Investigation of Microstructural Evidence of Partial Melting and Mineral Chemistry in Contact Metamorphic Rocks of the Misho Aureole, NW Iran"

Document Type : Original Article

Author

Department of Earth Sciences, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran

Abstract

The Ediacaran Misho Granitoid Pluton and its Contact Metamorphic Aureole are located southwest of Marand in northwest Iran.The Misho granitoid complex, a horseshoe-shaped outcrop extending around 50 km², is of Cadomian age.

.The occurrence of peritectic minerals such as cordierite and garnet in Misho migmatites' leucosomes indicates that partial melting reactions were important in their genesis.Anhedral quartz, zoned plagioclase, and myrmekitic textures are examples of microstructures formed by direct crystallization from a melt. In contrast, some K-feldspars containing biotite and quartz inclusions are restitic phases.The chemistry of biotite indicates two unique generations: eastonite and siderophyllite, which indicate different physicochemical conditions during prograde metamorphism and anatexis.Garnet-biotite geothermometry reveals average temperatures of ~565°C for the first generation and ~632°C for the second, indicating a gradual temperature increase due to partial melting in the

Keywords


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