Document Type : Original Research Paper

Authors

1 Ph.D. Student, Department of Geology, Shahid Bahonar University of Kerman, Kerman, Iran

2 Associate Professor, Department of Geology, Shahid Bahonar University of Kerman, Kerman, Iran

3 Professor, Department of Earth Sciences, University of Tabriz, Tabriz, Iran

Abstract

The study area is a part of the Sanandaj-Sirjan zone which is mainly composed of metamorphic rocks, a variety of igneous basic rocks and sediments. the metamorphic rocks studied at west of Kheyrabad, North of Gol-e Gohar mine in Sirjan, Kerman Province are slate, phyllite, schist (garnet schist, amphibole schist, micaschist, kyanite schists), epidote amphibolite, amphibolite, gneiss, quartzite and marble. Amphibolite facies is the highest metamorphic grade in the region experienced by the rocks. Protolith of amphibolites is basic to intermediate igneous rocks with chemical composition of calc-alkaline. Based on Ti against V diagram and Nb-Zr-Ydiagram, amphibolites of the study area belong to mid-ocean ridges (MOR) and Volcanic arc tectonic environments in relation to Neotethys ocean.Mineral chemical features classify amphiboles as calcic amphiboles. average temperature of  amphiboles is  630°C and maximum pressure is 7.5 kbar for the studied amphibolites. Geothermal gradient of ~ 28°C/Km indicates a continental crust setting for metamorphism.

Keywords

References
Ahmed-Said, Y. and Leake, B.E., 1997- The petrogenesis of the Edoughamphibolites, Annaba, NE Algeria: two unrelated basic magmas and the lherzolite-harzburgite residue of a possible magma source. – Mineralogy and Petrology, 59: 207-237.
Blundy, J. and Holland, T.J., 1990- Calcic amphibole equilibria and a new amphibole-plagioclase geothermometer.  Contributions to Mineralogy and Petrology 104, 208–224.
Brown, E.H., 1977- The crosstie content of Ca-amphibole as a guide to pressure of metamorphism. Journal of Petrology 18, 53-72.
Colombi, A., 1989- Me ´tamorphism et ge ´ochimie des rochesmafiques des Alpesouest-centrales (géoprofil Vie `ge-DomodossolaLocarno). Mem Geol Lausanne 4.
Dimitrijevic, M.D., 1973- Geology of  Kerman  region. Geological  Survey of Iran, YU/52.
Ernst, W. and Liu, J., 1998- Experimental phase-equilibrium study of Al-and Ti-contents of calcic amphibole in MORB- A semi-quantitative thermobarometer. American Mineralogist 83(9-10), 952-969.
Garrels, R. M. and Mackenzie, F.T., 1971- Evolution of sedimentary rocks. W. W. Norton and Co., New York. 397 p.
Hastie, A. R., Kerr, A. C., Pearce, J. A. and Mitchell, S. F., 2007- Classification of altered volcanicisland arc rocks using immobile trace elements: development of the Th Co discrimination diagram. Journal of Petrology 48, 2341–2357.
Holland, T. and Blundy, J., 1994- Non-ideal interactions in calcic amphiboles and their bearing on amphibole-plagioclase thermometry. Contributions to Mineralogy and Petrology 116(4), 433-447.
Laird, J., Lanphere, M. A. and Albee, A. L., 1984- Distribution of Ordovician and Devonian metamorphism in mafic and pelitic schists from northern Vermont. American Journal of Science, 284(4-5), 376-413.
Leake, B.E., Woolley, A.R., Arps, C.E., Birch, W.D., Gilbert, M.C., Grice, J.D. and Krivovichev, V.G., 1997- Nomenclature of amphiboles; report of the subcommittee on amphiboles of the International Mineralogical Association, Commission on New Minerals and Mineral Names. American Mineralogist 82, 1019–1037.
Meschede, M., 1986- A method of discriminating between different types of mid-oceanridge basalts and continental tholeiites with the Nb-Zr-Y diagram. ChemicalGeology, 56:207-218.
Mohajjel, M., Fergusson, C. L. and Sahandi, M. R., 2003- Cretaceous–Tertiaryconvergence and continental collision, Sanandaj-Sirjan zone, WesternIran.Journal of Asian Earth Sciences, 21 397–412.
Pearce, J.A., 1983- Role of the sub-continental lithosphere in magma genesis atactive continental margins.In Continental basalts and mantle xenoliths.Edited by C.J. Hawkesworth and M.J. Norry.Shiva Publishing Ltd., Cheshire, United Kingdom.
Pearce, J.A. and Norry, M.J., 1979-Petrogenetic implications of Ti, Zr, Y, and Nb variations in volcanic rocks. Contributions to Mineralogy and Petrology 69 (1), 33–47.
Poller, U., Huth, J., Hoppe, P. and Williams, I.S., 2001- REE, U, Th, and Hf distribution in zircon from western Carpathian Variscangranitoids: a combined cathodoluminescence and ion microprobe study. – American Journal of Science, 301: 858-876.
Saki, A., Moazzen, M. and Oberhänsli, R., 2011- P-T evolution of the Precambrian metamorphic complex, NW Iran: a study of metapelitic rocks. Geological Journal 46, 10-25.
Shervais, J. W., 1982- Ti-V plots  and the petrogenesis of modern abdophiolitic Lavas. Earth and Planetary Science Letters, 59:101-118.
Walker, K. R., Jopin, G. A., Lovering, J. F. and Green, R., 1960- Meta­morphic and metasomatic convergence of basic igneous rocks and lime­magnesia sediments of the Precambrian of north-western Queensland. Journal of the Geological Society of Australia 6, 149-178.
Winchester, J.A. and Floyd, P.A., 1976- Geochemical magma typediscrimination: application to altered and metamorphosed basic igneous rocks. Earth and Planetary Science Letters, 28: 459-469.
Wood, D., Joron, J.-L., Treuil, M., Norry, M. and Tarney, J., 1979- Elemental and Sr isotope variations in basic lavas from Iceland and the surrounding ocean floor. Contributions to Mineralogy and Petrology 70 (3), 319–339.
Yihunie, T., Adachi, M. and Yamamoto, K., 2006- Geochemistry of the Neoproterozoic metabasic rocks from the Negele area, southern Ethiopia: Tectonomagmatic implications. – Journal of African Earth Sciences, 44: 255-269