PETROLOGY, GEOCHEMISTRY AND GEOTECTONIC SETTING OF THE TITAROS OPHIOLITE AND ASSOCIATED PELAGONIAN BASEMENT ROCKS IN THE AREA NW OF MT. OLYMPOS, GREECE


Published: Jan 1, 2007
Keywords:
Wehrlite rodingite tawmawite Raman supra-subduction zone
D. Boudi
E. Prophitis
P. Zachariadis
D. Kostopoulos
E. Baltatzis
E. Chatzitheodoridis
Abstract

The Titaros ophiolite in Greece is a coherent thrust sheet of oceanic rocL· that lies atop Permo-Carboniferous granitic orthogneisses and amphibolites of unknown age of the eastern Pelagonian margin in the area NW of Mt. Olympos. It comprises a harzburgite tectonite mantle sequence with chromite mineralisation and a welldeveloped magma chamber with cyclic units ofdunite-lherzolite-wehrlite-pyroxenite that pass upwards into massive gabbros cut by diabase dykes and locally containing plagiogranite ponds. Ophiolite mineral and whole-rock chemistry are strongly in favour of a supra-subduction zone origin in a purely oceanic setting with the occasional brawny signature of melts from subducted sediments. By contrast, the basement amphibolites display a clear within-plate tholeiitic affinity with a slight imprint of subduction-zone fluids. Mineral stretching lineations and kinematics indicators of the orthogneisses and amphibolites suggest a consistent transport direction to the WSW. It is proposed that the basaltic protoliths of the amphibolites were emplaced during Permo-Triassic rifting of the eastern Pelagonian margin that led to the subsequent formation of the Vardar Ocean. The Titaros ophiolite was formed during closure of the Vardar Ocean via northeast-directed intra-oceanic subduction and subsequent obduction towards the southwest onto the eastern Pelagonian margin, probably in the Lower Cretaceous.

Article Details
  • Section
  • Mineralogy-Petrology-Geochemistry-Economic Geology
Downloads
Download data is not yet available.
References
Alabaster, T., Pearce, J., and Malpas, J., 1982. The volcanic stratigraphy and petrogenesis of the Oman ophiolite complex, Contributions to Mineralogy and Petrology, 81, 168-183, 1982.
Anders, B., 2005. The pre-Alpine evolution of the basement of the Pelagonian Zone and the Vardar Zone, Greece, Unpublished Ph.D. thesis, Johannes-Gutenberg-Universität Mainz, Germany, 140pp..
Anders, B., Reischmann, T., Kostopoulos, D., and Poller, U., 2006a. The oldest rocks of Greece: First evidence for a Precambrian terrane within the Pelagonian Zone, Geological Magazine, 143,41-58.
Anders, B., Reischmann, T., and Kostopoulos, D., 2006b. Zircon geochronology of basement rocks from the Pelagonian Zone, Greece: constraints on the pre-Alpine evolution of the westernmost Internal Hellenides, International Journal of Earth Sciences, DOI 10.1007/s00531-006-0121-7.
Anders, B., Reischmann, T., and Kostopoulos, D., 2007. Geochemistry, tectonic setting and provenance of basement rocks from the Pelagonian Zone, Greece, submitted.
Ballhaus, C, Berry, R.F., and Green, D.H., 1991. High pressure experimental calibration of the olivine-orthopyroxene-spinel oxygen geobarometer: implications for the oxidation state of the upper mantle, Contributions to Mineralogy and Petrology, 107, 27-40.
Beccaluva, L., Ohnenstetter, D., Ohnenstetter, M., and Paupy, Α., 1983. Two magmatic series with island-arc affinity within the Vourinos ophiolite, Contributions to Mineralogy and Petrology, 85, 253-271.
Bednarz, U., and Schmincke, H.-U., 1994. The petrological and chemical evolution of the northeastern Troodos extrusive series, Cyprus, Journal of Petrology, 35, 489-523.
Bertrand, P., and Mercier, J.-C.C, 1985. The mutual solubility of coexisting ortho- and clinopyroxene: toward an absolute geothermometer for the natural system? Earth and Planetary Science Letters, 76, 109-122.
Cameron, W.E., 1985. Petrology and origin of primitive lavas from the Troodos ophiolite, Cyprus, Contributions to Mineralogy and Petrology, 89, 239-255.
Devaraju, T.C., Raith, M.M., and Spiering, B., 1999. Mineralogy of the Archean barite deposit of Ghattihosahalli, Karnataka, India, Canadian Mineralogist, 37, 603-617.
Grapes, R.H., 1981. Chromian epidote and zoisite in kyanite amphibolite, Southern Alps, New Zealand, American Mineralogist, 66, 974-975.
Himmerkus, F., Anders, B., Reischmann, T., and Kostopoulos, D., 2007. Gondwana-derived terranes in the northern Hellenides, Geological Society of America Memoir, 200, in press.
Jaques, A.L., Chappell, B.W., and Taylor, S.R., 1983. Geochemistry of cumulus peridotites and gabbros from the Marum Ophiolite Complex, Northern Papua New Guinea, Contributions to Mineralogy and Petrology, 82, 154-164.
Kilias, Α., and Mountrakis, D., 1989. The Pelagonian nappe: Tectonics, metamorphism and magmatism. Bulletin of the Geological Society of Greece, 23/1, 29-46 (in Greek with English abstract).
Kostopoulos, D.K., 1989. Geochemistry, petrogenesis and tectonic setting of the Pindos ophiolite, NW Greece, Unpublished Ph.D. Thesis, University of Newcastle-upon-Tyne, U.K., 528 pp.
Kostopoulos, D.K., and James, S.D., 1992. Parameterisation of the melting regime of the shallow upper mantle and the effects of variable lithospheric stretching on mantle modal stratification and trace-element concentrations in magmas, Journal of Petrology, 33, 665-691.
McCulloch, M.T., and Cameron, W.E., 1983. Nd-Sr isotopie study of primitive lavas from the Troodos ophiolite, Cyprus: evidence for a subduction-related setting, Geology, 11, 727- 731.
Most, T., 2003. Geodynamic evolution of the eastern Pelagonian Zone in northwestern Greece and the Republic of Macedonia. Implications from U/Pb, Rb/Sr, K/Ar, 40Ar/39Ar geochronology and fission track thermochronology, Unpublished Ph.D. thesis, Eberhardt-Karls-Universität Tübingen, Germany, 98pp. + Appendices.
Mountrakis, D., 1983. The geological structure of the northern Pelagonian Zone and the geotectonic evolution of the Internal Hellenides. Habilitation thesis, Aristotle University of Thessaloniki, Greece, 289 pp. (in Greek with English summary).
Nagashima, M., Akasaka, M., and Sakurai, T. 2006. Chromian epidote in omphacite rocks from the Sambagawa metamorphic belt, central Shikoku, Japan, Journal of Mineralogical and Petrological Sciences, 101, 157-169.
Nance, D., 1981. Tectonic history of a segment of the Pelagonian zone, northeastern Greece, Canadian Journal of Earth Sciences, 18, 1111-1126.
Noiret, G., Montigny, R., and Allègre, C.J., 1981. Is the Vourinos complex an island arc ophiolite? Earth Planetary Science Letters, 56, 375-386.
Oze, C. J., LaForce, M.J., Wentworth, CM., Hanson, R.T., Bird, D.K., and Coleman, R.G., 2003.
Chromium geochemistry of serpentinous sediment in the Willow core, Santa Clara County, CA, U.S. Department of the Interior, U.S. Geological Survey, Open-File Report 03-251, 24pp.
Papanikolaou, D.J., 1997. The tectonostratigraphic terranes of the Hellenides. In D. J. Papanikolaou and. F. P. Sassi (eds), IGCP Project No: 276 Final Volume: Terrane Maps and Terrane Descriptions, Annales géologiques des pays helléniques, 37, 495-514.
Pearce, J.A., 1982. Chemical and isotopie characteristics of destructive margin magmas. In R.S. Thorpe (ed.), Andésites: Orogenic andésites and related rocks, pp. 525-548, John Wiley and Sons, Chichester.
Pearce, J.A., Alabaster, T., Shelton, A.W., and Searle, M.P., 1981. The Oman ophiolite as a cretaceous arc-basin complex: evidence and implications, Philosophical Transactions of the Royal Society of London, Series A 300, 299-317.
Pearce, J.Α., Harris, N.B.W., and Tindle, A.G., 1984. Trace element discrimination diagrams for the tectonic interpretation of granitic rocks, Journal of Petrology, 25, 956-983.
Plank, T., and Langmuir, C.H., 1998. The chemical composition of subducting sediment and its consequences for the crust and mantle, Chemical Geology, 145, 325-394.
Rassios, Α., Beccaluva, L., Bortolotti, V., Mavrides, Α., and Moores, E.M., 1983. The Vourinos ophiolite complex, Ofioliti, 8,275-292.
Rautenschlein, M., Jenner, G., Hertogen, J., Hofmann, A.W., Kerrich, J., Schmincke, H.-U., and White, W.E.M., 1985. Isotopie and trace element composition of volcanic glass from the Akaki Canyon, Cyprus: Implications for the origin of the Troodos ophiolite, Earth and Planetary Science Letters, 75, 369-383.
Reischmann, T., Kostopoulos, D.K., Loos, S., Anders, B., Avgerinas, Α., and Sklavounos, S.A., 2001. Late Palaeozoic magmatism in the basement rocks southwest of Mt. Olympos, central Pelagonian Zone, Greece: Remnants of a Permo-Carboniferous magmatic arc, Bulletin of the Geological Society of Greece, XXXIV/3, 985-993.
Reischmann, T., and Kostopoulos, D., 2007. Terrane accretion in the internal Hellenides, Geophysical Research Abstracts, 9, 05337.
Robinson, P.T., Melson, W.G., O'Hearn, T., and Schmincke, H.-U., 1983. Volcanic glass compositions of the Troodos ophiolite, Cyprus, Geology, 11, 400-404.
Schermer, E.R., 1993. Geometry and kinematics of continental basement deformation during the Alpine orogeny, Mt. Olympos region, Greece, Journal of Structural Geology, 15, 571-591.
Stampili, G.M., and Borei, G.D., 2002. A plate tectonic model for the Paleozoic and Mesozoic constrained by dynamic plate boundaries and restored synthetic oceanic isochrones, Earth and Planetary Science Letters, 196, 17-33.
Treloar, P.J., 1987. Chromian muscovites and epidotes from Outokumpu, Finland, Mineralogical Magazine, 51,593-599.
Yarwood, G.A., and Aftalion, M. 1976. Field relations and U-Pb geochronology of a granite from the Pelagonian zone of the Hellenides (High Pieria, Greece), Bulletin de la Société Géologique de France, 7, 259-264.
Yarwood, G.A., and Dixon, J.E., 1979. Lower Cretaceous and younger thrusting in the Pelagonian rocks of the High Pieria, Greece, Vf Colloquium Géologique de Régions Egéenes (Athens, 1977), 269-280.
Zachariadis, P., Reischmann, T., and Kostopoulos, D., 2006. U-Pb ion-microprobe zircon dating of subduction-related magmatism from northern Greece: The ages of the Guevgueli, Thessaloniki and Chalkidiki igneous complexes, Geophysical Research Abstracts, 8, 05560.
Most read articles by the same author(s)