Geochemistry and tectonic setting of the A-type granitoid, in Mishu mountains, northwest of Iran (Shabestar city)

Document Type : Original Article

Authors

1 Department of Geology, Faculty of Sciences, slamic Azad University, Shabestar Branch, Shabestar, Iran

2 Department of Geology, Faculty of Natural Sciences, Tabriz University, Tabriz, Iran

Abstract

Introduction
Granitic to alkaline feldspar granitic masses of Mishu mountains, which are similar to them in the Moro mountains in the northwest of the country, are among the granitoid masses that are related to the Hercynian (Donian-Permian) orogenic cycle, and the study of their lithology and petrogenesis in order to complete the geological information. The northwest of the country is of particular importance and they contribute to our knowledge of the crustal formation of Iran during the Hercynian orogeny (Moayyed and Moazzen, 2002). Eftekharnejad et al. (1991) considered the mass of intrusive Shebster to be equivalent to Mishu granites. This massif has cut and transformed the Kahr and Dolomites of Sultanate. Permian base sediments were placed on the eroded surface of this intrusive mass and based on this, the age of this mass has been attributed to Post-Cambrian and Pre-Permian (Asadian et al, 1994). Due to the lack of determination of the A-type granites and the existence of some ambiguities about the Shabestar granitoid mass such as lithology and geochemistry (including the temporal relationship of the Shabestar granite mass with the adjacent masses and the orogenic phase of Iran), the Shabestar intrusive mass requires a comprehensive and comprehensive study to be a part of the history The geology of this area and the granite masses of the adjacent areas should be properly analyzed. Therefore, in this article, with the help of the results obtained from the study of the field relationships governing the different parts of the Shabaster intrusive mass, petrography and geochemical analysis of the main and rare elements, it has been tried to investigate the genetic relationship between the different parts of the mass, the origin of the magma that formed it, and the tectonic position of this intrusive mass. And finally, determine the A-type granites and compare them with S and I granites.
 
Materials and Methods
In general, conducting this research includes two stages of field visits and laboratory investigations. 
In the first surveys and field visits, 150 stone samples were taken from the internal igneous (Granitoid) masses of Shabestar, and from these samples, 110 microscopic thin sections were prepared for petrographic studies. In the next step, 20 samples were sent to ACME laboratory in Canada for geochemical analysis by whole rock method. Oxide analysis of main elements was done by lithium borate fusion method and inductively coupled plasma emission spectrometer (ICP-ES). In this method, the amount of oxides of the main elements is measured based on weight percentage.
 
Results and Discussion
Alkaline mafic minerals such as ezirin-augeite and ribkeite-arphodsonite are not found in the examined granites, but all petrographic and geochemical data show that Harris granite rocks are of A-type nature. The comparison of the granite mass of East Mishu with the granite mass of Harris shows that this mass has a range of alkaline rocks of granite-monzogranite-siyenogranite. The dominant texture in these samples is fine-grained from the same dimension to the non-dimensional, perthitic and granophyric. The main minerals of these stones include quartz, potassium feldspar, plagioclase and minor and accessory minerals including biotite, amphibole, pyroxene, apatite, sphene and zircon, which are similar to the granites studied in this article. The negative anomalies of Ba, Nb, Ti, Sr, and Eu and the enrichment in LILEs, especially Rb and Thn, indicate the crustal origin of these rocks. Also, Ce and Sm show their enrichment compared to the adjacent elements. Such selective enrichment has been referred to as shell dominance (Pearce et al, 1984), and such a pattern is called shell dominance. In addition, these high values of HFSEs confirm the dry origin of the constituent magma (Bonin, 2007; Zhao and Zhou, 2007).
 
Conclusion
According to the field evidence, petrography, geochemistry and tectonic structure differentiation diagrams, Shabester granitoid mass is alkali feldspar granite. These rocks are covered by the Permian Formation and the Soltanieh Formation has recrystallized with it. Therefore, their relative age is attributed to Post-Cambrian and Pre-Permian. According to the alumina saturation index, the granitoid mass of Shabestar has peraluminous to weakly metaaluminous characteristics. Negative anomalies of Ba, Nb, Ti, Sr and Eu and enrichment in LILEs, especially Rb and Thn, indicate the crustal origin of these rocks. Therefore, Shabestar granitoid mass is A-type of in-plane granites of A-type, which is related to group A2 due to the depletion of Nb. In other words, it is very likely that A-type alkaline granites were created in this region after impact events, and during their emplacement, tensile tectonics prevailed. The REE diagram of these granites shows that the granitoid mass of Shabestar was probably due to partial melting of the lower crust with tonalitic-granodioric composition. The REE diagram of these granites shows that the granitoid mass of Shabestar was obtained from a plagioclase-containing source, or plagioclase was separated from the forming magma during the evolutionary process, so that it is probably due to partial melting of the lower crust with tonalitic-granodioric composition.

Keywords

Main Subjects


Abdel Rahman, A.M., 2006. Petrogenesis of anorogenic peralkaline granitic complexes from eastern Egypt. Mineralogical Magazine, v. 70(1), p.  27-50.
Advay, M., Jahangiri, A., Mojtahedi, M. and Ghalamghash, J., 2010. Petrology and Geochemistry of Shah Ashan Dagh Mafic Rocks and A-type Granite in NE of Khoy, NW Iran. Scientific Quarterly Journal, Geosciences, v. 20(77), p.  83-90. (In Persian with English abstract) http://dx.doi.org/10.22071/gsj.2010.55342
Aghanabati, A., 2004. The Geology of Iran. Geological Survey of Iran, Tehran, 586 p (In Persian).
Ahankoub, M., 2011. Petrogenesis and geochemistry of granitoids east of Mishov Mountains, northwest of Iran. PhD Thesis, University of Tabriz, Tabriz, Iran, 120 p (in Persian).
Ahankoub, M., Jahangiri, A. and Moayyed, M., 2012. Study of the effect of tetrad on the pattern of rare earth elements in the A-Type Mishu granitoid assemblage in northwestern Iran. Iranian Journal of Petrology, v. 3(10), p. 65-78. (In Persian with English abstract) Retrieved January 2, 2022 from https://ijp.ui.ac.ir/article_16099.html
Aliani, F., Maanijou, M. and Miri, M., 2012. Petrology of the Tekyeh-Bala area granite veins (northeast of Sonqor), some evidences for A2-type granitoids, Iranian Journal of Petrology, v. 3(9), p. 1-16 (In Persian with English abstract) Retrieved January 2, 2022 from https://ijp.ui.ac.ir/article_16091.html
Amini, S., Ravankhah, A. and Moayed, M., 2007. Petrology and lithogenesis of igneous masses of Divan Daghi - Qara Goz, North Marand (East Azerbaijan). Iranian Journal of Crystallography and Mineralogy, v. 16(2), p. 249-264 (In Persian with English abstract) Retrieved January 2, 2022 from https://ijcm.ir/article-1-637-en.html
Asadian, O., Mirzaee, A.R., Mohajjel, M. and Hadjialilu, B., 1994. Geological map of Marand. scale 1:100000 Geological Survey of Iran (In Persian).
Asadpour, M., Pourmoafi, S.M. and Heuss, S., 2013. Geochemistry, petrology and U-Pb geochronology of Ghazan mafic-ultramafic intrusion, NW Iran. Iranian Journal of Petrology, v. 4(14), p. 1-16 (In Persian with English abstract) Retrieved January 2, 2022 from https://ijp.ui.ac.ir/article_16134.html?lang=en
Bailey, D.K., 1974. Continental rifting and alkaline magmatism in the alkaline rocks, John Wiley and Sons, New York, 148 p.
Black, R. and Liegeois, J.P., 1993. Cratons, Mobile belts, Alkaline rocks sand continental lithospheric mantle: the Pan-African testimony. Journal of the Geological Society, 150(8): 89-98. Retrieved January 2, 2022 from http://www.mantleplumes.org/WebDocuments/Black1993.pdf
Chappell, B.W. and White, A.J.R., 1992. I- and S-type granites in the Lachlan Fold Belt. Earth and Environmental Science Transactions of The Royal Society of Edinburgh, v. 83(1-2), p. 1-26. https://doi.org/10.1017/S0263593300007720
Clemens, J.D., Holloway, J.R. and White, A.R., 1986. Origin of A-type granites: experimental constraints. American Mineralogist, v. 71, p. 317-324. Retrieved January 2, 2022 from http://www.minsocam.org/ammin/AM71/AM71_317.pdf
Creaser, R.A., Price, R.C. and Wormold, R.J., 1991. A-type granite revised: assessment of residual source model. Geology, v. 19(2), p. 163-166. https://doi.org/10.1130/0091-7613(1991)019<0163:ATGRAO>2.3.CO;2
Dahlquist, J., Pablo, H., Alasino, M., Eby, G.N., Galindo, C. and Casquet, C., 2010. Fault controlled Carboniferous A-type magmatism in the proto-Andean forelan (Sierras Pampeanas, Argentina), geochemical constraints and petrogenesis. Lithos, v. 115(1-4), p. 65-81. https://doi.org/10.1016/j.lithos.2009.11.006 
Davies, H.J. and Von Blank enburg, F., 1995. Slab break off: a model of lithospheric detachment and its test in the magmatism and deformation of collisional orogenes. Earth and Planetary Science Letters, v. 129(1-4), p. 85-102. https://doi.org/10.1016/0012-821X(94)00237-S
Delavari, M., Arab Asadi, F. and Mohammadi, A., 2019. Paleozoic magmatism in the southwest of Julfa (northwestern Iran): geochemical characteristics, U-Pb dating and tectonic setting. Iranian Journal of Petrology, v. 10(2), p. 99-120 (In Persian with English abstract) Retrieved January 2, 2022 from https://ijp.ui.ac.ir/article_24169.html
Eby, G.N., 1990. The A-type granitoids: a review of their occurrence and chemical characteristics and speculations on their petrogenesis. Lithos, v. 26(1-2), p. 115-134. https://doi.org/10.1016/0024-4937(90)90043-Z
Eby, G.N., 1992. Chemical subdivision of the A-type granitoids: petrogenetic and tectonic implications. Geology, v. 20(7), p. 641-644. https://doi.org/10.1130/0091-7613(1992)020<0641:CSOTAT>2.3.CO;2   
Eftekharnejad, J., Ghorashi, M., Mehr Parto, M., Arshadi, S., Zohreh Bakhsh, A., Bloorchi, M.H. and Saeedi, A., 1991. Geological map of Tabriz-Poldasht. Scale 1: 250,000. Geological Survey and Mineral Exploration of Iran (In Persian).
Fazlnia, A., 2017. Tectonomagmatic setting of the Siahbaz A-type granitoids and mafic intrusions (Northwest of Khoy). Iranian Journal of Petrology, v. 8(30), p. 31-54 (In Persian with English abstract) https://ijp.ui.ac.ir/article_21948.html
Frost, B.R., Barnes, C.G., Collins, W.J., Arculus, R.J., Ellis, D.J. and Frost, C.D., 2001. A geochemical classification for granitic rocks. Journal of Petrology, v. 42(11), p. 2033-2048. https://doi.org/10.1093/petrology/42.11.2033
Frost, C.D., Frost, B.R., Bell, J.M. and Chamberlain, K.R., 2002. The relationship between A-type granites and residual magmas from anorthosite: evidence from the northern Sherman batholith, Laramie Mountains, Wyoming, USA. Precambrian Research, v. 119(1-4), p. 45-71. https://doi.org/10.1016/S0301-9268(02)00117-1
Harker, A., 1909. The natural history of igneous rocks. Macmillan, New York, 384 p.
Harris, N.B.W., Marzouki, F.M.H. and Ali, S., 1986. The Jabel Sayid Complex Arabian Shield: geochemical constraints on the origin of peralkaline and related granites. Journal of the Geological Society, v. 143(2), p. 287-295. http://dx.doi.org/10.1144/gsjgs.143.2.0287
Henderson, P., 1982. Inorganic Geochemistry. Pergamon. Oxford, 312 p. 
King, P.L., Chappell, B.W., Allen, C.M. and White, A.J.R., 2001. Are A-type granites the high-temperature felsic granites? Evidence from fractionated granites of the Wangrah Suite. Australian Journal of Earth Sciences, v. 48(4), p. 501-514. https://doi.org/10.1046/j.1440-0952.2001.00881.x
King, P.L., White, A.J.R., Chappell, B.W. and Allen, C.M., 1997. Characterization and origin of aluminous A-type granite from the Lachlan fold belt, Southeastern Australia, Journal of petrology, v. 38(3), p. 371-391.
Konopelko, D., Biske, G., Seltmann, R. and Eklund, O., 2007. Hercynian post-collisional A-type granites of the Kokshaal Range, Southern Tien Shan, Kyrgyzstan. Lithos, v. 97(1-2), p. 140-160. https://doi.org/10.1016/j.lithos.2006.12.005
Landenberger, B. and Collins, W.J., 1996. Derivation of A-type granites from a dehydrated charnockitic lower crust. Journal of Petrology, v. 37(1), p. 145-170.
Mahood, G. and Hildreth, W., 1983. Large partition coefficients for trace elements in high-silica rhyolites. Geochemica et Cosmochemica Acta, v. 47(1), p. 11-30. https://doi.org/10.1016/0016-7037(83)90087-X
Maniar, P.D. and Piccoli, P.M., 1989. Tectonic discrimination of granitoids. Geological Society of America Bulletin, v. 101(5), p. 635-643. https://doi.org/10.1130/0016-7606(1989)101<0635:TDOG>2.3.CO;2  
McDonough, W.F. and Sun, S.S., 1995. The composition of the earth. Chemical Geology, v. 120(3-4), p. 233-253.
 https://doi.org/10.1016/0009-2541(94)00140-4
Mehri, M., Moayed, M. and Sefidgar, A., 2008. Report of magmatic epidote in Mishu granitoid massif (northwestern Iran) Data analysis and results. 16th Conference of Iranian Crystallographic and Mineralogical Association, University of Rasht. Rasht, Iran (in Persian).
Middlemost, E.A.K., 1994. Naming materials in the magma/igneous rock system. Earth Science Reviews, v. 37(3-4), p. 215-224. https://doi.org/10.1016/0012-8252(94)90029-9
Moayyed, M. and Hosseinzadeh, Q., 2011. Petrography and petrology of A-type granitoids of Eastern Mishu mountains with emphasis on their geodynamic importance, Journal of Mineralogy and Crystalography, v. 19(3), p. 529-544. (In Perian with English abstract) Retrieved January 2, 2022 from http://ijcm.ir/article-1-439-en.html
Mahamed, A., Moayyed, M. and Modjjarad, M., 2020. Garmichay S-type granites (northwestern Iran): Whole rock geochemistry, tectonic setting and generation mechanism, Iranian Journal of Petrology, v. 11(1), p. 53-72. (In Persian with English abstract). https://doi.org/10.22108/ijp.2019.118558.1146
Mufti, M.R.H., 2001. Age geochemistry and origin of peraluminous A-type granitoids of the Ablah-Shuwas pluton, Ablah graben, Arabian Shield. Acta Mineralogica- Petrographica, v. 42(1), p. 5-20. Retrieved January 2, 2022 from http://acta.bibl.u-szeged.hu/39423/1/mineralogica_042.pdf#page=7
Nabavi, M.H., 1979. Introduction to Geology of Iran. Geological Survey of Iran, Tehran, 109 p (In Persian).
Patino Douce, A.E., 1998. What do experiments tell us about the relative contributions of crust and mantle to the origin of granitic magmas? In: A. Castro. C. Fernández. and J.L. Vigneresse (Editors), Understanding Granites: Integrating New and Classical Techniques, Journal of the Geological Society, Special Publications, v. 168(1), p. 55-75.
Petro, W.L., Vogel, T.A. and Willboard, J.T., 1979. Major elements chemistry of plutonic rock suites from compressional and extensional plate boundaries, Chemistry Geology, v. 26(3-4), https://doi.org/10.1016/0009-2541(79)90047-0
Schandle, E.S. and Groton, M.P., 2002. Application of high field strength elements to discriminate tectonic settings in VMS environments, Economic Geology, v. 97(3), p. 629-642. http://dx.doi.org/10.2113/ gsecongeo. 97.3.629
Shahzeidi, M., Moayyed, M., Arai, S., Pirnia, T. and Ahmadian, J., 2012. Geology and geochemistry of Mishu S-type granitoid NW Iran, Iranian Journal of Petrology, v. 3(11), p. 111-126 (In Persian with English abstract) Retrieved January 2, 2022 from https://ijp.ui.ac.ir/article_16107.html?lang=en
Shirmohammadi, M., Sepahi Gerow, A., Maanijou, M. and Tourkian, A., 2020. Geochemistry and petrogenesis of south Qorveh A-type granitoids (northwest of Sanandaj- Sirjan zone): An evidence for active continental margin tensional tectonic, Iranian Journal of Petrology, v. 11(3), p. 85-110 (In Persian with English abstract) Retrieved January 2, 2022 from https://ijp.ui.ac.ir/article_25571.html?lang=en
Streckeisen, A., 1974. Classification and Nomenclature of Plutonic Rocks. Geologische Rundschau, v. 63(3), p. 773-786. https://doi.org/10.1007/BF01820841
Stocklin, J., 1978. Structural history and tectonics of Iran: A review. American Association of Petroleum Geologists Bulletin, v. 52(7), p. 1229-1258. https://doi.org/10.1306/5D25C4A5-16C1-11D78645000102C1865D
Sun, S.S. and McDonough, W.F., 1989. Chemical and Isotopic Systematics of Oceanic Basalts: Implications for Mantle Composition and Processes. In: A.D. Saunders, M.J. Norry (Editors), Magmatism in the Ocean Basins. Geological Society, London, Special Publications, v. 42(1), p. 313-345. http://dx.doi.org/10.1144/GSL.SP.1989.042.01.19
Sylvester, P.J., 1989. Post-Collisional Alkaline Granites, the Journal of Geology, v. 97(3), p. 261-280. Retrieved January 2, 2022 from http://www.jstor.org/stable/30068745
Taylor, R.P., Strong, D.F. and Fryer, B.J., 1981. Volatile control of contrasting trace element distributions in peralkaline granitic and volcanic rock. Contribution to Mineralogy and Petrology, v. 77(4), p. 267-271.
 https://doi.org/10.1007/BF00373542
Torkian, A. and Niknazar, A., 2020. Geochemistry and tectonic setting of the A-type granitoid in Sanandaj-Sirjan zone: Shirvaneh, NE- Sonqor (Kermanshah Province), Iranian Journal of Petrology, (In Persian with English abstract), doi.org/10.22108/ijp.2020.123999.1191
Wedepohl, K.H., 1995. The composition of continental crust. Geochemica et Cosmochimica Acta, v. 59(7), p. 1217-1239. https://doi.org/10.1016/0016-7037(95)00038-2