NEW EVIDENCES OF THE LOW-P/HIGH-T PRE-ALPINE METAMORPHISM AND MEDIUM-P ALPINE OVERPRINT OF THE PELAGONIAN ZONE DOCUMENTED IN METAPELITES AND ORTHOGNEISSES FROM THE VORAS MASSIF, MACEDONIA, NORTHERN GREECE

PDF (English)
Publiée : Jan 1, 2004
DOI : https://doi.org/10.12681/bgsg.16753
E. Mposkos
department of Geological Sciences, School of Mining and Metallurgical Engineering, National Technical University of Athens
A. Krone
University of Muenster, Institute for Mineralogy, Laboratory for Geochronology
Résumé

Pelitic rocks of the pre-Alpine "gneiss series" from the Voras Massif record a polymetamorphic history of three metamorphic events; a first HT event indicated by migmatitization phenomena, a subsequent LP-HT event (andalusite-sillimanite series) at 2.5-3 Kbar and 610-640°C, and a third medium-P event at ~11 Kbar and ~550°C. The LP-HT metamorphism is associated with intrusion of Variscan granitoid plutois in a magmatic arc setting. The medium-P metamorphism records an Alpine event (probably Early Cretaceous) indicated by kyanite, chlohtoid, garnet and staurolite formation replacing andalusite and cordierite. The Variscan granitoids and the overlying lithologies of the "schist series" are affected only by the medium-P metamorphism. Granitoids are transformed into phengite orthogneisses having the mineral assemblage phen (Si=3.35-3.47 a.p.f.u.)±Bt-Ab-Kfs- Qtz±Czo±Grt and high-alumina pelites into gamet-chloritoid schists with the mineral assemblage Grt-Ctd-Chl-Ms-Qtz-Rt±llm. The "schist series" which underlies the Late Triassic-Early Jurassic marbles and overlies lithologies of the "gneiss series" and metagranitoids represents protoliths of the Permo-Triassic volcanosedimentary series deposited at the eastern margin of the Pelagonian continental block

Article Details
  • Rubrique
  • Petrology
Creative Commons License

Ce travail est disponible sous licence Creative Commons Attribution - Pas d’Utilisation Commerciale 4.0 International.

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.

Téléchargements
Les données relatives au téléchargement ne sont pas encore disponibles.
Références
Avgerinas, Α., Kilias, Α., Koroneos, Α., Mountrakis, D., Frisch, W. and Dunkl, I., 2001: Cretaceous structural evolution of the Pelagonian crystalline in western Voras Mt. (Macedonia, Northern Greece). Bull.Geol.Soc. Greece. XXXIV/1, 129-136.
Barton, CM., 1976: The tectonic vector and emplacement age of an allochthonous basement slice in the Olympos area, N.E. Greece. Bull.Soc.Geol. France, 18, 253-258.
Berman, R.G., 1991: Thermobarometry using multiequilibrium calculations: a new technique with petrologie applications. Canadian Mineralogist, 29, 833-855.
Bucher, K.N., and Frey, M., 1994: Petrogenesis of metamorphic rocks. Springer Verlag, Berlin. 318 pp.
Katerinopoulos, Α., Kyriakopoulos, K., Del Moro, Α., Mitropoulos, P., and Giannoti, U., 1992: Comparative study of Hercynian granitoids from NW Greece and S. Yugoslavia. Chem. Erde, 52, 261-276.
Kilias, Α., and Mountrakis, D., 1989: The Pelagonian nappe. Tectonics, metamorphism and magmatism. Bull.Geol.Soc. Greece, 23/1, 29-46 (in Greek with English abstract).
Massonne, H. - J., and Schreyer, W., 1987: Phengite geobarometry based on the limiting assemblage with Kfeldspar, phlogopite, and quartz. Contrib. Mineral. Petrol., 96, 212-224.
Mountrakis, D., Sapountzis, E., Kilias, Α., Elefteriadis, G. and Christofidis, G., 1983: Paleogeographic conditions in the western Pelagonian margin in Greece during the initial rifting of the continental area. Can. J. Earth Sci., 20, 1673-1681.
Mountrakis, D., 1983: The geological structure of the northern pelagonian zone and the geotectonic evolution of the internal Hellenides. Habilit. Thesis. Univ. Thessaloniki, 289 p. (in Greek with English summary).
Most, T., Frisch, W., Dunkl, I., Kadosa, B., Boev, B., Avgerinas, A. and Kilias, Α., 2001: Geochronological and structural investigations of the northern Pelagonian crystalline zone. Constraints from K-Ar and zircon and apatite fission track dating. Bull.Geol.Soc. Greece. VXXXIV/1, 91-95.
Mposkos, E., and Perraki, M., 2001 : High pressure Alpine metamorphism of the pelagonian allochton in the Kastania area (southern Vermion), Greece. Bull. Geol. Soc. Greece V XXXIV/3, 939-947.
Mposkos, E., Kostopoulos, D. and Krohe, Α., 2001: Low-P/High-T pre-Alpine metamorphism and medium-P Alpine overprint of the Pelagonian zone documented in high-alumina metapelites from the Vernon Massif, Western Macedonia, Northern Greece. Bul.Geol.Soc. Greece V. XXXIV/3, 949-958.
Mposkos, E., Krohe, A. and Perraki, M., 2003: Record of Variscan Low-P/High-T metamorphism in Alpine medium-P rocks of the Pelagonian zone. Greece. EGS-AGU-EUG Joint Assembly. Nice, France. Abstract.
Reischmann, T., Kostopoulos, D., Loos, S., Anders, B., Avgerinas, A. and Sklavounos, S., 2001: Late Palaeozoic magmatism in the basement rocks southwest of Mt. Olympos, central Pelagonian zone, Greece: Remnants of a Permo-Carboniferous magmatic arc. Bull.Geol.Soc. Greece. XXXIV/3, 985-993.
Yarwood, G.A. & Aftalion, M., 1976: Field relations and U-Pb geochronology of a granite from the Pelagonian Zone of the Hellenides (High Pieria, Greece). Bull Soc. Geol. DE France ., 18, 259-264.
Yarwood, G.A. & Dixon, J.E., 1977: Lower Cretaceous and younger thrusting in the Pelagonian rocks of High Pieria, Greece. Colloq. Aegean Region, Athens, 6th, 1, 269-280.
Articles les plus lus par le même auteur ou la même autrice