, H., and Salyn, A., Sequential structural transformation of illite-smectite-vermiculite during diagenesis of Upper Jurassic shales from North Sea and Denmark, Clay Miner., 1997b, vol. 32, pp. 351–371.
Drits, V.A., Sakharov, B.A., Dainyak, L.G., et al., Structural and chemical heterogeneity of illite-smectites from Upper Jurassic mudstones of East Greenland related to volcanic and weathered parent rocks, Am. Miner., 2002a, vol. 87, no. 12, pp. 1590–1607.
Drits, V.A., Lindgreen, H., Sakharov, B.A., et al., Tobelitization of smectite during oil generation in oil-source shales. Application to North Sea illite-tobelite-smectite-vermiculite, Clays Clay Miner., 2002b, vol. 50, pp. 82–98.
Drits, V.A., Sakharov, B.A., A.L. Salyn, and H. Lindgreen, Determination of the content and distribution of fixed ammonium in illite-smectite using a modified X-ray diffraction technique: Application to oil source rocks of western Greenland, Am. Miner., 2005, vol. 90, pp. 71–84.
Drits, V.A., Zviagina, B.B., McCarty, D.K., and Salyn, A.L., Factors responsible for crystal-chemical variations in the solid solutions from illite to aluminoceladonite and from glauconite to celadonite, Am. Miner., 2010, vol. 95, pp. 348–361.
Drits, V.A., Ivanovskaya, T.A., Sakharov, B.A., et al., Nature of the Structural and Crystal-Chemical Heterogeneity of the Mg-Rich Glauconite (Riphean, Anabar Uplift), Lithol. Miner. Resour., 2010, no. 6, pp. 555–567.
Drits, V.A, Ivanovskaya, T.A., Sakharov, B.A., et al., Mixed-Layer Corrensite-Chlorites and Their Formation Mechanism in the Glauconitic Sandstone-Clayey Rocks (Riphean, Anabar Uplift), Lithol. Miner. Resour., 2011, no. 6, pp. 566–593.
Guinier, A., Theorie et technique de la radiocristallographie, Paris: Dunod, 1964.
Ivanovskaya, T.A., Zaitseva, T.S., Zvyagina, B.B., and Sakharov, B.A., Crystal-Chemical Peculiarities of Globular Layer Silicates of the Glauconite-Illite Composition (Upper Proterozoic, Northern Siberia), Lithol. Miner. Resour., 2012, no. 6, pp. 499–520.
Lanson, B., Sakharov, B.A., Claret, F., and Drits, V.A., Diagenetic smectite-to-illite transition in clay-rich sediments: a reappraisal of X-ray diffraction results using the multi-specimen method, Am. J. Sci., 2009, vol. 309, no. 6, pp. 476–516.
Lindgreen, H., Drits, V.A., Sakharov, B.A., et al., The structure and diagenetic transformation of illite-smectite and chlorite-smectite from North Sea Cretaceous-Tertiary chalk, Clay Miner., 2002, vol. 37, pp. 429–450.
Lindgreen, H., Drits, V.A., Jakobsen, F.C., and Sakharov, B.A., Clay mineralogy of the Central North Sea Upper Cretaceous-Tertiary chalk and formation of clay rich layers, Clays Clay Miner., 2008, vol. 56, pp. 693–710.
McCarty, D.K., Sakharov, B.A., and Drits, V.A., Early clay diagenesis in Gulf Coast sediments: new insights from XRD profile modeling, Clays Clay Miner., 2008, vol. 56, no. 3, pp. 359–379.
McCarty, D.K., Sakharov, B.A., and Drits, V.A., New insights into smectite illitization: A zoned K-bentonite revisited, Am. Miner., 2009, vol. 94, pp. 1653–1671.
Mering, J., L’interference des Rayons X dans les systems a stratification desordonnee, Acta Crystallogr., 1949, vol. 2, pp. 371–377.
Moore, D.M. and Reynolds, R.C., Jr., X-Ray Diffraction and the Identification and Analysis of Clay Minerals, Oxford: Oxford Univ. Press, 1989.
Moore, D.M. and Reynolds, R.C., Jr., X-Ray Diffraction and the Identification and Analysis of Clay Minerals, Oxford: Oxford Univ. Press, 1997.
Reynolds, R.C., Jr., and Hower, J., The nature of interlayering in mixed-layer illite-montmorillonites, Clays Clay Miner., 1970, vol. 18, pp. 25–36.
Reynolds, R.C., Interstratified clay minerals, in Crystal Structures of the Clay Minerals and Their X-Ray Identification, Brindley, G.W. and Brown, G., Eds., London: Miner. Soc., 1980, pp. 249–303.
Reynolds, R.C., NEWMOD, a Computer Program for the Calculation of One-Dimensional Diffraction Patterns for Mixed-Layered Clays, Reynolds, R.C., Ed., Hanover: New Hampshire, 1985.
Reynolds, R.C., The Lorentz-polarization factor and preferred orientation in oriented clay aggregates, Clays Clay Miner., 1986, vol. 34, pp. 359–367.
Reynolds, R.C., Mixed-layer chlorite minerals, in Hydrous Phyllosilicates. Reviews in Mineralogy, Washington, DC: Miner. Soc. Am., 1988, vol. 19, pp. 601–609.
Sakharov, B.A., Besson, G., Drits, V.A., Kameneva, M.Yu., Salyn, A.L., and Smoliar, B.B., X-ray study of the nature of stacking faults in the structure of glauconites, Clays Clay Miner., 1990, vol. 25, pp. 419–435.
Sakharov, B.A. and Lanson, B., X-ray identification of mixed-layer structures, in Handbook of Clay Science, Part B. Techniques and Applications, Bergaya, F. and Lagaly, G., Eds., Amsterdam: Elsevier, 2013, Chapter 2.3 (Modeling of Diffraction Effects), pp. 51–135.
Sakharov, B.A., Lindgreen, H., Salyn, A.L., and Drits, V.A., Determination of illite-smectite structures using multispecimen X-ray diffraction profile fitting, Clays Clay Miner., 1999, vol. 47, pp. 555–566.
Środoń, J., Precise identification of illite-smectite interstratification by X-ray powder diffraction, Clays Clay Miner., 1980, vol. 28, pp. 401–411.
Środoń, J., X-ray identification of randomly interstratified illite/smectite in mixtures with discrete illite, Clay Miner., 1981, vol. 16, pp. 297–304.
Środoń, J., X-ray powder diffraction identification of illitic materials, Clays Clay Miner., 1984, vol. 32, pp. 337–349.
Środoń, J., Use of clay minerals in reconstructing geological processes: recent advances and some perspectives, Clay Miner., 1999, vol. 47, pp. 27–37.
Środoń, J. and Eberl, D., Illite, in Micas. Reviews in Mineralogy, Washington, DC: Miner. Soc. Am., 1984, vol. 13, pp. 495–544.
Środoń, J., Morgan, D.J., Eslinger, E.V., et al., Chemistry of illite/smectite and end-member illite, Clays Clay Miner., 1986, vol. 34, pp. 368–378.
Watanabe, T., Identification of illite/montmorillonite interstratifications by X-ray powder diffraction, J. Miner. Soc. Jap. Spec. Iss., 1981, vol. 15, no. pp. 32-41.
Wojdyr, M., Fityk: a general-purpose peak fitting program, J. Appl. Crystallogr., 2010, vol. 43, pp. 1126–1128.
Author information
Authors and Affiliations
Corresponding author
Additional information
Original Russian Text © B.A. Sakharov, V.A. Drits, 2015, published in Litologiya i Poleznye Iskopaemye, 2015, No. 1, pp. 55–86.
Rights and permissions
About this article
Cite this article
Sakharov, B.A., Drits, V.A. Technique for determination of the content of smectite layers in the dispersed dioctahedral K-bearing micaceous minerals. Lithol Miner Resour 50, 50–79 (2015). https://doi.org/10.1134/S0024490215010058
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1134/S0024490215010058