TY - JOUR JF - jsci JO - VL - 16 IS - 42 PY - 2015 Y1 - 2015/5/01 TI - Mica chemistry and metamorphism in garnet-micaschists of Haji-Qara high, North of Golpayegan TT - شیمی میکاها و رخداد دگرگونی در گارنت میکاشیست‌های ارتفاعات حاجی قارا،‌ شمال گلپایگان N2 - Garnet-micaschists from Haji Qara high, north of Golpayegan, are part of the metamorphic rocks of the Sanandaj-Sirjan Zone (SSZ). Lepidoporphyroblastic and porphyropoikiloblastic are the main textures and the mineral assemblages consist dominantly of Fe-biotite, muscovite and ferriphengite, metamorphic Fe-Mg chlorites (I-type and IIb), garnet and quartz. Staurolite, andalusite, plagioclase carbon, Fe-oxides and tourmaline are present as accessories. Petrographic evidences as well as mica chemistry along with other paragenesis and thermometric estimations indicate a path change from amphibolites facies to lower pressure and higher temperature gradient suggesting the presence of a local pluton which led to garnet porphyroblast, biotite and muscovite (overprinted in different orientation) and andalusite crystallization. The occurrence of chlorite, ferriphengite and Fe-oxides demonstrate a retrograde metamorphism during uplift and decompressional cooling path in the area. SP - 71 EP - 88 AU - mirlohi, Akramosadat AU - Khalili, Mahmoud AU - Tabatabaei-manesh, Seyed Mohsen AU - Massonne, Hans-Joachim AD - Department of Geology, university of Isfahan KW - Mica KW - Metamorphism KW - Metaplite KW - Golpayegan KW - Sanandaj- Sirjan Zone (SSZ) UR - http://jsci.khu.ac.ir/article-1-1842-en.html ER -