Abstract
Experimental solubility data for gibbsite and kaolinite are reviewed and applied to the problem of gibbsite stability within the natural environment. It is concluded that free alumina compounds formed (only) in lateritic soils will tend to silicify spontaneously in all sedimentary environments. This metasomatic reaction should be accompanied by massive volume expansion: unusual textures are to be anticipated.
Petrographic and field descriptions of a number of ancient kaolinitic sediments (some with, some without free alumina) are reviewed. It is concluded that silicification of hydrated aluminum oxides was an important mechanism of kaolinite formation in ancient sediments and that free alumina compounds persist only as a result of the unusual volume expansion associated with kaolinite formation.
Résumé
Les données concernant la solubilité expérimentale de la gibbsite et de la kaolinite sont passées en revue et appliquées au problème de la stabili’e de la gibbsite dans l’environnement naturel. On en conclut que les composés à alumine libre formés (seulement) dans les sols latéritiques tendront à se silicifier spontanément dans tous les environnements sédimentaires. Cette réaction métasomatique devrait être accompagnée d’une expansion massive du volume: des textures inhabituelles sont donc à attendre.
Les descriptions pétrographiques et de terrain d’un certain nombre de sédiments kaolinitiques anciens (certains avec, certains sans alumine libre) sont passées en revue. On en conclut que la silicification des oxydes d’aluminium hydrat’es a été un mécanisme important pour la formation de kaolinite dans les sédiments anciens, et que les composés à alumine libre persistent seulement en tant que résultat de l’expansion en volume inhabituelle, associée à la formation de kaolinite.
Kurzreferat
Es werden experimentelle Lòslichkeitsdaten für Gibbsit und Kaolinit überprüft und auf das Problem der Stabilität von Gibbsit in natürlicher Umgebung angewendet. Es wird der Schluss gezogen, dass (ausschliesslich) in lateritischen Böden gebildete freie Tonerdeverbindungen dazu neigen werden in allen Sedimentärumgebungen spontan zu verkieseln. Eine solche metasomatische Reaktion würde von massiver Volumenausdehnung begleitet werden. Ungewöhnliche Gefüge sind zu erwarten.
Es werden petrographische und Feldbeschreibungen einer Anzahl alter kaolinitischer Sedimente (manche mit, manche ohne freie Tonerde) überprüft. Es wird der Schluss gezogen, dass Verkieselung hydratisierter Aluminiumoxyde ein wichtiger Vorgang bei der Kaolinitbildung in alten Sedimenten war und dass freie Tonerdeverbindungen nur als eine Foloe der ungewöhnlichen, mit der Kaolinitbildung verbundenen Volumenausdehnung weiter vorhanden sind.
Резюме
Рассмотрены и применены для решения проблемы устойчивости гиббсита в природной обстановке экспериментальные данные по растворимости гиббсита и каолинита. Сделан вывод, что соединения свободного глинозема, образованные (только) в латеритовых почвах, будут иметь тенденцию к спонтанной силисификации в любой среде в осадках. Эта реакция замещения должна сопровождаться значительным увеличением объема; при этом можно ожидать появления необычных текстур.
Проанализированы петрографические данные и условия залегания ряда древних каолинитовых осадков со свободным глиноземом и без него. Авторы пришли к заключению, что силисификация гидратированных окислов алюминия является важным механизмом образования каолинита в древних осадках и что соединения свободного глинозема сохраняются только благодаря необычному увеличению объема при образовании каолинита.
Similar content being viewed by others
References
Berner, R. A. (1964) Stability fields of iron minerals in anaerobic marine sediments: J. Geol. 72, 826–834.
Biscaye, P. E. (1965) Mineralogy and sedimentation of recent deep-sea clay in the Atlantic Ocean and adjacent seas and oceans: Bull. Geol. Soc. Am. 76, 803–832.
Bouroz, A. (1964) Les composants petrographiques principaux des schistes houillers et leur signification sedimentologique: C. R. 5eCongrès. Intern. Carbonifère. Paris. 1963 pp. 289–301.
Chukhrov, F. V. (1970) Analogues of flint clays in Soviet literature: Clays and Clay Minerals 18, 1–5.
Curtis, C. D. and Brown, P. E. (1969) The metasomatic development of zoned ultrabasic bodies in Unst, Shetland: Contr. Mineral and Petrol. 24, 275–292.
Curtis, C. D. and Spears, D. A. (1968) The formation of sedimentary iron minerals: Econ. Geol. 63, 257–270.
Deer, W. A., Howie, R. A. and Zussman, J. (1962) Rock Forming Minerals. Sheet Silicates Vol. III, Longmans, London.
Eyles, V. A., Simpson, J. B. and MacGregor, A. G. (1949) Geology of Central Ayrshire: Mem. Geol. Surv. Gt. Britain.
Foose, R. (1944) High-alumina clays of Pennsylvania: Econ. Geol. 39, 557–577.
Garrels, R. M. and Christ, C. L. (1965) Solutions, Minerals and Equilibria, 450 p. Harper & Row, New York.
Hem, J. D. (1968) Graphical methods for studies of aqueous aluminum hydroxide, fluoride and sulphate complexes: U. S. Geol. Surv. Water-supply Paper 1827-B, 33p.
Hem, J. D. and Roberson, C. E. (1967) Form and stability of aluminum hydroxide complexes in dilute solution: U.S. Geol. Surv. Water-supply Paper 1827-A, 55p.
Hess, P. C. (1966) Phase equilibrium of some minerals in the K2O-Na2O-Al2O3-SiO2-H2O system at 25°C and 1 atmosphere: Am. J. Sci. 264, 289–309.
Keller, W. D. (1968) Flint clay and a flint-clay facies: Clays and Clay Minerals 16, 113–128.
Korzhinsky, D. S. (1959) Physico-chemical basis of the analysis of the paragenesis of minerals. Translated from the Russian by Consultants Bureau Inc., New York.
Lapparent, J. de (1936) Boehmite and diaspore in the bauxitic clays of Ayrshire: Sum. Prog. Geol. Surv. Gt. Britain for 1934, pt. ii, p. 1.
Price, N. B. and Duff, P. McL. D. (1969) Mineralogy and chemistry of tonsteins from Carboniferous sequences in Great Britain: Sedimentology 13, 45–69.
Reesman, A. L. and Keller, W. D. (1968) Aqueous solubility studies of high-alumina and clay minerals: Am. Mineralogist 53, 929–942.
Reesman, A. L., Pickett, E. E. and Keller, W. D. (1969) Aluminum ions in aqueous solutions: Am. J. Sci. 267, 99–113.
Richardson, G. and Francis, E. H. (1971) Fragmental clayrocks (F. C. R.) in coal bearing sequences in Scotland and north-east England: Proc. Yorks. Geol. Soc. 38, 229–260.
Roberson, C. E. and Hem, J. D. (1969) Solubility of aluminum in the presence of hydroxide, fluoride and sulphate: U.S. Geol. Surv. Water-supply Paper 1827-C, p. 37.
Schoen, R. and Roberson, C. E. (1970) Structure of aluminum hydroxides and geochemical implications: Am. Mineralogist 55, 43–77.
Smith, W. H. and O’Brien, N. R. (1965) Middle and late Pennsylvanian flint clays: J. Sediment. Petrol. 35, 610–618.
Spears, D. A. (1970) A kaolinite mudstone (tonstein) in the British coal measures: J. Sediment. Petrol. 40, 386–394.
Thompson, J. B. (1959) Local equilibrium in metasomatic processes. In Researches in Geochemistry (Edited by Abelson, P. H.), Wiley, New York.
White, D. E., Hem, J. D. and Waring, G. A. (1963) Chemical composition of subsurface waters. Chapter F, Data of Geochemistry: U.S. Geol. Sun. Prof. Paper 440-F, p. 67.
Williams, E. G. (1960) Relationship between the stratigraphy and petrography of Pottsville sandstones and the occurrence of high-alumina Mercer clay: Econ. Geol. 55, 1291–1302.
Williams, E. G., Berbenback, R. E., Falla, W. S. and Udagawa, S. (1968) Origin of some Pennsylvanian underclays in western Pennsylvania: J. Sediment. Petrol. 39, 1179–1193.
Williamson, I. A. (1970) Tonsteins —their nature, origins and uses: Mining Mag. 122, 119–125, 203–211.
Wilson, G. V. (1922) The Ayrshire bauxitic clay: Mem. Geol. Surv. Gt. Britain.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Curtis, C.D., Spears, D.A. Diagenetic Development of Kaolinite. Clays Clay Miner. 19, 219–227 (1971). https://doi.org/10.1346/CCMN.1971.0190403
Published:
Issue Date:
DOI: https://doi.org/10.1346/CCMN.1971.0190403