Deformation condition determination and strain analysis: Application of microstructural and microthermometry study of the Zamanabad Shear Zone (East of Iran)

Microstructural analysis and microthermometry are useful methods for determining the deformation evolution. To address this issue, rheological behavior of quartz, feldspar and calcite in veins and host rocks during deformation, are presented in the mylonite zone of the dextral reverse Zamanabad Shear Zone (ZSZ), in northern part of Sistan Suture Zone (SSZ), in east of Iran. Microstructure evidences revealed two evolution stages of high and low temperature deformation. Quartz microstructures in the ZSZ show abundant evidences for early high-temperature plastic deformation (e.g. Bulging recrystallization (BLG)) which are as microstructures with SW directed ductile shearing in the central parts of the ZSZ. This shear zone shows progressively decreasing strain away from the central of shear zone toward the wall. High-temperature microstructures are overprinted partly or completely during shearing by the later low-temperature deformation (e.g. Pressure solution, fractures, veinlets). Microstructural observations of veins (quartz and calcite) confirms the results of microstructures in the host rock, as quartz veins occurred from peak metamorphic conditions (