MAGNETIC FABRICS OF THE TERTIARY VRONDOU PLUTONIC COMPLEX, NORTHERN GREECE.


I. Zananiri
S. Dimitriadis
D. Kondopoulou
A. Kilias
Résumé

The emplacement and tectonic evolution of the Tertiary Vrondou granitoid in the Greek Rhodope has been studied by a combination of field tectonic, microtextural and anisotropy of magnetic susceptibility (AMS) methods. The Vrondou pluton is composed of at least two intrusions, a Mid-Oligocene one at its eastern and an Early Miocene at its western parts. Room for the emplacement in both cases was provided by the opening of an extensional ramp space within a several km thick, mid-crustal subhorizontal shear zone, with a top to the SW sense, active during the Mid-Oligocene to Early Miocene period. The older eastern part of the pluton is much less deformed than the younger western part. Magmatic textures are well preserved in the older intrusion whereas they are scarcely present in the younger one. They indicate a NW-SE direction of magmatic flow in both cases. Sub-solidus plastic deformation affected mostly the younger western part of the pluton and only locally the older eastern one. In both cases mineral lineations trending NE-SW were developed. An increase in the shear rate by the Early Miocene or a localization of shear mainly in the west, in combination with the more silica saturated rock types present there, are probably the reasons for the different deformational behaviour of the two parts of the pluton.

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Références
Borradaile, G.J. & Henry, B. 1997. Tectonic applications of magnetic susceptibility and its anisotropy. Earth-Science Reviews, 42, 49-93.
Bouchez, J.-L. 1997. Granite is never isotropic: an introduction to AMS studies in granitic rocks. From: Bouchez, J.-L, Hutton, D.H.W., Stephens, W.E. (eds.), Granite: From Segregation of Melt to Emplacement Fabrics. Kluwer Academic Publishers, Dortrecht, pp. 95-112.
Bouchez, J.-L., Gleizes, G., Djouadi, T. & Rochette, P. 1990. Microstructure and magnetic susceptibility applied to emplacement kinematics of granites : the example of the Foix pluton (French Pyrenees). Tectonophysics, 184, 157-171.
Burg, J. P., Ivanov, Z., Ricou, L. E., Dimor, D. & Klain, L. 1990. Implications of shear-sense criteria for the tectonic evolution of the central Rhodope massif, southern Bulgaria. Geology, 18, 451-454.
Burg, J. P., Godfriaux, I. & Ricou, L. E. 1995. Extension of the Mesozoic Rhodope thrust units in the Vertiskos- Kerdilion Massifs (Northern Greece). C. R. Acad. Sci. Paris, 320 lia, 889-896.
Christofides, G. 1977. A contribution to the study of the plutonio rocks of Xanthi area. PhD thesis, Aristotle University of Thessaloniki.
Christofides, G., Koroneos, Α., Soldatos, T., Eleftheriadis, G. & Kilias, Α. 2001. Eocene magmatism (Sithonia and Elatia plutons) in the Internal Hellenides and implications for Eocene-Miocene geological evolution of the Rhodope Massif (Northern Greece). Acta Vulcanologica, 13 (1-2), 73-89.
Cisowski, S. 1981. Interacting vs. non-interacting single domain behavior in natural and synthetic samples. Physics of the Earth and Planetary Interiors, 26, 56-62.
Dimitriadis, S. 1995. A likely petrological evidence for large scale southwestward displacement of the Serbomacedonian over the Pangaion Unit in Late Tertiary. Geological Society of Greece, Special Publications, No 4, 21-23.
Dimitriadis, S., Kondopoulou, D. & Atzemoglou, A. 1998. Dextral rotations and tectonomagmatic evolution of the southern Rhodope and adjacent regions (Greece). Tectonophysics, 299,159-173.
Dinter, D. 1991. Neogene detachment faulting and the Rhodope metamorphic core complexes, northern Greece. EOS Trans. AGU, 72(44), Fall Meet. Suppl., 460.
Dinter, D. A. 1994. Tectonic evolution of the Rhodope metamorphic core complex, northeastern Greece. PhD thesis, 320 pp., Mass. Inst, of Technol., Cambridge.
Dinter, D. A. & Royden, L H. 1993. Late Cenozoic extension in northeastern Greece: Stryrnon Valley detachment and Rhodope metamorphic core complex. Geology, 21, 45-48.
Dinter, D., Macfarlane, Α., Harnes, W., Isachnsen, C, Bowring, S. & Royden, L. 1995. U-Pb and 4oAr/39Ar geochronology of the Symvolon granodiorite: Implications for the thermal and structural evolution of the Rhodope metamorphic core complex, northeastern Greece. Tectonics, 14,4, 886-908.
Jelinek, V. 1981. Characterization of the magnetic fabric of rocks. Tectonophysics, 79, T63-T67.
Jones, E. C, Tarney, J., Baker, J. & Gerouki, F. 1992. Tertiary granitoids of the Rhodope, northern Greece: magmatism related to extensional collapse of the Hellenic Orogen? Tectonophysics, 210, 295-314.
Kaufman, P. S. 1995. Extensional tectonic history of the Rhodope metamorphic core complex, Greece, and geophysical modeling of the Halloran Hills, California. PhD thesis, Mass. Inst, of Technol., Cambridge, 295
Kilias, A. A. & Mountrakis, D. M. 1998. Tertiary extension of the Rhodope massif associated with granite emplacement (Northern Greece). Acta Vulcanologica, 10 (2), 331-337.
Kilias, Α., Tranos, M., Orozco, M., Alonso-Chaves, F. & Soto, J. 2002. Extensional collapse of the Hellenides: a review. Rev. Soc. Geol. Espana, 15 (3-4), 129-139.
Kolokotroni, C. 1992. The emplacement and petrogenesis of the Vrodou granitoid pluton, Rhodope massif, NE Greece. PhD thesis, University of Edinburgh, 425pp.
Kolokotroni, C. N. and Dixon, J. E. 1991. The origin and emplacement of the Vrondou granite, Serres, NE Greece. Bulletin of the Geological Society of Greece, 25, 469-483.
Koukouvelas, J. & Doutsos, T. 1990. Tectonic stages along a traverse cross cutting the Rhodope zone (Greece). Geol. Rundsch. 79, 3, 753-776.
Kronberg, P. 1969. Petrografie und Tectonik im Rhodopen-Kristallin des Tsal-Dag, Simvolon und Ost-Pangaon (Griechisch-Makedonien). N. J. Geol. Pal. Abh., 7,140-156.
Kronberg, P., Meyer, W. & Pilger, A 1970. Geologie der Rila-Rhodope-Masse zwischen Strimon und Nestos (Nordgriechenland). Beih. geol. Jb. 88,133-180.
Kyriakopoulos, K.G. 1987. A geochronological, geochemical and mineralogical study of some Tertiary plutonic rocks of the Rhodope Massif and their isotopie characteristics. PhD thesis, University of Athens, 343pp.
Lowrie, W. & Fuller, M. 1971. On the alternating field demagnetization characteristics of multidomain thermoremenent magnetization in magnetite. Journal of Geophysical Research, 76, 6339-6349.
Mposkos, E. 1998. Cretaceous and Tertiary tectonometamorphic events in Rhodope zone (Greece). Penological and geochronological evidences. Bulletin of the Geological Society of Greece, vol. XXXII/3, 59-67.
Papadakis, A.N. 1965. The Serres-Drama pluton. PhD thesis, Aristotle University of Thessaloniki, 130pp.
Sklavounos, S. 1981. The Paranestion granite. Mineralogy-Petrography. PhD thesis, University of Thessaloniki, Greece, 175pp.
Soldatos, T. 1985. Petrology and geochemistry of the Elatia pluton. PhD thesis, and Scientific Annales of the Faculty of Sciences, University of Thessaloniki, Greece, 23 (37), 303pp.
Soldatos, T., Poli, G., Christofides, G, Eleftheriadis, G, Koroneos, Α. & Tommasini, S. 1998. Petrology and evolution of transitional alkaline-subalkaline granitoids from Vrondou (NE Greece): evidence for fractional crystallization and magma mixing. Acta Vulcanologica, 10 (2), 319-330.
Theodorikas, S. 1982. The mineralogy, petrology and geochemistry of the Serres-Drama granitic complex, northern Greece. PhD Thesis, University of Keele, and Scientific Annales of the Faculty of Physics-Mathematics, University of Thessaloniki, 22, no.28, Thessaloniki. 1983, 415 pp.
Trindade, R., Raposo, I., Ernesto, M. & Siqueira, R. 1999. Magnetic susceptibility and partial anhysteretic remanence anisotropies in the magnetite-bearing granite pluton of Tourao, NE Brazil. Tectonophysics, 314,443-468.
Zananiri, I., Dimitriadis, S., Kondopoulou, D. & Atzemoglou, A. 2002. A preliminary AMS study in some Tertiary granitoids from Northern Greece: integration of tectonic and paleomagnetic data. Physics and Chemistry of the Earth, 27, 25-31, 1289-1297.
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