University of Isfahan Petrological Journal 2228-5210 11 1 2020 04 20 Garmichay S-type granites (northwestern Iran): Whole rock geochemistry, tectonic setting and generation mechanism Garmichay S-type granites (northwestern Iran): Whole rock geochemistry, tectonic setting and generation mechanism 53 72 24374 10.22108/ijp.2019.118558.1146 FA Amir Mahamed Department of Geology, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran Mohsen Moayyed تبریز - دانشگاه تبریز - دانشکده علوم طبیعی - گروه علوم زمین Monir Modjjarad Geology Department, Faculty of Geology, University of Urmia, Urmia, Iran. Journal Article 2019 08 02 The Garmichay area in the north of Mianeh, NW Iran, features schists, amphibolites, calc-silicates, marbles and granitoids. Granitoids are of S- and A-type nature. Partial melting is the main generation mechanism, the progenitor is a pelite enriched in muscovite and the major melting reaction is muscovite dehydration. The ASI for the S-type granite varies between 1.12-1.5 indicating peraluminous character and crustal origin. Both granitic types are enriched in LREE in relation to HREE with negative Eu anomalies. La<sub>n</sub>/Yb<sub>n </sub>ranges are 1.49-3.09 and 1.34-1.99 for the S-type and the A-type granites, respectively. Moreover, La<sub>n</sub>/Gd<sub>n</sub> varies between 2.45 and 5 for the S-type granite and 1.53 and 1.75 for the A-type granite. The S-type granite has been generated in a collisional zone during Assyntic Orogeny.The A-type granite, however, is formed in a within-plate environment.The A-type granite belongs to A1 subtype formed in a continental rifting setting. The crystallization temperatures for the S-type and the A-type granites vary from 650 to 750 ºC and 800 to 850 ºC،respectively.   The Garmichay area in the north of Mianeh, NW Iran, features schists, amphibolites, calc-silicates, marbles and granitoids. Granitoids are of S- and A-type nature. Partial melting is the main generation mechanism, the progenitor is a pelite enriched in muscovite and the major melting reaction is muscovite dehydration. The ASI for the S-type granite varies between 1.12-1.5 indicating peraluminous character and crustal origin. Both granitic types are enriched in LREE in relation to HREE with negative Eu anomalies. La<sub>n</sub>/Yb<sub>n </sub>ranges are 1.49-3.09 and 1.34-1.99 for the S-type and the A-type granites, respectively. Moreover, La<sub>n</sub>/Gd<sub>n</sub> varies between 2.45 and 5 for the S-type granite and 1.53 and 1.75 for the A-type granite. The S-type granite has been generated in a collisional zone during Assyntic Orogeny.The A-type granite, however, is formed in a within-plate environment.The A-type granite belongs to A1 subtype formed in a continental rifting setting. The crystallization temperatures for the S-type and the A-type granites vary from 650 to 750 ºC and 800 to 850 ºC،respectively.   Granite S-type A-type collision zone Continental rift Garmichay Mianeh https://ijp.ui.ac.ir/article_24374_8958c03ff190cb6788a7da591fb70514.pdf