Shear structures study in Along the Hesar-Kuchok fault zone, southwest Khoy


1 Hassan Haji Hosseinlou Ph.D, Assistant Professor Tectonics Department of Geology, Khoy Branch, Islamic Azad University, Khoy, Iran

2 Department of geology, Khoy branch, Islamic Azad University, Khoy, Iran,


The Hesar-Kuchok area is located between 38◦ 35\ 34\\ - 38◦30/ north and 44◦ 35\ 34\\ - 34◦30/ east in northwestern Iran, approximately 45 km south west of Khoy. Hesar-Kuchuk area is located in a part of Khoy melange ophiolite. There are many shear structures in this area. According to the information obtained from the studies of shear structures along the Hesar-Kouchok fault zone (HKFZ which the structures were both high temperature and low temperature, so that the most important shear sense markers high temperatures include S-C shear bands, mineral fish, elongated feldspar bands, -type mantle porphyroclasts, sigmoid and asymmetric boudins. The most important shear sense markers in low grade shear zones are -type mantle porphyroclasts, undulose extinction at quartz. The model as proposed in research area as dextral transpression tectonic regime. The presence shear sense indicators such as -type mantle porphyroclasts, S-C fabrics and mineral fish indicate strong strike-slip movements in the region. Also, the observation of the HKFZ indicates thrusting in this area.


Main Subjects

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