STUDY OF THE METAMORPHIC EVOLUTION OF A CARBONATE-BEARING METAPERIDOTITE FROM THE SIDIRONERO COMPLEX (CENTRAL RHODOPE, GREECE) USING P-T AND P(T)-XCO2 PSEUDOSECTIONS


E. Mposkos
I. Baziotis
Résumé

The carbonate-bearing metaperidotite from Sidironero Complex, north of the Xanthi town is composed primarily of olivine and orthopyroxene megacrysts and of Ti-clinohumite, tremolite, chlorite, dolomite, magnesite, talc, antigorite and spinel group minerals. The metaperidotite underwent a prograde HP metamorphism probably isofacial with the neighboring amphibolitized eclogites. Calculated P-T and P(T)-XCO2 phase diagram sections (pseudosections) for the bulk rock composition showed that XCO2 in the fluid phase was extremely low (≤0.008) at the first stages of the metamorphism and increased up to 0.022 at the peak P-T conditions ~1.5 GPa and 690 0C. The prograde metamorphism probably started from a hydrated and carbonated assemblage including talc+chlorite+magnesite+dolomite and proceeded with tremolite and antigorite formation before olivine growth, and orthopyroxene formation after olivine growth (Ol-1). Matrix dolomite, breakdown of chlorite (Chl-1) to Cr spinel+olivine and of Ti-clinohumite to olivine+Mg-ilmenite occurred during decompression. The P-T path is constrained by the absence of clinopyroxene in the metaperidotite.

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  • Petrology and Mineralogy
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Références
Bauer, C., Rubatto, D., Krenn, K., Proyer, A. and Hoinkes, G. 2007. A zircon study from the Rhodope
metamorphic complex, N-Greece: Time record of a multistage evolution. Lithos, 99, 207-228.
Bosse, V., Boulvais, P., Gautier, P., Tiepolo, M., Ruffet, G., Devidal, J.L., Cherneva, Z., Gerdjikov,
I. and Paquette, J.L., 2009. Fluid-induced disturbance of the monazite Th–Pb chronometer: In
situ dating and element mapping in pegmatites from the Rhodope (Greece, Bulgaria). Chemical
geology 261, 3-4, 286-302.
Connolly, J. A. D. 2009. The geodynamic equation of state: what and how. Geochemistry, Geophysics,
Geosystems, 10, QXXXX. DOI: 10.1029/ 2009GC002540.
Evans, B.W. and Frost, B.R. 1975. Chrome-spinel in progressive metamorphism-a preliminary analysis.
Geochimica et Cosmochimiica Acta, 39, 959-972.
Holland, T., Baker, J. and Powell, R. 1998. Mixing properties and activity-composition relationships
of chlorites in the system MgO-FeO-Al2O3-SiO2-H2O. European Journal of Mineralogy,
, 395–406.
Holland, T. J. B. H. and Powell, R. 1996. Thermodynamics of order-disorder in minerals.2. Symmetric
formalism applied to solid solutions. American Mineralogist, 81, 1425-1437.
Holland, T. J. B. H. and Powell, R. 1998. An internally consistent thermodynamic data set for phases
of petrological interest. Journal of Metamorphic Geology, 16, 309–343.
Kassoli-Fournaraki, A., Filippidis, A., Kolcheva, K., Hatzipanayotou, K., Koepke, J. and Dimadis,
E. 1995. Multi-stage alteration of the Gorgona ultramafic body, Central Rhodope Massif, Greece.
Chemie der Erde, 55, 331-340.
Krohe, A. & Mposkos, E. 2002. Multiple generations of extensional detachments in the Rhodope
Mountains (N.Greece): evidence of episodic exhumation of high-P rocks. In: Blundell, D.J.,
XLIII, No 5 – 2678
Neubauer, G. and Von Quant, A. (eds.): The timing and location of major ore deposits in an
evolving orogen. Geological Society of London, Special Publication, 204, 151-178.
Liati, 2005. Identification of repeated Alpine (ultra) high-pressure metamorphic events by U–pb
SHRIMP geochronology and REE geochemistry of zircon: the Rhodope zone of Northern
Greece, Contributions to Mineralogy and Petrology, 150, 608–630.
Liati, A. and Mposkos, E. 1990. Evolution of the eclogites in the Rhodope Zone of northern Greece,
Lithos, 25, 89–99.
Lips, A.L.W., White, S.H. and Wijbrans, J.R. 2000. Middle–Late Alpine thermotectonic evolution
of the southern Rhodope Massif, Greece. Geodinamica Acta, 13, 281–292.
Martin, R.F. 1998. Symbols of the rock-forming minerals. The Nomenclature of minerals: A compilation
of IMA reports. IMA`98 Toronto, 148-149.
Mposkos, E. and Kostopoulos, D. 2001. Diamond, former coesite and supersilicic garnet in metasedimentary
rocks from the Greek Rhodope: a new ultrahigh-pressure metamorphic province established.
Earth and Planetary Science Letters, 192, 497-506.
Mposkos, E. and Krohe, A. 2000. Petrological and structural evolution of continental high pressure
(HP) metamorphic rocks in the Alpine Rhodope domain (N.Greece). Proceedings of the 3rd International
Conference on the Geology of the Eastern Mediterranean, 221-232.
Mposkos, E. and Krohe, A. 2006. P-T-deformation paths of closely associated UHP (diamond-bearing)
crustal and mantle rocks of the Kimi Complex: Implications for the tectonic history of the
Rhodope Mountains, northern Greece. Canadian Journal of Earth Sciences, 43, 1755-1776.
Perraki, M., Proyer, A., Mposkos, E., Kaindl, R., Baziotis, I. and Hoinkes, G. 2004. Micro- and nanodiamonds
in garnets of metapelitic rocks from the Greek Rhodope : an in situ micro-Raman
study. Proceedings of the 5th International Symposium for Eastern Mediterranean Geology,
-1219.
Perraki, M., Proyer, A., Mposkos, E., Kaindl, R. and Hoinkes, G. 2006. Raman micro-spectroscopy
on diamond, graphite and other carbon polymorphs from the ultrahigh-pressure metamorphic
Kimi Complex of the Rhodope Metamorphic Province, NE Greece. Earth and Planetary Science
Letters, 241, 672-685.
Von Huene, R., Ranero, C.R. and Vannucchi, P. 2004. Generic model of subduction erosion. Geology,
, 913-916.
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