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Clays and Clay Minerals

, Volume 33, Issue 2, pp 99–106 | Cite as

Mineralogy, Crystallinity, O18/O16, and D/H of Georgia Kaolins

  • Ali Asghar Hassanipak
  • Eric Eslinger
Article

Abstract

Mineralogy, kaolin crystallinity, Fe content, δO18, and δD were determined for late Cretaceous “soft” and early Tertiary “hard” Georgia kaolins. The crystallinity of the <0.5-, 0.5–1.0-, and 1.0–2.0- µm size fractions of soft kaolins was higher than that of equivalent size fractions of hard kaolins. δO18 and δD of the soft and hard kaolins ranged between 18.5 to 23.1‰, and −64 to −41‰, respectively, and could not be used to discriminate soft from hard kaolins. The trends of crystallinity vs. δO18 were different for kaolins collected at different localities, and, for a given sample, δO18 generally decreased with increasing crystallinity and with increasing crystallite size. These data indicate that the Tertiary kaolins could not have been simply derived from the Cretaceous kaolins by winnowing unless post-sedimentation recrystallization of one or both occurred. δD vs. δO18 systematics indicate that the late Cretaceous to early Tertiary Georgia kaolins crystallized over a temperature range of about 15°C in the presence of waters that varied little in isotopic composition.

Key Words

Crystallinity Hardness Isotope Kaolin Origin Oxygen isotopes 

Резюме

Были определены минералогия, степень кристаллизации каолина, содержание Fе, δО18, и δD для “мягкого” позднемелового и “твердого” раннетретичного джорджийских каолинов. Кристальность фракций мягких каолинов размером <0,5-, 0,5-1,0-, и 1,0–2,0-рт была выше, чем кристальной» эквивалентных по размеру фракций твердых каолинов. δО18 и δD мягких и твердых каолинов колебались от 18,5 до 23,1% и от 64% до 41% соответственно и не могли быть использованы для распознавания мягких каолинов от твердых. Характер зависимости кристальности от δО18 был разный для каолинов, отобранных из разных мест, и для данного образца δО18 в основном уменьшается при увеличении кристальности и при увеличении размера кристаллитов. Эти данные указывают на то, что третичные каолины не могли просто формироваться из меловых каолинов путем механического фракционирования пока не произошла послеседиментационная перекристаллизация одного типа или обоих. δD в зависимости от δО18 показывают, что позднемеловые и раннетретичные каолины кристаллизировались в диапазоне изменений температуры около 15°С в присутствии вод, незначительно отличающихся по составу изотопов. [Е.G.]

Resümee

Es wurde die Mineralogie, die Kaolinkristallinität, der Fe-Gehalt, die δO18- und δD-Werte an “weichen” Georgia-Kaolinen aus der späten Kreide und an “harten” Georgia-Kaolinen aus dem frühen Tertiär untersucht. Die Kristallinität der weichen Kaoline der Fraktionen <0,5; 0,5–1,0, und 1,0–2,0 µm war besser als die der entsprechenden Kornfraktionen der harten Kaoline. δO18 und δD der weichen und harten Kaoline lag zwischen 18,5 und 23,1‰ bzw. zwischen −64 bis −41‰ und konnte nicht zur Unterscheidung zwischen weichem und hartem Kaolin verwendet werden. Wurde die Kristallinität gegen δO18 aufgetragen, so waren die Trands für Kaoline von verschiedenen Vorkommen verschieden, und—bei einer gegebenen Probe—nahm der δO18-Wert im allgemeinen mit zunehmender Kristallinität und mit zunehmender Kristallgröße ab. Diese Daten deuten darauf hin, daß die tertiären Kaoline nicht einfach durch Sortierung aus den Kaolinen der Kreide entstanden sein können, ohne daß eine postsedimentäre Rekristallisation des einen oder beider Kaoline eintrat. Darstellungen von δD gegen δO18 zeigen, daß die spätkretazischen bis frühtertiären Georgia-Kaoline über einen Temperaturbereich von etwa 15üC in Gegenwart von Wässern kristallisierten, die in ihrer Isotopenzusammensetzung in geringem Maße variierten. [U.W.]

Résumé

On a déterminé la minéralogie, la cristallinité de Kaolin, le contenu en Fe, δO18, et δD pour des kaolins de Georgie “mous” du bas Crétacé et “durs” du haut Tertiaire. La cristallinité de fractions de taille <0,5, 0,5–1,0 et 1,0–2,0 µm de kaolins mous était plus élevée que celle de fractions de tailles equivalentes de kaolins durs. δO18 et δD des kaolins mous et durs s’étendaient entre 18,5 à 23,1‰, et −64 à −41‰ respectivement, et ne pouvaient pas être employés pour discriminer entre les kaolins mous et les kaolins durs. Les tendances de cristallinité vs. δO18 étaient différentes pour les kaolins rassemblés à des localités différentes, et, pour un échantillon donné, δ18 diminuait généralement proportionnellement à une augmentation de cristallinité et à une augmentation de la taille de la cristallinité. Ces données indiquent que les kaolins Tertiaires ne peuvent pas être simplement dérivés des kaolins Crétacés, par ruissellement à moins que la recristallisation de l’un ou l’autre ne se soit produite. Les systématiques de δD vs. δO18 indiquent que les kaolins de Géorgie du bas Crétacé au haut Tertiaire se sont cristallisés sur une étendue de températures d’à peu près 15°C en la présence d’eaux qui ont varié peu de composition isotopique. [D.J.]

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References

  1. Austin, R. S. (1972) The origin of the kaolin and bauxite deposits of Twiggs, Wilkinson, and Washington Counties, Georgia: Ph.D. dissertation, Univ. Georgia, Athens, Georgia, 185 pp.Google Scholar
  2. Bambach, R. K. and Scotese, C. R. (1979) Paleogeographic reconstruction: the State of the Art: Short Course, Southeastern Section, Mtng., Geol. Soc. Amer., Geol. Soc. Amer., Boulder, Colorado, 58 pp.Google Scholar
  3. Brindley, G. W. (1980) Order-disorder in clay mineral structures: in Crystal Structure of Clay Minerals and their X-ray Identification, G. W. Brindley and G. Brown, eds., Monograph 5, Mineralogical Society, London, 125–195.Google Scholar
  4. Calvert, C. S. (1981) Chemistry and mineralogy of iron-substituted kaolinite in natural and synthetic systems: Ph.D. dissertation, Texas A&M Univ., College Station, Texas, 224 pp.Google Scholar
  5. Craig, H. (1961) Standard for reporting concentrations of deuterium and oxygen 18 in natural water: Science 133, 1833–1834.CrossRefGoogle Scholar
  6. Eslinger, E. V. (1971) Mineralogy and oxygen isotope ratios of hydrothermal and low-grade metamorphic argillaceous rocks: Ph.D. dissertation, Case Western Research Univ., Cleveland, Ohio, 205 pp.Google Scholar
  7. Friedman, I. (1953) Deuterium content of natural water and other substances: Geochim. Cosmochim. Acta 4, 81–103.CrossRefGoogle Scholar
  8. Godfrey, J. D. (1962) The deuterium content of hydrous minerals from the east-central Sierra Nevada and Yosemite NationalPark: Geochim. Cosmochim. Acta 26, 1215–1245.CrossRefGoogle Scholar
  9. Goldschmidt, V. M. (1926) Undersokelser over lersidimenter: Nord. Jordbrugsfors. No. 407, 434–445.Google Scholar
  10. Grim, R. E. and Wahl, F. M. (1968) The kaolin deposits of Georgia and South Carolina, USA: in Proc. 23rd Int. Geol. Cong., Prague, Symposium 1, Genesis of Kaolin Deposits (Rept. vol. 14), Prague, Academia, 9–21.Google Scholar
  11. Hassanipak, A. A. (1980) Isotopie geochemical evidence concerning the origin of Georgia kaolin deposits: Ph.D. dissertation, Georgia Inst. Tech., Atlanta, Georgia, 198 pp.Google Scholar
  12. Herbillon, A. J., Mestdagh, M. M., Vielvoye, L., and De-rouane, E. G. (1976) Iron in kaolinite with special reference to kaolinite from tropical soils: Clay Miner. 11, 201–220.Google Scholar
  13. Hinckley, D. N. (1963) Variability in “crystallinity” values among the kaolin deposits of the Coastal Plain of Georgia and South Carolina: in Clays and Clay Minerals, Proc. 11th Natl. Conf, Ottawa, Ontario, 1963, Ada Swineford, ed., Pergamon Press, New York, 229–235.Google Scholar
  14. Hinckley, D. N. (1965) Mineralogical and chemical variations in the kaolin deposits of the Coastal Plain of Georgia and South Carolina: Amer. Mineral. 50, 1865–1883.Google Scholar
  15. Hurst, V. J., Kunkle, A. C., Smith, J. M., Pickering, S. M., Shaffer, M. E., Smith, R. P., Williamson, M. E., and Moody, W. E. (1979) Field Conference on Kaolin, Bauxite, and Fuller’s Earth: Field Guide, Ann. Meet. Clay Min. Soc, Macon, Georgia, 107 pp.Google Scholar
  16. Jackson, M. L. (1956) Soil Chemical Analysis—Advanced Course: Univ. Wisconsin, Dept. of Soils, Madison, Wisconsin, 894 pp. (publ, by author).Google Scholar
  17. Kesler, T. L. (1963) Environment and origin of the Cretaceous kaolin deposits of Georgia and South Carolina: Ga. Min. Newslet. 16, 3–11.Google Scholar
  18. Komusinski, J., Stock, L., and Dubiel, S. M. (1981) Application of electron paramagnetic resonance and Mössbauer spectroscopy in the investigation of kaolinite-group minerals: Clays & Clay Minerals 29, 23–30.CrossRefGoogle Scholar
  19. Kulla, J. B. (1979) Oxygen and hydrogen isotopie fractionation factors determined in experimental clay-water systems: Ph.D. dissertation, Univ. Illinois, Urbana, Illinois, 98 pp.Google Scholar
  20. Lambe, T. W. (1953) The structure of inorganic soils: Proc. Amer. Soc. Civ. Eng. 79, 1–49.Google Scholar
  21. Lawrence, J. R. and Taylor, H. P., Jr. (1971) Deuterium and oxygen-18 correlation: clay minerals and hydroxides in quaternary soils compared to meteoric waters: Geochim. Cosmochim. Acta 35, 993–1003.CrossRefGoogle Scholar
  22. Lawrence, J. R. and Taylor, H. P., Jr. (1972) Hydrogen and oxygen isotope systematics in weathering profiles: Geochim. Cosmochim. Acta 36, 1377–1393.CrossRefGoogle Scholar
  23. Mestdagh, M. M., Vielvoye, L., and Herbillon, A. J. (1980) Iron in kaolinite: II. The relationship between kaolinite crystallinity and iron content: Clay Miner. 15, 1–13.CrossRefGoogle Scholar
  24. Murray, H. H. (1976) The Georgia sedimentary kaolins: in Proc. 7th Symp. Congress of Kaolin Inter. Geol. Correlation Program, Committee on correlation of age and genesis of kaolin, Tokyo, Japan, Univ. Tokyo (publ.), 114–125.Google Scholar
  25. Neumann, F. R. (1927) Origin of the Cretaceous white clays of South Carolina: Econ. Geol. 22, 380–386.CrossRefGoogle Scholar
  26. Plançon, A. and Tchoubar, C. (1977) Determination of structural defects in phyllosilicates by X-ray powder diffraction—I. Principle of calculation of the diffraction phenomenon: Clays & Clay Minerals 25, 436–450.CrossRefGoogle Scholar
  27. Rosenqvist, I. Th. (1959) Physicochemical properties of soils—soil-water systems: in Proc. Amer. Soc. Civil Engineers, vol. 85, Paper 2000, J. Div. Soil Mechanic and Found. No. SM 2, pt. 1, 31–53.Google Scholar
  28. Savin, S. and Epstein, S. (1970a) The oxygen and hydrogen isotope geochemistry of clay minerals: Geochim. Cosmochim. Acta 34, 25–42.CrossRefGoogle Scholar
  29. Savin, S. and Epstein, S. (1970b) The oxygen and hydrogen isotope geochemistry of ocean sediments and shales: Geochim. Cosmochim. Acta 34, 43–63.CrossRefGoogle Scholar
  30. Sayin, M. and Jackson, M. L. (1975) Anatase and rutile determination in kaolinite deposits: Clays & Clay Minerals 23, 437–443.CrossRefGoogle Scholar
  31. Sheppard, S. M. F., Nielsen, R. L., and Taylor, H. P. (1969) Oxygen and hydrogen isotope ratios of clay minerals from porphyry copper deposits: Econ. Geol. 64, 755–777.CrossRefGoogle Scholar
  32. Smith, R. W. (1929) Sedimentary kaolins of the Coastal Plain of Georgia: Ga. Geol. Surv. Bull. 44, p. 474.Google Scholar
  33. Stull, R. T. and Bole, G. A. (1926) Benefication and utilization of Georgia clays: U.S. Bur. Mines Bull. 252, 72 pp.Google Scholar
  34. Taylor, H. P., Jr. and Epstein, S. (1962) Relationship between O18/O16 ratios in coexisting minerals of igneous and metamorphic rocks. Part I. Principles and experimental results: Bull. Geol. Soc. Amer. 73, 461–480.CrossRefGoogle Scholar
  35. Veatch, O. (1909) Second report on the clay deposits of Georgia: Ga. Geol. Survey Bull. 18, 453 pp.Google Scholar

Copyright information

© The Clay Minerals Society 1985

Authors and Affiliations

  • Ali Asghar Hassanipak
    • 1
  • Eric Eslinger
    • 2
  1. 1.School of Geophysical SciencesGeorgia Institute of TechnologyAtlantaUSA
  2. 2.Department of GeologyWest Georgia CollegeCarrolltonUSA

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