Home InterstratiÞ ed kaolinite-smectite: Nature of the layers and mechanism of smectite kaolinization
Article
Licensed
Unlicensed Requires Authentication

InterstratiÞ ed kaolinite-smectite: Nature of the layers and mechanism of smectite kaolinization

  • Teresa Dudek EMAIL logo , Javier Cuadros and Saverio Fiore
Published/Copyright: March 31, 2015
Become an author with De Gruyter Brill

Abstract

This study aims to contribute to a better understanding of the nature and evolution mechanism of interstratified clay minerals. We examined the <2 μm or <0.2 μm size fraction of interstratified kaolinite- smectite (K-S) formed by hydrothermal and hydrogenic alteration of volcanogenic material from a Tortonian clay deposit (Almería, Spain), a weathered Eocene volcanic ash (Yucatan, Mexico), and a weathered Jurassic bentonite (Northamptonshire, England). The methods used were X-ray diffraction analysis (XRD) of random and oriented preparations, thermogravimetry, chemical analysis, and 29Si MAS nuclear magnetic resonance. The proportions of kaolinite and smectite in K-S (%K) were determined by fitting the XRD patterns of ethylene-glycol-saturated samples with patterns calculated with the NEWMOD computer program. The obtained range of compositions is 0.85%K. A comparison of the results from the various techniques showed non-linear relationships, indicating that the layers in K-S are complex and hybrid in nature. The smectite-to-kaolinite reaction is a solid-state transformation proceeding through formation of kaolinite-like patches within the smectite layers. The process consists of several non-simultaneous stages: (1) removal of parts of the tetrahedral sheet, resulting in formation of kaolinite-like patches; (2) layer collapse to ~7 Å where the kaolinite-like patches are sufficiently large; (3) Al for Mg substitution in the octahedral sheet, simultaneous or slightly delayed with respect to layer collapse, causing a layer-charge decrease and loss of interlayer cations; (4) Si for Al replacement in the tetrahedral sheet and further loss of interlayer cations. Iron remains in the kaolinite or is lost at the latest stages of the process.

Received: 2005-1-13
Accepted: 2005-6-6
Published Online: 2015-3-31
Published in Print: 2006-1-1

© 2015 by Walter de Gruyter Berlin/Boston

Articles in the same Issue

  1. Dana Lecture. Rates of Fe, Mg, Mn, and Ca diffusion in garnet
  2. An FTIR study of hydrogen in anorthoclase and associated melt inclusions
  3. First occurrence of iodine in natural sulfosalts: The case of mutnovskite, Pb2AsS3(I,Cl,Br), a new mineral from the Mutnovsky volcano, Kamchatka Peninsula, Russian Federation
  4. The real topological conÞ guration of the extra-framework content in alkali-poor beryl: A multi-methodological study
  5. A low-temperature heat-capacity study of synthetic anhydrous Mg-cordierite (Mg2Al4Si5O18)
  6. Dissolution kinetics of pyrochlore ceramics for the disposition of plutonium
  7. Oxy-amphibole equilibria in Ti-bearing calcic amphiboles: Experimental investigation and petrologic implications for mantle-derived amphiboles
  8. Fe2+/Fe3+ charge ordering in contact layers of lamellar magnetism: Bond valence arguments
  9. Calcic amphibole growth and compositions in calc-alkaline magmas: Evidence from the Motru Dike Swarm (Southern Carpathians, Romania)
  10. Anomalously high Fe contents in rehomogenized olivine-hosted melt inclusions from oxidized magmas
  11. The rate of ferrihydrite transformation to goethite via the Fe(II) pathway
  12. Phase transitions and volumetric properties of cryolite, Na3AlF6: Differential thermal analysis to 100 MPa
  13. The crystal structure of dissakisite-(La) and structural variations after annealing of radiation damage
  14. Effects of metal protection coils on thermocouple EMF in multi-anvil high-pressure experiments
  15. First-principles study of the OH-stretching modes of gibbsite
  16. In situ X-ray diffraction study of phase transitions of FeTiO3 at high pressures and temperatures using a large-volume press and synchrotron radiation
  17. High-pressure proton disorder in brucite
  18. Microhardness, toughness, and modulus of Mohs scale minerals
  19. Effects of pH, temperature, and aqueous organic material on the dissolution kinetics of meta-autunite minerals, (Na, Ca)2-1[(UO2)(PO4)]2⋅3H2O
  20. InterstratiÞ ed kaolinite-smectite: Nature of the layers and mechanism of smectite kaolinization
  21. The kinetics of the α → β transition in synthetic nickel monosulÞ de
  22. An electron microprobe analysis, secondary ion mass spectrometry, and single-crystal X-ray diffraction study of phlogopites from Mt. Vulture, Potenza, Italy: Consideration of cation partitioning
  23. Unique W-rich alloy of Os and Ir and associated Fe-rich alloy of Os, Ru, and Ir from California
  24. Schreyerite, V2Ti3O9: New occurrence and crystal structure
  25. A cold-sealing capsule design for synthesis of fluid inclusions and other hydrothermal experiments in a piston-cylinder apparatus
  26. Complete solid-solution between Na3Al2(PO4)3 and Mg3Al2(SiO4)3 garnets at high pressure
Downloaded on 6.10.2025 from https://www.degruyterbrill.com/document/doi/10.2138/am.2006.1897/html
Scroll to top button