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Mineralogy and Petrology

, Volume 92, Issue 3–4, pp 393–413 | Cite as

Petrology of eclogites from north of Shahrekord, Sanandaj-Sirjan Zone, Iran

  • A. R. Davoudian
  • J. Genser
  • E. Dachs
  • N. Shabanian
Article

Summary

Metabasic rocks were recently found within a ductile shear zone in the north of Shahrekord, being a part of the structural zone of Sanandaj-Sirjan, SW Iran. The rocks give evidence of a so far unrecognized eclogite facies metamorphic event and testify to high pressure metamorphism in the Sanandaj-Sirjan Zone, near the Main Zagros Reverse Fault, which is the assumed suture zone between the Arabian plate and the Iranian block. The eclogites occur as lenses or blocks within ortho- and paragneisses. The petrographic features and reaction textures display at least two main metamorphic stages: (1) a peak eclogite facies stage, and (2) a subsequent amphibolite facies stage. The eclogite facies metamorphism is indicated by omphacite + garnet + sodic-calcic amphiboles (barroisite, magnesiokatophorite and magnesiotaramite) + phengite + rutile + (clino-)zoisite + quartz ± dolomite. The garnets are mainly almandine-rich, which fits with the C-type eclogite classification. Calcic amphiboles (hornblende, tschermakite and pargasite) + plagioclase are secondary phases formed during the retrograde amphibolite-facies metamorphism. P-T estimates for the eclogite facies give pressures of 21–24 kbar and temperatures of 590–630 °C (geothermometry) and 470–520 °C (THERMOCALC), respectively. Geothermobarometry for the amphibolite-facies metamorphism yields 10–11 kbar and 650–700 °C.

Keywords

Rutile Contrib Mineral Petrol Arabian Plate Ductile Shear Zone Plane Polarize Light 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. Agard, P, Omrani, J, Jolivet, L, Mouthereau, F 2005Convergence history across Zagros (Iran): constraints from collisional and earlier deformationInt J Earth Sci94401419CrossRefGoogle Scholar
  2. Ai, Y 1994A revision of the garnet-clinopyroxene Fe2+-Mg exchange geothermometerContrib Mineral Petrol115467473CrossRefGoogle Scholar
  3. Alavi, M 1994Tectonics of the Zagros orogenic belt of Iran: new data and interpretationsTectonophysics229211238CrossRefGoogle Scholar
  4. Anderson, JL, Smith, DR 1995The effects of temperature and oxygen fugacity on the Al-in-hornblende barometerAm Mineral80549559Google Scholar
  5. Bellot, JP, Triboulet, C, Laverne, C, Bronner, G 2003Evidence for two burial/exhumation stages during the evolution of the Variscan belt, as exemplified by P-T-t-d paths of metabasites in distinct allochthonous units of the Maures massif (SE France)Int J Earth Sci92726Google Scholar
  6. Berberian, M, King, GC 1981Towards a paleogeography and tectonics evolution of IranCan J Earth Sci18210265Google Scholar
  7. Berman, RG, Aranovich, LY, Pattison, DRM 1995Reassessment of the garnet-clinopyroxene Fe-Mg exchange thermometer: II. Thermodynamic analysisContrib Mineral Petrol1193042CrossRefGoogle Scholar
  8. Carswell, DA 1990Eclogite facies rocksBlackieGlasgow and LondonGoogle Scholar
  9. Coleman, RG, Lee, DE, Beatty, LB, Brannock, WW 1965Eclogites and eclogites: their differences and similaritiesGeol Soc Am Bull76483508CrossRefGoogle Scholar
  10. Dachs, E 1998PET: Petrological elementary tools for mathematicaComput Geosci24219235CrossRefGoogle Scholar
  11. Dachs, E 2004PET: Petrological elementary tools for mathematica: an updateComput Geosci30173182CrossRefGoogle Scholar
  12. Dale, J, Holland, TJB, Powell, R 2000Hornblende-garnet-plagioclase-thermobarometry: a natural assemblage calibration of the thermodynamics of hornblendeContrib Mineral Petrol40353362CrossRefGoogle Scholar
  13. Davoudian AR (2005) The tectonometamorphic and magmatic evolution in the Shahrekord-Daran area (Sanandaj – Sirjan Zone, Iran), PhD Thesis, University of Isfahan, Iran, pp 220Google Scholar
  14. Davoudian, AR, Khalili, M, Noorbehsht, I, Dachs, E, Genser, J, Shabanian, N 2006Geochemistry of metabasites in the north of the Shahrekord, Sanandaj – Sirjan Zone, IranN Jb Mineral Abh182291298CrossRefGoogle Scholar
  15. Deer, WA, Howie, RA, Zussman, J 1992An introdution to the rock-forming mineralsLongman Scientific & TechnicalHarlow, EnglandGoogle Scholar
  16. Dewey, JF, Pitman, WC, Ryan, WBF, Bonnin, J 1973Plate tectonics and the evolution of the Alpine SystemGeol Soc Am Bull8431373180CrossRefGoogle Scholar
  17. Droop, GTR 1987A general equation for estimating Fe+3 concentrations in ferromagnesian silicates and oxides from microprobe analyses, using stoichiometric criteriaMineral Mag51431435CrossRefGoogle Scholar
  18. Ellis, DJ, Green, DH 1979An experimental study of the effect of Ca upon garnet-clinopyroxene Fe-Mg exchange equilibriaContrib Mineral Petrol76413419Google Scholar
  19. Ernst, WG, Liu, J 1998Experimental phase-equilibrium study of Al- and Ti-contents of calcic amphibole in MORB – A semiquantitative thermobarometerAm Mineral83952969Google Scholar
  20. Ganguly, J, Cheng, W, Tirone, M 1996Thermodynamics of aluminosilicate garnet solid solution: new experimental data, an optimized model, and thermometric applicationsContrib Mineral Petro1126137151CrossRefGoogle Scholar
  21. Ghasemi, A, Talbot, CJ 2006A new tectonic scenario for the Sanandaj-Sirjan Zone (Iran)J Asian Earth Sci26683693CrossRefGoogle Scholar
  22. Ghent, ED 1988A review of chemical zoning in eclogite garnetsSmith, DC eds. Eclogite and eclogite-facies rocksElsevierAmsterdam217231Google Scholar
  23. Graham, CM, Powell, R 1984A garnet-hornblende geothermometer: calibration, testing and application to the Pelona Schist, southern CaliforniaJ Metamorph Geol21321CrossRefGoogle Scholar
  24. Green, DH, Ringwood, AE 1967An experimental investigation of the gabbro to eclogite transformation and its petrological applicationsGeochim Cosmochim Acta31767833CrossRefGoogle Scholar
  25. Green, TH, Hellman, PL 1982Fe-Mg partitioning between coexisting garnet and phengite at high pressure, and comments on a garnet-phengite geothermometerLithos15253266CrossRefGoogle Scholar
  26. Haynes, JR, McQuillan, H 1974Evolution of the Zagros Suture Zone, Southern IranGeol Soc Am Bull85739744CrossRefGoogle Scholar
  27. Holland, T, Blundy, J 1994Non-ideal interactions in calcic amphiboles and their bearing on amphibole-plagioclase thermometryContrib Mineral Petro116433447CrossRefGoogle Scholar
  28. Holland, TJB 1980The reaction albite = jadeite + quartz determined experimentally in the range 600–1200 8CAm Mineral65129134Google Scholar
  29. Holland, TJB 1990Activities of components in omphacitic solid solutions. An application of Landau theory to mixturesContrib Mineral Petro1105446453CrossRefGoogle Scholar
  30. Holland, TJB, Powell, R 1998An internally consistent thermodynamic data set for phases of petrological interestJ Metamorph Geol16309343CrossRefGoogle Scholar
  31. Hoschek, G 2007Metamorphic peak conditions of eclogites in the Tauern Window, Eastern Alps, Austria: thermobarometry of the assemblage garnet + omphacite + phengite + kyanite + quartzLithos93116CrossRefGoogle Scholar
  32. Kretz, R 1983Symbols for rock-forming mineralsAm Mineral68277279Google Scholar
  33. Krogh, EJ 1980Geochemistry and petrology of glaucophane-bearing eclogites and associated rocks from Sunnfjord, western NorwayLithos13355380CrossRefGoogle Scholar
  34. Krogh, EJ, Raheim, A 1978Temperature and pressure dependence of Fe-Mg partitioning between garnet and phengite with particular reference to eclogitesContrib Mineral Petrol667580CrossRefGoogle Scholar
  35. Krogh Ravna, E, Terry, MP 2004Geothermobarometry of UHP and HP eclogites and schists – an evaluation of equilibria among garnet-clinopyroxene-kyanite-phengite-coesite/quartzJ Metamorph Geol22579592CrossRefGoogle Scholar
  36. Krogh Ravna, RE 2000The garnet-clinopyroxene Fe2+-Mg geothermometer: an updated calibrationJ Metamorph Geol18211219CrossRefGoogle Scholar
  37. Leake, BE the IMA Commission1997Nomenclature of amphiboles. Report of the Subcommittee on Amphiboles of the International Mineralogical Association on New Minerals and Mineral NamesEur J Mineral9623651Google Scholar
  38. Macquarie, M 2004Crustal scale geometry of the Zagros fold-thrust belt, IranJ Struct Geol26519535CrossRefGoogle Scholar
  39. McQuarrie, N, Stock, JM, Verdel, C, Wernicke, BP 2003Cenozoic evolution of Neotethys and implications for the causes of plate motionsGeophys Res Lett3014CrossRefGoogle Scholar
  40. Mohajjel, M, Fergusson, CL 2000Dextral transpression in late Cretaceous continental collision, Sanandaj-Sirjan Zone, Western IranJ Struct Geol2211251139CrossRefGoogle Scholar
  41. Mohajjel, M, Fergusson, CL, Sahandi, MR 2003Cretaceous-Tertiary convergence and continental collision, Sanandaj-Sirjan Zone, western IranJ Asian Earth Sci21397412CrossRefGoogle Scholar
  42. Morimoto, N, Fabries, J, Ferguson, AK, Ginzburg, IV, Ross, M, Seifert, FA, Zussman, J, Aoki, K, Gottardi, G 1988Nomenclature of pyroxenesMineral Mag52535550CrossRefGoogle Scholar
  43. Mysen, BO, Griffin, WL 1973Pyroxene stoichiometry and the breakdown of omphaciteAm Mineral586063Google Scholar
  44. Peacock, SM 1995Ultrahigh-pressure metamorphic rocks and the thermal evolution of continent collision beltsIsland Arc4376383CrossRefGoogle Scholar
  45. Powell, R 1985Regression diagnostic and robust regression in geothermometer/geobarometer calibration: the garnet-clinopyroxene geothermometer revisitedJ Metamorph Geol3327342CrossRefGoogle Scholar
  46. Powell, R, Holland, TJB 1988An internally consistent thermodynamic dataset with uncertainties and correlations: 3. Application, methods, worked examples and a computer programJ Metamorph Geol6173204CrossRefGoogle Scholar
  47. Rashidnejad-Omran, N, Emami, MH, Sabzehei, M, Rastad, E, Bellon, H, Pique, A 2002Lithostratigraphie et histoire paléozoïque à paléocène des complexes métamorphiques de la région de Muteh, zone de Sanandaj-Sirjan (Iran méridional)C. R. Geoscience33411851191CrossRefGoogle Scholar
  48. Roland, FB, Tracy, RJ 1991P-T paths from zoned garnets: some minimum criteriaAm J Sci291917939CrossRefGoogle Scholar
  49. Sabzehei M (1996) An introduction to general geological features of metamorphic complexes in southern Sanandaj-Sirjan zone. Geol. Surv. Iran (Unpublished, in Persian)Google Scholar
  50. Sassi, R, Mazzoli, C, Miller, C, Konzett, J 2004Geochemistry and metamorphic evolution of the Pohorje Mountain eclogites from the easternmost Austroalpine basement of the Eastern Alps (Northern Slovenia)Lithos78235261CrossRefGoogle Scholar
  51. Sengör AMC (1984) The cimmeride orogenic system and the tectonics of Eurasia, Geological Society of America Special Paper, 195Google Scholar
  52. Sengör, AMC, Natal’in, BA 1996Paleotectonics of Asia: fragments of a synthesisYin, AHarrison, TM eds. The tectonic evolution of AsiaCambridge University PressCambridge486640Google Scholar
  53. Spear, FS 1991On the interpretation of peak metamorphic temperatures in light of garnet diffusion during coolingJ Metamorph Geol9379388CrossRefGoogle Scholar
  54. Sepehr, M, Cosgrove, JW 2004Structural framework of the Zagros Fold-Thrust Belt, IranMar Petrol Geol21829843CrossRefGoogle Scholar
  55. Stöcklin, J 1968Structural history and tectonics of Iran: a reviewAm Assoc Petroleum Geol Bull5212291258Google Scholar
  56. Tsujimori, T, Matsumoto, K, Wakabayashi, J, Liou, JG 2006Franciscan eclogite revisited: reevaluation of the P-T evolution of tectonic blocks from Tiburon Peninsula, California, U.S.AMineral Petrol88243267CrossRefGoogle Scholar
  57. Waters, DJ, Martin, HN 1993Geobarometry of phengite-bearing eclogitesTerra Abstracts5410411Google Scholar
  58. Will, TM, Schmädicke, E 2001A first find of retrogressed eclogites in the Odenwald crystalline Complex, Mid-German Crystalline Rise, Germany: evidence for a so far unrecognized high-pressure metamorphism in the Central VariscidesLithos59109125CrossRefGoogle Scholar
  59. Zack, T, Kronz, A, Foley, SF, Rivers, T 2002Trace element abundances in rutiles from eclogites and associated garnet mica schistsChem Geol18497122CrossRefGoogle Scholar
  60. Zahedi M, Rahmati-Ilkhchi M, Vaezipour J (1992) Geological map of the Shahrekord Quadrangle E8. 1:250000, Geological Survey of Iran, Tehran, IranGoogle Scholar

Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • A. R. Davoudian
    • 1
  • J. Genser
    • 2
  • E. Dachs
    • 3
  • N. Shabanian
    • 4
  1. 1.Department of Natural ResourcesShahrekord UniversityShahrekordIran
  2. 2.Department of Geography and GeologySalzburg UniversitySalzburgAustria
  3. 3.Department of Material Science and PhysicsSalzburg UniversitySalzburgAustria
  4. 4.Payame Noor UniversityIran

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