ON THE RELATIVELY COMPOSITIONAL HOMOGENEITY OF ALBANIAN EASTERN OPHIOLITIC BELT

PDF (English)
Δημοσιευμένα: Ιουλ 28, 2016
DOI: https://doi.org/10.12681/bgsg.14106
Α. Çina
Institute of Geosciences, Energy, Water and Environment, Polytechnic University of Tirana
Περίληψη

Ophiolitic formation of Albanides, named as Mirdita zone, represents a compact
segment of oceanic lithosphere of Middle-Upper Jurassic. Based on petrographic,
geochemical and metalogenical features two types of belts are distinguished: western
MORB and eastern SSZ types. In fact, structural and geological units as well as many
other elements have shed light on lack of a sharp separation between the two belts.
Recent investigations have evidenced that different ultramafic massifs of western
ophiolitic formation, represent an evident variation of their composition from
harzburgite to lherzolitic -types. This composition reflects a different grade of partial
melting of upper mantle. Peridotites show a high variability, from 0.3 - 3.8 wt.%
Al2O3, varying from small to highly extreme depleted peridotite.
On the contrary, Albanian eastern belt, it seems to be formed by a more homogeneous
hartzburgitic mantle.
Detailed petrologic and metallogenic investigations have evidenced that this belt
changes also from one massif to another, naturally at a smaller level, therefore it is
easier to be named relatively homogeneous. It is distinguished by a higher melting
degree, chiefly of hartzburgitic-type, characterized by whole and thick ultramafic
section, as well as by metalogenic variety, mostly of metallurgic-type of chromite
mineralization. It is supposed that rock-forming and mineraluzation processes have
been developed not uniformly along the ophiolitic belt.

Λεπτομέρειες άρθρου
  • Ενότητα
  • Πετρολογία και Ορυκτολογία
Creative Commons License

Αυτή η εργασία είναι αδειοδοτημένη υπό το CC Αναφορά Δημιουργού – Μη Εμπορική Χρήση 4.0.

Οι συγγραφείς θα πρέπει να είναι σύμφωνοι με τα παρακάτω: Οι συγγραφείς των άρθρων που δημοσιεύονται στο περιοδικό διατηρούν τα δικαιώματα πνευματικής ιδιοκτησίας επί των άρθρων τους, δίνοντας στο περιοδικό το δικαίωμα της πρώτης δημοσίευσης. Άρθρα που δημοσιεύονται στο περιοδικό διατίθενται με άδεια Creative Commons 4.0 Non Commercial και σύμφωνα με την οποία μπορούν να χρησιμοποιούνται ελεύθερα, με αναφορά στο/στη συγγραφέα και στην πρώτη δημοσίευση για μη κερδοσκοπικούς σκοπούς. Οι συγγραφείς μπορούν να: Μοιραστούν — αντιγράψουν και αναδιανέμουν το υλικό με κάθε μέσο και τρόπο, Προσαρμόσουν — αναμείξουν, τροποποιήσουν και δημιουργήσουν πάνω στο υλικό.

Λήψεις
Τα δεδομένα λήψης δεν είναι ακόμη διαθέσιμα.
Αναφορές
Alliu I., Beccaluva L., Çina A., Coltorti M., Dobi A., Gjata K., Gjoni V., Halku A., Kodra A.,Premti I., Saccani E., Shallo M., Siena F., Stermasi Sh. and Tashko A., 1994. The Skanderbeg and Bulqiza mafic-ultramafic ophiolitic complexes and their relationship with chromititic ore deposits, Ofioliti, 19(1), 27-55.
Bebien I. and Shallo M., 1995. Intrusive ultramafic rocks in Albania ophiolites, EUG. 8, Strasbourg(abstract volume).
Beccaluva L., Ohnenstetter D., Ohnenstetter M. and Paupy A., 1984.Two magmatic series with island-arc affinity within the Vourinos ophiolite, Contribution to Mineralogy and Petrology,85, 253-271.
Beccaluva L., Coltorti M., Saccani E., Siena F. and Zeda O., 1994. Midocean ridge and suprasubduction affinities in the ophiolite belts of Albania, Ofioliti, 19(1), 77-97.
Beqiraj A., Masi U. and Violo M., 2001. Geochemical characterization of podiformchromite ores from the Bulqiza ultramafic massif and hits for prospection, Journal of Exploration and Maining Geology, 9(2), 268-276.
Chiari A., Marcucci M. and Prela M., 2004. Radiolarian assemblages from the Jurassic charts of Albania: new data, Ofioliti, 29(2), 95-105.
Çina A., Casli H. and Goci L., 1986. Chromites in the ophiolites ofAlbanides. In: “Chromites”,UNESCO)’s IGCP 197 project, Metallogeny of Ophiolites, Theophrastus Publ., Athens, 107-126.
Çina A., 2010. Mineralogy of chromitite, Bulqiza ultramafic massif, Albanian ophiolitic complex,12th International Congress of the Geological Society of Greece, Patras, XLlII/5, 2577-2587.
Çina A., 2010. Pentlandite mineralization related to Albanian ophiolites, XIX Congress of the Carpathian-Balkan Geological Association, Greece, 110, 317-323.
Çina A. and Meshi, A., 2013. Later chromitites from ophiolites of Albania. In: Basalt 2013, Cenozoic Magmatism in Central Europe, 43-44.
Dick H.J. and Bullen T., 1984. Chromian spinel as a petrogenetic indicator in abyssal and Alpinetype peridotite and specially associated lavas, Contribution to Mineralogy and Petrography,86, 54-76.
Economou M., 1983. Platinum group metals in chromite ores from the Vourinos ophiolite complex,Greece, Ofioliti, 8(3), 339-356.
Economou M., Dimou E., Economou G., Migiros G., Vacondios I., Grivas E., Rassios A. and Dabitzias, S., 1986. Chromite deposits of Greece. In: “Chromites”, UNESCO’s IGCP 197project, Metallogeny of ophiolites, Theofrastus publication, Athens, 129-159.
Economou-Eliopoulos M. and Vacandios I., 1995. Geochemistry of chromitites and host rocks from the Pindos ophiolite complex, northwestern Greece, Chemical Geology, 122, 99-108.
Hoeck V., Koller F., Meisel T., Onuzi K. and Kneringer E., 2002. The Jurassic South Albanian Ophiolites: MOR-vs SSZ-type ophiolites, Lithos, 65, 143-164.1798
Kapsiotis A., Tsikouras B., Grammatikopoulos T., Karipi S. and Hatzipanagiotou K., 2007. On the metamorphic modification of Cr-spinel compositions from the ultrabasic rocks of the Pindos ophiolite complex (NW Greece), Bulletin of the Geological Society of Greece,
Procedings of the 11th International Congress, XXXX, 781-793.
Karaj N., 1992. Repartition des platinoides des chromites et sulfures dans le massif de Bulqiza, Albanie. Incidence sur les proccesus métallogeniques dans les ophiolites, Thèse, Univ.d’Orléèans, 400 pp.
Kodra A., Gjata K. and Bakalli F., 1995. The Mirdita oceanic basin from rifting to the closure. In:Workshop on Albanian ophiolites and related mineralizations, Documents du BRGM 244,Edition BRGM, France, 9-26.
Koller F., Hoeck V., Ionescu C. and Onuzi K., 2009. Contrasting mantle section in Albanian ophiolites: evidences from mineral and bulk rock composition. In; MinPet 2009 and 4th Mineral sciences in the Carpathians Conference, Budapest, Band, 155, 84.
Konstantopoulou G. and Economou-Eliopoulos M., 1990. Geochemistry of the Vourinos chromite ores, Greece. In: Ophiolites, Oceanic crustal Analogues, Symposium “Trodoos 1987”,Nicosia, Cyprus, 605-613.
Manika K., 1994. Pétrologie du massif ophiolitique de Shebenik, Albanie, Thèse, Univ. de Paris-Sud, 297 pp.
Meshi A., Hoxha I. and Milushi I., 2005. Chromitites in Mirdita ophiolite (Albania); Structure and genetic implications, Journal of Alpine geology, 49, 1-29.
Neziraj A., 1992. Etude pétrologique et métallogenique du massif ophiolitique de Tropoja, Albanie. Reference particuliere aux gisements de chromite et éléments du group du platine, Thèse,Univ. d’Orléans, France, 544 pp.
Nicolas A., Boudier F. and Meshi A., 1999. A slow spreading accretionin the ophiolite of Mirdita(Albania), Journal of Geophysical Researcher, 104(87), 15155-15167.
Ohnenstetter M., Karaj N., Neziraj A., Johan Z. and Çina A., 1991. Le potential platinifere des ophiolites: minéralisations en éléments du group du platine (PGE) dans les massifs de Tropoja et Bulqiza, Albanie, C.R. Acad. Sci. Fr., 313(II), 201-208.
Rassios A. and Kostopoulos D., 1990.The geochemistry of dunite and its relation to the position of chromitites in the Vourinos, Ophiolite complex, Greece, In: Ophiolites, Oceanic Crustal Analogues, Symp. “Trodoos 1987”, Nicosia, Cyprus, 593-603.
Shallo M., Çina A. and Turku I., 1995.Outline of the metallogeny of the Albanian MOR and SSZtype ophiolites. In: Workshop on Albanian ophiolites and related mineralizations,Documents du BRGM244, editions of BRGM, France, 27-46.
Tashko A. and Gjata K., 1990. Rreth gjeokronologjise absolute te masiveve ultrabasike te Albanideve, Bul. Shkenc. Gjeol., 1, 39-50.