TY - JOUR T1 - Mineralogical paragenesis variations of northwest Sabzevar granulites during metamorphic evolutions TT - تغییرات پاراژنزهای کانی‌شناسی گرانولیت‌های شمال غرب سبزوار در طی تحولات دگرگونی JF - ijcmir JO - ijcmir VL - 18 IS - 4 UR - http://ijcm.ir/article-1-488-en.html Y1 - 2011 SP - 531 EP - 544 KW - Sabzevar KW - granulite KW - mineralogical paragenesis KW - metamorphic evolution. N2 - There are metabasite exposures inside ophiolitic belt of northwest Sabzevar that metamorphosed under high pressure granulite facies. On the basis of mineralogical paragenesis, reactional textures between different mineralogical assemblages, textural and mineralogical relations between inclusion and porphyroblast and stability fields of different mineralogical assemblages, five stages of evolution of metamorphism is distinguished. These stages consist of prograde metamorphic stage (M1), peak metamorphic stage (M2), garnet kelyphitisation as the formation of Pl+Am symplectite and corona (M3), partial or quite replacement of garnet by Am+Chl+Ep assemblage (M4) and the occurrence of Prh-Zl veins. The thermobarometric data of these stages represent a clock-wise P-T path. This path is consistent with the collision of the Iranian micro-continent with the Alborz block and later erosion and uplifting. M3 ER -