Clays and Clay Minerals

, Volume 42, Issue 5, pp 582–592 | Cite as

Palagonite Reconsidered: Paracrystalline Illite-Smectites From Regoliths on Basic Pyroclastics

  • Vadim Berkgaut
  • Arieh Singer
  • Karl Stahr


Poorly crystalline authigenic alteration products of basic pyroclastics from the Golan Heights, Israel, were investigated by XRD, DTA, TGA, FTIR and chemical analysis. Modeling XRD patterns with the use of NEWMOD code provided a way to identify these clays as random interstratified illite/smectites (I/S) with ∼70% of illitic interlayers. Their characteristic features were very poor basal reflections, distinct hk bands, high CEC and low (∼2%) K2O content. Crystallite thickness distribution was found to follow Ergun’s model with a weight-average thickness of 2.7–2.8 layers. A new method was proposed to calculate the proportion of kaolinite and 2:1 minerals in their mixtures and the average crystallochemical formula of 2:1 minerals in the presence of kaolinite. The method starts from data of chemical analysis and TGA and assumes that the anionic frameworks of kaolinite and 2:1 minerals are exactly O10(OH)8 and O10(OH)2 respectively. The number of OH-groups per ten oxygens not bonded to H in the empirical formula of the mixture is used to evaluate the proportion of kaolinite. Formation of I/S in well-drained environments under humid mediterranean climatic conditions was attributed to long dry seasons. Interstitial water composition was shown to be consistent with authigenic formation of I/S.

Key Words

Basic pyroclastics Humid mediterranean weathering llite/smectite Poorly-ordered layer silicates 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Bain, D. C., and B. F. L. Smith. 1987. Chemical analysis. In A Handbook of Determinative Methods in Clay Mineralogy. M. J. Wilson, ed. Glasgow and London: Blackie, New York: Chapman and Hall, 248–274.Google Scholar
  2. Brigatti, M. F. 1983. Relationships between composition and structure in Fe-rich smectites. Clay Miner.. 18. 177–186.CrossRefGoogle Scholar
  3. Dan, J., and A. Singer. 1973. Soil evolution on basalt and basic pyroclastic materials in the Golan Heights. Geoderma 9: 165–192.CrossRefGoogle Scholar
  4. Drits, V. A., and A. G. Kossovskaya. 1990. Clay Minerals: Smectites and Interstratified Mica-Smectites and Chlorite-Smectites. Moscow: “Nauka,”. 24. pp. [in Russian].Google Scholar
  5. Ergun, S. 1970. X-ray scattering by very defective lattices. Phys. Rev. B1: 3371.CrossRefGoogle Scholar
  6. Fanning, D. S., V. Z. Keramidas, and M. A. El-Desoky. 1989. Micas. In Minerals in Soil Environments, 2nd ed. J. B. Dixon and S. B. Weed, eds. Madison: SSSA, 551–634.Google Scholar
  7. Farmer, V. C., W. J. McHardy, F. Palmieri, A. Violante, and P. Violante. 1991a. Synthetic allophanes formed in calcareous environments. Nature, conditions of formation and transformations. Soil Sci. Soc. Amer. J. 55: 1162–1166.CrossRefGoogle Scholar
  8. Farmer, V. G, G. S. R. Krishnamurti, and P. M. Huang. 1991b. Synthetic allophane and layer-silicate formation in SiO2-Al2O3-FeO-Fe2O3-MgO-H2O systems at 23°C and 89°C in a calcareous environment. Clays & Clay Miner.. 39. 561–570.CrossRefGoogle Scholar
  9. Garrels, R. M. 1984. Montmorillonite/illite stability diagrams. Clays & Clay Miner. 32: 161–166.CrossRefGoogle Scholar
  10. Gislason, S. R., and H. P. Eugster. 1987. Meteoric water-basalt interaction. I: A laboratory study. Geochim. Cosmochim. Acta. 51. No. 10. 2827–2840.CrossRefGoogle Scholar
  11. Hashimoto, I., and M. L. Jackson. 1960. Rapid dissolution of allophane and kaolinite-halloysite after dehydration. Clays & Clay Miner. 7: 102–113.CrossRefGoogle Scholar
  12. Jahn, R., M. Zasei, and K. Stahr. 1987. Formation of clay minerals in soils developed from basic volcanic rocks under semi-arid climatic conditions in Lanzarote, Spain. Catena 14: 359–368.CrossRefGoogle Scholar
  13. Jackson, M. L. 1974. Soil Chemical Analysis—Advanced Course, 2nd ed. Madison: Published by the author. 89. pp.Google Scholar
  14. Kawano, M., and K. Tornita. 1992. Formation of allophane and beidellite during hydrothermal alteration of volcanic glass below 200°C. Clays & Clay Miner. 40: 666–674.CrossRefGoogle Scholar
  15. Klug, H. P., and L. E. Alexander. 1974. X-ray Diffraction Procedures for Polycrystalline and Amorphous Materials. Wiley, New York. 66. pp.Google Scholar
  16. Mehra, O. P., and M. L. Jackson. 1960. Iron oxide removal from soils and clays by a dithionite-citrate system buffered with sodium bicarbonate. Clays & Clay Miner. 1: 317–327.Google Scholar
  17. Mizota, C. 1987. Chemical and mineralogical characterization of soils derived from volcanic ashes. In Agriculture and Soils in Kenya. A Case Study of Farming Systems in the Embu District and Characterization ofVolcanogenous Soils. S. Hirose, ed. Tokyo: College of Agric. and Veter. Medicine, Nihon Univ., 110–123 [in Japanese].Google Scholar
  18. Mizota, C., and J. Chapelle. 1988. Characterization of some Andepts and Andic soils in Rwanda, Central Africa. Geoderma 43: 131–141.CrossRefGoogle Scholar
  19. Mizota, C., I. Kawasaki, and T. Wakatsuki. 1988. Clay mineralogy and chemistry of seven pedons formed on volcanic ash, Tanzania. Geoderma 43: 131–141.CrossRefGoogle Scholar
  20. Mizota, C., and L. P. Reeuwijk. 1989. Clay Mineralogy and Chemistry of Soils Formed in Volcanic Material in Diverse Climate Regions. Soil Monograp. 2. ISRIC, Wageningen, Holland.Google Scholar
  21. Moore, D. M., and R. C. Reynolds Jr. 1989. X-Ray Diffraction and Identification and Analysis of Clay Minerals. Oxford, New York: Oxford Univ. Press. 33. pp.Google Scholar
  22. Nadeau, P. H., J. M. Tait, W. J. McHardy, and M. J. Wilson. 1984. Interstratified XRD characteristics of physical mixtures of elementary clay particles. Clay Miner.. 19. 67–76.CrossRefGoogle Scholar
  23. Pevear, D. R. 1989. Introduction. In CMS Workshop Lectures, Vol. 1. Quantitative Mineral Analysis of Clays. D. R. Pevear and F. A. Mumpton, eds. Evergreen, Colorado: The Clay Minerals Society, 1–2.Google Scholar
  24. Polemio, M., and J. D. Rhoades. 1977. Determining cation exchange capacity. A new procedure for calcareous and gypsiferous soils. Soil Sci. Soc. Amer. J. 41: 524–528.CrossRefGoogle Scholar
  25. Quantin, P., D. Badaut-Trauth, and F. Weber. 1975. Mise en evidence de minéraux secondaires, argiles et hydroxides, dans les andosols des Nouvelles-Hébrides, après la defer-rification par la méthode de Endredy. Bull. Groupe franc. Argiles 27: 51–67.CrossRefGoogle Scholar
  26. Reynolds, R. C. 1980. Interstratified clay minerals. In Crystal Structures of Clay Minerals and Their X-ray Identification. G. W. Brindley and G. Brown, eds. London: Mineralogical Society, 249–304.Google Scholar
  27. Singer, A. 1974. Mineralogy of palagonitic material from the Golan Heights, Israel. Clays & Clay Miner. 22: 231–240.CrossRefGoogle Scholar
  28. Singer, A., and J. Navrot. 1977. Clay formation from basic volcanic rocks in a humid Mediterranean climate. Soil Sci. Soc. Amer. J.. 41. No. 3. 645–650.CrossRefGoogle Scholar
  29. Singer, A., A. Silber, and D. Szafranek. 1991. Nodular silica-phosphate minerals of the Har Peres pyroclastics, Golan Heights. N. Jb. Miner. Mh. Jg. H.8: 337–354.Google Scholar
  30. Singer, A., and A. Banin. 1990. Characteristics and mode of formation of palagonite—A review. In Proc. 9th Int. Clay Confi, Strasbourg, 1989. V. C. Farmer and Y. Tardy, eds. Sci. Gwol, Mwm. 88: 173–181.Google Scholar
  31. Srodon, J., and D. D. Eberl. 1984. Illites. In Micas. S. W. Bailey, ed. Chelsea, Michigan: Mineralogical Soc. of America, 495–544.CrossRefGoogle Scholar
  32. Van der Gaast, S. J., C. Mizota, and J. H. F. Jansen. 1986. Curved smectite in soils from volcanic ash in Kenya and Tanzania. A low angle X-ray powder diffraction study. Clays & Clay Miner. 34: 665–671.CrossRefGoogle Scholar
  33. Wada, K. 1987. Minerals formed and mineral formation from volcanic ash by weathering. Chem. Geol. 60: 17–28.CrossRefGoogle Scholar
  34. Wada, K., Y. Kakuto, and H. Ikawa. 1990. Clay minerals of two Eutrandepts of Hawaii, having isohyperthermic temperature and ustic moisture regimes. Soil Sci. Soc. Amer. J. 54: 1173–1178.CrossRefGoogle Scholar
  35. Wada, K. 1980. Mineralogical characteristics of Andisols. In Soils and Variable Charge. B. K. G. Theng, ed. Lower Hutt, New Zealand: Soil Bureau, 87–109.Google Scholar
  36. Weller, U. 1992. Bodenentwicklung und Tonmineralbildung aus vulkanischem Tuff auf den Golanhöhen. Israel: Diplomarbeit, Universität Hohenheim. 6. pp.Google Scholar
  37. White, L. P. 1967. Ash soils in Western Sudan. J. Soil Sci.. 18. No. 2. 309–317.CrossRefGoogle Scholar

Copyright information

© The Clay Minerals Society 1994

Authors and Affiliations

  • Vadim Berkgaut
    • 1
  • Arieh Singer
    • 1
  • Karl Stahr
    • 2
  1. 1.The Seagram Centre for Soil and Water SciencesFaculty of AgricultureRehovotIsrael
  2. 2.Institut für BodenkundeUniversität HohenheimStuttgartGermany

Personalised recommendations