Application rare earth elements geochemical for comparing migmatites, leucosome and granites of Boroujerd area: Exploratory view


1 Department of Geology, Faculty of Sciences, Lorestan University, Iran

2 Department of Geology, Faculty of Sciences, Shahid Chamran University of Ahvaz, Iran


Boroujerd Metamorphic Complex is consist of regional and contact metamorphisms. The intrusion of middle Jurassic Boroujerd granitoid complex in the metapelite rocks has caused the formation of pelitic hornfels, and partial melting derived migmatites. Leucosum of migmatites composed mainly of plagioclase, quartz, feldspar, biotite and muscovite minerals, having myrmekite, pertite and graphic textures. Leucosum of migmatite is peraluminous and has high amounts of K2O as well as low values of MgO, Fe2O3, and TiO2. According to petrographic studies, the composition of leucosome in the Boroujerd migmatites is granite. Also, according to the study of petrography and chemical analysis, it is determined that leucosome of Boroujerd migmatites belong to S ـ  type granites that are different from the adjacent granite mass. The chondrite-normalized REE pattern of leucosome has a negative slope and positive Eu anomaly. The difference in the REE pattern of granites and leucosome of migmatite indicate that granites do not have any relation with leucosomes and partial melting of metapelite rocks do not form them. The study of Boroujerd migmatites is important from the exploratory point of view, Due to the formation of spinel and corundum minerals in these migmatites.


Main Subjects

حیدریان منش. ع.، طهماسبی.ز.، احمدی خلجی.ا.، 1395، شیمی کانی و دما ـ فشارسنجی سنگ­های میگماتیتی منطقه بروجرد (شمال پهنه سنندج ـ  سیرجان)، مجله پترولوژی اصفهان، شماره 25، ص 117 ـ 138.
ساکی. ع.، 1391، دلایل پایداری آندالوزیت در زون‌های سیلیمانیت و اسپینل کردیریت موجود در میگماتیت­های هاله مجاورتی الوند، همدان، مجله زمین‌شناسی کاربردی پیشرفته، جلد 1، شماره4.
Ahmadi ـ Khalaji. A., Esmaeily. D., Valizadeh. M.V., Rahimpour ـ Bonab. H., 2007, Petrology and Geochemistry of the Granitoid Complex of Boroujerd, Sansandaj ـ Sirjan Zone, Western Iran, Journal of Asian Earth Sciences, No:29, p:859 ـ 877.
Baharifar. A.K., Ghafari. M., 2010, First report of Corundum occurrence and granulite grade metamorphism in migmatitic rocks of SE ـ Broujerd, 4th National Geological Conference of Payam Noor University, Mashhad, Iran (in Persian).
Barbay. P., Brouand. M., Le Fort. P., Pecher. A., 1996, Granit ـ migmatite genetic link: The example of the Manaslu granite and Tibetan Slab migmatites in central Nepal, Lithos, No: 38, p: 63 ـ 77.
Boynton. W.V., 1984, Cosmochemistry of the rare earth elements, meteorite studies. In: Rare earth element geochemistry, Henderson, P. (Editors), Elsevier Sci. Publ. co., Amsterdam, p: 63 ـ 114.
Brown. M., 1994, The generation, segregation, ascent and emplacement of granite magma: the migmatite ـ to ـ crustally ـ derived granite connection in thickened orogens, Earth Science Review, No: 36, p: 83–130.
Cesare, B., Salvioli Mariani, E. & Venturelli, G., 1997- Crustal anatexis and melt extraction in the restitic xenoliths at El Hoyazo -SE Spain. Mineralogical Magazine, 61: 15-27.
Chappell. B.W., White. A.J.R., 1992, I and S ـ type granites in the Lachlan Fold Belt, Trans. R. Soc. Edinb. Earth Sci, No: 83, p: 1–26.
Clark. D. B., 1992, Granitoid Rocks, Chapman and Hall, London, 223 pp.
Corona ـ Chávez. P., Poli. S., Bigioggero. B., 2006, Syn ـ deformational migmatites and magmatic ـ arc metamorphism in the Xolapa Complex, southern Mexico, Journal of metamorphic Geology, No: 24, p: 169 ـ 191.
Droop. G.T.R., Moazzen. M., 2007, Contact metamorphism and partial melting of Dalradian pelites and semipelites in the southern sector of the Etive aureole, Scottish Journal of Geol, Vol: 43, No: 2, p: 155 ـ 179.
Fitzsimons. I.C.W., 1996, Metapelitic migmatites from Brattstr and Bluffs East Antarctica metamorphism, Melting Exhumation of the mid crust, J. Petrol, No: 37, p: 395 ـ 414.
Harris. N.B.W., Pearce. J.A., Tindle. A.G., 1986, Geochemical characteristics of collision ـ zone magmatism. In: Coward. M.P., Ries. A.C., (Eds.) Collision Tectonics, Journal of Geological Society of London, No: 19, p: 67–81.
Kriegsman. L.M., 2001, Partial melting, partial melt extraction and partial back reaction in anatectic migmatites, Lithos, No: 56, p: 75 ـ 96.
Krietz. R., 1983, Symbols for rock ـ forming minerals, American Mineralogist, No: 68, p: 277–279.
Lancaster. J., Fu. B., Page. F.Z., Kita. N.T., Bickford. M. E., Hill. B.M., Mclelland. J.M., Valley. J.W., 2009, Genesis of metapelitic migmatites in the Adirondack Mountains, Journal of Metamorphic Geology, No : 27, p: 41 ـ 54.
Maniar. P.D., Piccoli. P.M., 1989, Tectonic discrimination of granitoids, Geological Society of America. Bulletin, No: 101, p: 635–643.
Masoudi. f., 1997, Contact metamorphism and pegmatite development in the region S.W of Arak, Iran, Ph.D. thesis, University of Leed, England, 321p.
Masoudi. F., Yardley. B.W.D., Cliff. R.A., 2002, Rb ـ Sr geochronology of pegmatites, plutonic rocks and a hornfels in the region southwest of Arak, Iran, Islamic Republic of Iran, Journal of Sciences, No:13, p:249 ـ 254.
Mohajjel, M., Fergusson, C.L. and Sahandi M.R. 2003, Cretaceous-Tertiary convergence and continental collision, Sanandaj-Sirjan zone, Western Iran. Journal of Asian Earth Sciences 21: 397-412.
Mohajjel. M., 1997, Structure and tectonic evolution of Paleozoic ـ Mesozoic rocks, Sanandaj ـ Sirjan zone, Western Iran, Ph.D. Thesis, University of Wollongong, Australia.
Neogi. S., Dasgupta. S., Fukuoka. M., 1998, High ـ T polymetamorphism, Dehydration melting and generation of migmatites and granites in the higher Himalayan crystalline complex Sikkim India, J. Petrol, No: 39, p: 61 ـ 99.
Patiño Douce. A.E., 1999, What do experiments tell us about the relative contributions of crust and mantle to the origins of granitic magmas? In: Castro A., Fernandez C., Vigneresse J.L. (Eds.), Understanding granites: integrating new and classical techniques, Geological Society of London, No: 168, p: 55–75.
Pattison. D.R.M., Harte. B., 1988, Evolution of structurally contrasting anatectic migmatites in the 3 ـ kbar Ballachulish aureole, Scotland, Journal of Metamorphic Geology, No:6, p:475 ـ 494.
Pitcher W.S. 1993: The nature and origin of granite. Chapman & Hall. New York.
Rickwood. P.C., 1989, Boundary lines within petrologic diagrams which use of major and minor elements, Lithos, No: 22, p: 247–263.
Roberts M.P., Clemens J.D. 1993: Origin of high-potassium, calc-alkaline, I-type granitoids. Geol. 21: 825–828.
Sawyer. E. W., 1998, Formation and evolution of granite magmas during crustal Reworking the significance of diatexites, Journal of Petrology, No: 39, p: 1147 ـ 67.
Searele. M.P., Fryer. B.J., 1986, Garnet ـ tourmaline ـ and muscovite ـ bearing leucogranites, gneisses and migmatites of the higher Himalayas from Zanska, Kulu, Lahoul and Kashmir. In: Coward. M.P., Ries. A.C., (Eds.), Collision Tectonics Geological Society of London, No: 19, p: 185–202.
Shand. S.J., 1927, Eruptive Rocks, D. Van Nostrand Company, New York.
Stoklin. J., 1968, Structural history and tectonics of Iran, A review American Association Petroleum Geologists, No: 52, p: 1229 ـ 1258.
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, Geological Society London Special Publications, pp: 313–345.
Thompson. A.B., 1982, Magmatism of the Bristish Tertiary volcanic Province, Scott, Journal of Geology, No: 18, p: 50–107.
Wyllie. P. J., 1993, Experimental and thermal constraints on the deep ـ seated parent age of some granitoid magmas in subduction zones. In: M. P. Atherton and C. D. Grbble (eds). Migmatites melting and metamorphism, Shiva, Natwich.