Dextral transpressional deformation along the Chalderan shear zone, NW Iran


1 Department of Geology, Science and Research Branch, Islamic Azad University, Tehran, Iran

2 Department of Geology, Khoy Branch, Islamic Azad University, Khoy, Iran


Chalderan shear zone (SCZ) is located 270 km north of Urmia and 868 km west of Tehran. The structural and microstructural studies show two groups of the main structure in this area. The first group includes structures related to inclined shear movements, which include: asymmetric mantled porphyroclasts, fabric C and S and mineral fish structures, and the second group is related to thrust movements that occur in this area. The inclined shear movements are created by inclined transpressional strike slip component and thrust movements are created by inclined transpressional component. There is kinematic evidence of the function of shear and transpressional stresses in this region, all of which indicate the function of a shear zone with a moderate slope mylonitic foliation to the northeast and stretching lineation to the northeast with inclined strike slip mechanism with inverted component in this region. In the study area, we proposed inclined dextral transpression strike slip model.The fact that the structures and microstructures indicating reverse shear and inclined strike slip in this zone are observed with each other indicates the occurrence of partitioning in this shear zone. This indicates that tectonic forces inclined to Chalderan shear zone deformation zone occurred due to transpressional tectonics between Arabian plate and Central Iran block in northwestern Iran.


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