Petrography, geochemistry, petrogenesis and microstructure of the metamorphic rocks from northeast Songhor

Document Type : Research Paper

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Abstract

The study area is the part of Sanandaj – Sirjan zone and  is located in the north of  Songhor. This area consists of various metamorphic rocks with igneous and sedimentary protoliths. All types of existing rocks are metamorphosed in the greenschist facies. The metamorphosed rocks consist of metagranite, metavolcanics, marble, schist, calc-schist, calc-silicates, green schist, slate and phyllite. The textures of present rocks are often blastoporphyric, granoblastic and lepidoblastic. On Harker diagrams, the K2O values are increasing while SiO2 increasing, whereas, TiO2, MgO and FeOt are decreasing, therefore, the differentiation is probably the most important process in the chemical development of the rocks. Volcanic rocks are calc- alkaline and enriched in large ion lithophile elements such as K, Rb and depleted in high field strength elements such as Ti, Nb. The intrusive bodies are granites intruding the metamorphic rocks. Granites are weakly peraluminous and calc-alkaline and according to tectonic diagrams belong towithin-plate granites(WPG). The rocks were deformed by tectonic forces and different microstructures formed that is indicating the existence of different phases of deformation in the area.

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References

[1] اشراقی، ص. ع.، جعفریان، م. ب و  اقلیمی، ب (1375) نقشه­ی  100000/1 سنقر، سازمان زمین شناسی و اکتشافات معدنی کشور.
[2] افتخارنژاد، ج (1391) جزوه درسی، زمین شناسی ایران و کشورهای همجوار، دانشگاه شهید بهشتی.
[3] حسینی، ب (1389) پترولوژی و پتروژنز سنگ­های دگرگونی منسوب به پالئوزوئیک در زون سنندج - سیرجان و ارتباط آن­ها با کانی­سازی آهن، رساله­ی دکتری، دانشگاه شهید بهشتی.
[4] قربانی، م (1381) دیباچه­ای بر زمین­شناسی اقتصادی ایران، سازمان زمین­شناسی و اکتشافات معدنی کشور، 700 صفحه.
[5] قربانی، م (1392)  ماگماتیسم و متامورفیسم ایران،  انتشارت آرین زمین.
[6] کریم­زاده ثمرین، ع. ر (1391) کاربرد داده­های ژئوشیمیایی: ارزیابی، نمایش، تفسیر، دانشگاه تبریز، تالیف هاگ رولینسون، ترجمه، 557 صفحه.
[7] کنعانیان، ع (1390) فرآیندهای موثر در تکوین توده نفوذی کوه دم، شمال­خاور اردستان: با تکیه بر شواهد ژئوشیمیایی و ایزوتوپی، مجله علوم زمین، سال21، شماره81، صفحه 191-200.
[8] کیوانلو، ز (1390) زمین­شناسی، کانی­شناسی، ژئوشیمی و پترولوژی سنگ­های اطراف روستای سنگ­سفید، پایان نامه­ی کارشناسی­ارشد، دانشگاه فردوسی مشهد.
[9] مظفرزاده، ر (1382) پتروگرافی، ژئوشیمی و پتروژنز سنگ­های آذرین و دگرگونی محور معادن گلالی- باباعلی (شمال­شرق سنقر)، پایان­نامه­ی کارشناسی­ارشد، دانشگاه شهید بهشتی.
[10]   Barker, A (1991) Introduction to metamorphic textures and microstructures. Blackie, NEW YORK.
[11]   Cox, K. g., Bell, J. D., & Pakhurst, R. J (1979) The interpretation of igneous rocks Allen and unwin, London, 450 pp.
[12]   Dewers, T., & Ortoleva, P (1990) Differentiated structures arising from mechano-chemical feedback in stressed rockes. Earth-Science Reviews, 29: 283-298.
[13]   Dunne, W.M., & Hancock, P.L (1994) Palaeostress analysis of small-scale brittle structures. In: Continental deformation (ed. Hancock, P.) 101-120. Pergamon Press, Oxford.
[14]   Gratier, J.P., Muquet, L., Hassani, R., & Renard, F (2005) Exprimental microstylolites in quartz and modelled application to natural stylolitic structures. Structural Geology, 27: 89-100.
[15]   Harker, A (1909) The natural history of igneous rocks. Methuen and Co., London.
[16]   Irvine T.N., & Baragar W.R.A (1971) Aguide to the chemical classification of the common volcanic rocks. Canadian Journal Earth Science, 8: 523-548.
[17]   Karcz, Z., & Scholz, C.H (2003) The fractal geometry of some stylolites from the Calcare Massiccio Formation, Italy. Structural Geology, 25: 1301-1316.
[18]   Karsli, O., Chen, B., Aydin, F. & Şen, C (2007) Geochemical and Sr–Nd–Pb isotopic compositions of the Eocene Dölek and Sariçiçek Plutons, Eastern Turkey: Implications for magma interaction in the genesis of high-K calc-alkaline granitoids in a post-collision extensional setting, Lithos, 98: 67-96.
[19]   Middlemost, E.A.K (1985) Magmas and magmatic rock. Longman, London.
[20]   Middlemost, E.A.K (1994) Naming materials in the magma/igneous rock system.Earth-Sciencereviews, 37: 215-224.
[21]   Miyashiro, A (1973) Metamorphic and metamorphic belts.George Allen & Unwin, Lodon.
[22]   Passchier, C. W., & Trow, R. A. J (2005) Microtectonic. 2nd edition, Springer, Verlag, Berlin. 365p.
[23]   Pearce, J. A (1980) Geochemical evidence for the genesis and eruptive setting of lavas from Tethyan ophiolites. Proc. I nt. ophiolite Symp., Gyprus 1979. Institute of Mining and Metallurgy, pp. 261- 272.
[24]   Pearce, J. A., Harris, N.B.W. and Tindle, A.G (1984) Trace element discrimination diagrams for the tectonic Interpretation of granitic rocks. Geol , Soe. Spec.Publ, 7: 14– 24.
[25]   Peccerillo, A., & Taylor, S. R (1976) Geochemistry of Eocene calc-alkaline volcanic rocks from the Kastamonu area, Northern Turkey. Contributions toMineralogy and Petrology, 58: 63–81.
[26]   Petit, JP., & Matthauer, M (1995) Paleostress superimposition deduced from mesoscale structures in limestone: the Matelles exposure, Languedoc, France. Structural Geology, 17: 245-256.
[27]   Prior, DJ (1993) Sub-critical fracture and associated retrogression of garnet duringmylonitic deformation. Contributions to Mineralogy and Petrology, 113: 545-556.
[28]   Railsback, L.B., &  Andrews, L.M (1995) Tectonic stylolites in the  undeformed Cumberland Plateau of southern Tennessee. Structural Geology, 17: 911-922.
[29]   Railsback, L.B (1998) Evaluation of spacing of stylolites and its implication for self-organizationes of pressure dissolution. Sedimentary Petrology, 68: 2-7.
[30]   Renard, T., Schmittbuhl, J., Gratier, J.P., Meakin, P., & Merino, E (2004) Threedimentional roughness of stylolites in limestones. Geophysical Research, 109, B03209
[31]   Rollinson, H (1993) Usiong geochemical data: evaluation, presentation, interpretation: Longman Group Publi. - Stockdale, PB., (1922). Stylolites: their nature and origin. Indiana University Studies, 9: 1-97.
[32]   Shand, S.J (1943) "The Eruptive Rocks" John Wiley. New York.
[33]   Stockdale, PB (1922) Stylolites: their nature and origin. Indiana University Studies, 9: 1-97.
[34] Stoclin, J (1968) Structural history and tectonics of Iran: a review. American  AssociationPetroleum Geologists Bulletin, 25: 1229-1258.
[35]   Sun, S.S.,  & McDonough, W.F (1989) Chemical and isotopic systematics of oceanic basalts: implications for mantle composition and processes. In: Saunders, A.D., Norry, M.J. (Eds.), Magmatism in ocean basins, vol. 42. Geological Society of London Special Publication. 429–448.
[36]   Thompson, R. N (1982) British Tertiary volcanic province. Scott. J. Geol, 18: 49-107.

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  • Receive Date: 23 February 2015
  • Revise Date: 12 April 2016
  • Accept Date: 17 May 2015

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