Kaolinization processes in the phyolitic rocks of Kefalos, Kos island, Aegean Sea, Greece

PDF
Published: Jan 1, 2001
DOI: https://doi.org/10.12681/bgsg.17101
Keywords:
Kos Island kaolinite hydrothermal activity dickite mixed-layer kaolinite-smectite rhyolite
D. PAPOULIS
Department of Geology University of Patras, Section of earth materials
P. TSOLIS - KATAGAS
Department of Geology University of Patras, Section of earth materials
Abstract

Kaolin occurrences in the South Kefalos peninsula, Kos island, Aegean sea, Greece, are products of hydrothermal alteration of rocks of rhyolitic composition. The chemical, mineralogical and textural characteristics of kaolin occurrences were investigated by X-Ray diffraction (XRD), Analytical scanning electron microscopy (SEM) and bulk rock chemical analyses. Attempts have been made to correlate the primary with secondary mineral assemblages and to establish the factors controlling the stepwise character of the transition from the fresh rhyolitic to kaolinized rocks. The kaolinization processes follows two main alteration pathways: I) Kfeldspar —» Mixed-layer kaolinite-smectite —» kaolinite —> dickite. II) Na-plagioclase —> kaolinite —> dickite

Article Details
  • Section
  • Mineralogy and Crystallography
Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

Authors who publish with this journal agree to the following terms:

Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution Non-Commercial License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.

Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g. post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal. Authors are permitted and encouraged to post their work online (preferably in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work.

Downloads
Download data is not yet available.
References
BOVEN, Α., BROUSSE, R., DALABAKIS, P. ET PASTEELS, P. (1987). Geological and geo-chronological evidences on the evolution of KOS-JALI-NISYROS eruptive centres, Aegean arc, Greece. Terra Cognita ,7, 328-329.
CASES, J.M., LIÉTARD, O., YVON, J. ET DELON, J.F. (1982). Etudes des propertiétés cristallochimiques, morphologiques, superficielles de kaolinites désordonnées. Bull. Minéral.,105, 439-455.
DALABAKIS, P. (1987). La volcanisme recent de Γ île de Kos. Thèse de doctorat, Paris xi, 266p.
DANDO, PR., STUBEN, D. AND VARNAVAS, S.P (1999). Hydrothermal!sm in the Mediterranean Sea. Progress in Oceanography, 333-367.
GUINIER, A. (1956). Théorie et Technique de la Radiocristallographie, pp. 462-465. Dunod Ed.,Paris.
HINCKLEY, D.N. (1963). Variability in crystallinity values among the kaolin deposits of the coastal plain of Georgia and South Carolina. Clays Clay Miner. 11, 229-235.
INOUE, A (1995). Formation of Clay Minerals in Hydrothermal Environments. In: Velde, B. (ed) Origin and Mineralogy of Clays. Springer-Verlag. Berlin, pp 268-329.
KELEPERTSIS, A.E. AND REEVES, R.R. (1987). The geochemistry of the volcan rocks of Kos island, Aegean sea, Greece. Ann.Geol. Des Pays Hell., 33, 2, 443-461.
KELLER, W.D. (1976). Scan electron micrographs of kaolins collected from diverse environments of origin-I. Clays and Clay Minerals 24, 107-113.
LIETARD, O. (1977). Contribution a Γ étude des propriétés physicochimiques, crystallographiques et morphologiques des kaolins. Thèse Doc. Sci. Phys. Nancy, France.
NEWMAN, A.C.D. (1987). Chemistry of clays and clay minerals. John Wiley & sons. New York, 480p.
PARASKEVOPOULOS, G (1960). The perlites of the Kefalos peninsula of Kos Island. Ann.Geol. Des Pays Hell.,v. XI. 125-136.
THORPE, S.D. (1982). Andésites: Orogenic Andésites and Related Rocks. John Wiley & sons. Norwich, 724p.
TSOLIS-KATAGAS, P. AND MAVRONICHI, M. (1989). Kaolinization of the Kimolos island volcanics, Cyclades, Greece. Clay Minerals, 24, 75-89.
TRIANTAPHYLLIS, M. (1994). Geological map of Greece. Western Kos sheet (Kefalos) 1:50.000. IGME, Athens.
VARNAVAS, S.P. AND CRONAN, D.S. (1991). Hydrothermal metallogenic processes off the islands of Nisiros and Kos in the Hellenic Volcanic Arc. Marine Geology, 99, 109-133.
Most read articles by the same author(s)