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First-principles study of illite–smectite and implications for clay mineral systems

Abstract

Illite–smectite interstratified clay minerals are ubiquitous in sedimentary basins and they have been linked to the maturation, migration and trapping of hydrocarbons1, rock cementation2, evolution of porewater chemistry during diagenesis3 and the development of pore pressure4. But, despite the importance of these clays, their structures are controversial. Two competing models exist, each with profoundly different consequences for the understanding of diagenetic processes: model A views such interstratified clays as a stacking of layers identical to endmember illite and smectite layers, implying discrete and independently formed units (fundamental particles)5, whereas model B views the clays as composed of crystallites with a unique structure that maintains coherency over much greater distances, in line with local charge balance about interlayers6. Here we use first-principles density-functional theory to explore the energetics and structures of these two models for an illite–smectite interstratified clay mineral with a ratio of 1:1 and a Reichweite parameter of 1. We find that the total energy of model B is 2.3 kJ atom-1 mol-1 lower than that of model A, and that this energy difference can be traced to structural distortions in model A due to local charge imbalance. The greater stability of model B requires re-evaluation of the evolution of the smectite-to-illite sequence of clay minerals, including the nature of coexisting species, stability relations, growth mechanisms and the model of fundamental particles.

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Figure 1: Fully relaxed computed structures of model A (left) and model B (right) 1:1 illite–smectite.
Figure 2: Schematic of illite-rich illite–smectite structure showing interlayer cations (spheres) and 2:1 layers.

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References

  1. Weaver, C. E. Possible uses of clay minerals in search for oil. Bull. Am. Assoc. Petrol. Geol. 44, 1505–1518 (1960)

    CAS  Google Scholar 

  2. Boles, J. R. & Franks, S. G. Clay diagenesis in Wilcox sandstones of southwest Texas—implications of smectite diagenesis on sandstone cementation. J. Sedim. Petrol. 49, 55–70 (1979)

    CAS  Google Scholar 

  3. Brown, K. M., Saffer, D. M. & Bekins, B. A. Smectite diagenesis, pore-water freshening, and fluid flow at the toe of the Nankai wedge. Earth Planet. Sci. Lett. 194, 97–109 (2001)

    Article  ADS  CAS  Google Scholar 

  4. Bethke, C. M. Inverse hydrologic analysis of the distribution and origin of Gulf Coast-type geopressured zones. J. Geophys. Res. 91, 6535–6545 (1986)

    Article  ADS  Google Scholar 

  5. Nadeau, P. H., Wilson, M. J., McHardy, W. J. & Tait, J. M. Interstratified clays as fundamental particles. Science 255, 923–925 (1984)

    Article  ADS  Google Scholar 

  6. Altaner, S. P., Weiss, C. A. & Kirkpatrick, R. J. Evidence from 29Si NMR for the structure of mixed layer illite–smectite clay minerals. Nature 331, 699–702 (1988)

    Article  ADS  CAS  Google Scholar 

  7. Brown, G. Crystal-structures of clay-minerals and related phyllosilicates. Phil. Trans. R. Soc. Lond. A 311, 221–240 (1984)

    Article  ADS  CAS  Google Scholar 

  8. Kresse, G. & Furthmüller, J. Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. Phys. Rev. B 54, 11169–11186 (1996)

    Article  ADS  CAS  Google Scholar 

  9. Stixrude, L. Talc under tension and compression: spinodal instability and structure at high pressure. J. Geophys. Res. (in the press)

  10. Berman, R. G. Internally-consistent thermodynamic data for minerals in the system Na2O-K2O-CaO-MgO-FeO-Fe2O3-Al2O3-SiO2-TiO2-H2O-CO2 . J. Petrol. 29, 445–522 (1988)

    Article  ADS  CAS  Google Scholar 

  11. Robinson, K., Gibbs, G. V. & Ribbe, P. H. Quadratic elongation—quantitative measure of distortion in coordination polyhedra. Science 172, 567–570 (1971)

    Article  ADS  CAS  Google Scholar 

  12. Smyth, J. R. & Bish, D. L. Crystal Structures and Cation Sites of the Rock-Forming Minerals (Allen and Unwin, Boston, 1988)

    Google Scholar 

  13. Rothbauer, R. Untersuchung eines 2M1-Muskovits mit Neutronenstrahlen. Neues Jb. Mineral. Mh. 4, 143–154 (1971)

    Google Scholar 

  14. Rossman, G. R. Spectroscopy of micas. Rev. Mineral. 13, 145–181 (1984)

    CAS  Google Scholar 

  15. Essene, E. J. & Peacor, D. R. Clay mineral thermometry—A critical perspective. Clays Clay Minerals 43, 540–553 (1995)

    Article  ADS  CAS  Google Scholar 

  16. Dong, H., Peacor, D. R. & Freed, R. L. Phase relations among smectite, R1 illite-smectite, and illite. Am. Mineral. 82, 379–391 (1997)

    Article  ADS  CAS  Google Scholar 

  17. Schroeder, P. A. & Irby, R. Detailed X-ray diffraction characterization of illite-smectite from an Ordovician K-bentonite, Walker County, Georgia, USA. Clay Minerals 33, 671–674 (1998)

    Article  ADS  CAS  Google Scholar 

  18. Shau, Y. H., Peacor, D. R. & Essene, E. J. Corrensite and mixed-layer chlorite/corrensite in metabasalt from northern Taiwan: TEM/AEM, EMPA, XRD, and optical studies. Contrib. Mineral. Petrol. 105, 123–142 (1990)

    Article  ADS  CAS  Google Scholar 

  19. Srodon, J., Morgan, D. J., Eslinger, E. V., Eberl, D. D. & Karlinger, M. A. Chemistry of illite/smectite and end-member illite. Clays Clay Minerals 34, 368–378 (1986)

    Article  ADS  CAS  Google Scholar 

  20. Srodon, J. Nature of mixed-layer clays and mechanisms of their formation and alteration. Annu. Rev. Earth Planet. Sci. 27, 19–53 (1999)

    Article  ADS  CAS  Google Scholar 

  21. Nadeau, P. H., Wilson, M. J., McHardy, W. J. & Tait, J. M. Interparticle diffraction: a new concept for interstratified clays. Clay Minerals 19, 757–769 (1984)

    Article  ADS  CAS  Google Scholar 

  22. Kasama, T., Murakami, T., Kohyama, N. & Watanabe, T. Experimental mixtures of smectite and rectorite: Re-investigation of “fundamental particles” and “interparticle diffraction”. Am. Mineral. 86, 105–114 (2001)

    Article  ADS  CAS  Google Scholar 

  23. Jakobsen, H. J., Nielsen, N. C. & Lindgreen, H. Sequences of charged sheets in rectorite. Am. Mineral. 80, 247–252 (1995)

    Article  ADS  CAS  Google Scholar 

  24. Altaner, S. P. & Ylagan, R. F. Comparison of structural models of mixed-layer illite-smectite and reaction mechanisms of smectite illitization. Clays Clay Minerals 45, 517–533 (1997)

    Article  ADS  CAS  Google Scholar 

  25. Ahn, J. H. & Peacor, D. R. A transmission and analytical electron microscopic study of the smectite to illite transition. Clays Clay Minerals 34, 165–179 (1986)

    Article  CAS  Google Scholar 

  26. Nadeau, P. H., Wilson, M. J., McHardy, W. J. & Tait, J. M. The conversion of smectite to illite during diagenesis: evidence from some illitic clays from bentonites and sandstones. Mineral. Mag. 49, 393–400 (1985)

    Article  CAS  Google Scholar 

  27. Hower, J., Eslinger, E. V., Hower, M. E. & Perry, E. A. Mechanism of burial metamorphism of argillaceous sediments: Mineralogical and chemical evidence. Geol. Soc. Am. Bull. 87, 725–737 (1976)

    Article  ADS  CAS  Google Scholar 

  28. Eberl, D. D., Drits, V. A. & Srodon, J. Deducing growth mechanisms for minerals from the shapes of crystal size distributions. Am. J. Sci. 298, 499–533 (1998)

    Article  ADS  CAS  Google Scholar 

  29. Monkhorst, H. J. & Pack, J. D. Special points for Brillouin-zone integrations. Phys. Rev. B 13, 5188–5192 (1976)

    Article  ADS  MathSciNet  Google Scholar 

  30. Benincasa, E., Brigatti, M. F., Medici, L. & Poppi, L. K-rich rectorite from kaolinized micaschist of the Sesia-Lanzo Zone, Italy. Clay Minerals 36, 421–433 (2001)

    Article  ADS  CAS  Google Scholar 

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Acknowledgements

This work was supported by the US National Science Foundation.

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Correspondence to Lars Stixrude.

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Stixrude, L., Peacor, D. First-principles study of illite–smectite and implications for clay mineral systems. Nature 420, 165–168 (2002). https://doi.org/10.1038/nature01155

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