Finite strain and deformation flow geometry in the Sanandaj-Sirjan HP-LT metamorphic belt, Iran

For the first time the changes of kinematic and strain parameters along the Sanandaj Sirjan HP-LT metamorphic belt were studied in this research. Also a new method for determination of 3D strain with application of Mohr diagram using the geometry of no finite longitudinal strain and the RXZ strain ratio was proposed. The study area is located in Bahrame Gure area, 250 km east from Shiraz in the southwestern Iran. Geologically the study area is part of Sanandaj-Sirjan HP-LT metamorphic belt. Finite strain and kinematic vorticity analyses of deformation were carried out in this area. For these purposes the Bahrame Gur area was divided into three homogeneous sub domains (NW, central and SE). Quartz grains, pebbles of deformed conglomerates and rotated porphyroclasts were applied as strain markers respectively in the NW, central and SE domains of the study area. The kinematic vorticity analyses estimated Wm values for NW, central and ES domains (0.43±0.04