Deformation microstructures in mylonitic leucogranite in the west of Yazd

Authors

1 Department of Geology.Faculty of Science.Yazd university. Yazd.Iran

2 Faculty of natural resources and earth sciences, Shahrekord University, Sharekord, Iran

Abstract

The mylonitic leucogranite is exposed in the west of Yazd on the edge of Shirkoh granite. Based on the structural division of Iran, the region is situated in the Yazd block, Central Iran. The petrographical studies show the rocks mostly contain quartz, alkali feldspar, and plagioclase. Occasionally, muscovite with biotite, tourmaline, rutile, allanite, zircon, titanite, and epidote are seen in some samples. Deformation and metasomatism evidence is observed as recrystallization along with grain boundary migration, microstructures of grain boundary migration, undulate extinction, deformation twinning, folding and bending in mica, intergrowth of crystals (such as graphic texture), co-oriented muscovitization of biotite and co-oriented albitization, perthitic and mylonitic texture in the rocks. According to mentioned evidence, leucogranites have been affected by post-magmatism events such as metamorphism, deformation, and in the temperature range of 250 ° to 700 °C and during these events, they have undergone alteration and metasomatism with the presence of fluids.

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