Kinetic Evaluation of Bafgh-Baghin Fault System Based on Morphotectonic Evidences

The Bafq-Baghin fault system is one of the major faults in Central Iran and parallel to the Kuhbnan fault in the northeast and the Rafsanjan fault in the southwest. This fault system, under the influence of the stress, is the maximum that results from the convergence of the Arabian plate towards Iran plate has a right-strike with a compression component.  The study area is located in central Iran and its southeastern part. In the last division of central Iran, this region is located in the Poshtbdam.

 Using satellite images and related software and integration with field data, fault system components were identified and mapped. Morphotectonic relationships and formulas were used to analyze the tectonic morphology of the region. Active strike-slip faults, especially those on the mountain front, usually appear as separate sections. By processing satellite images of the region and based on the study of building parameters, geometric condition, tracking along the fault system, examining changes along the direction, motion and branching sub-structures along the system, it was determined that the Bafgh-Baghin fault-slip fault system is like most active faults. It is formed in separate pieces.

  By studies performed during the system, 60 fault pieces were identified. Bafgh-Baghin fault sections were examined for tectonic morphology, which is evidence that the Bafgh-Baghin fault system is adjacent. In the direction of fault sections, fault precipices have been formed, which in some cases, several-meter precipices were observed. Folds with strike-slip faults are usually stepped and sloping to the main cutting direction. The term en echelon refers to the arrangement of buildings in a linear zone, so that the folds or faults are parallel to each other and have the same tendency towards the direction of the linear zone. The naming of en echelon folds is based on the displacement of the right-slip zones that create them, so that right-slip faults create right-handed folds and left-handed right-slip faults create left-handed folds. Due to the right-slip activity of fault sections, some folds in the mountains have become right-stepped. Large amounts of Vf are associated with low uplift rates, ie low tectonic activity, in which rivers have relatively wide bottoms. Low Vf values refer to deep valleys in which rivers actively dig valleys and are usually associated with active tectonics and uplift.Mountainous fronts associated with active tectonics have sinusoids (Smf) between 1.6 and 1. Low-activity mountain fronts have sinusoids between 3 and 1.6, and inactive mountain fronts have sinusoids of about 3 to values greater than 5 because of high erosion and inactive tectonics. The low values of mountain front page maze (Smf) and the ratio of valley width to valley depth (Vf) calculated in the direction of fault plots indicate fault and tectonic faults of the region. Wherever the strike-slip fault becomes stepped or bends, due to the movement of the fault in these areas, it either suffers from divergence and tensile forces that lead to elongation and pull-apart basin, or suffers from convergence forces that result. They create compression and pressure in the basin. In the pull-apart basin, normal faults and subsidence are created and it is a suitable place for sediment accumulation. In the compressive basin, compressive ridges and inverse faults are formed. Due to the fact that Bafgh-Baghin fault sections have a strike-slip mechanism, where the pieces are placed relative to each other, pull-apart basins and compressive basins are formed between these fault sections. With the strike-slip activity of the fault sections, pull-apart basins have been created between some fault sections that are staggered relative to each other. In one of the pull-apart basins of the region, a fertile village called Khanaman has been formed on the southwestern front of the Bafgh-Baghin fault system.