Estimation of Suran Fault Activity in the East of Iranshahr with Morphotectonic and Seismotectonic Evidence

The Suran region is located in the Nehbandan-Khash tectonic zone and its faults are part of the Makran active fault in southeastern Iran. The Suran fault, southwest of the Saravan fault, is inferred and parallel to the Saravan fault, which is located on the border of Baluchestan. Geomorphologic evidence such as drainage basin asymmetry, BS index, hypsometric integrals, and drainage patterns indicate high neo-tectonic activity in the region. The main faults of the region include active Quaternary faults and non-Quaternary faults, which are mostly of secondary and inactive type. Old faults in the area, which in some places are related to active Quaternary faults, are likely to be active. According to the rose diagram, the predominant trend of Quaternary and non-Quaternary faults and fractures in the region is in the direction of N100. According to the fracture intensity map drawn in GIS, and considering that in areas where the length of the fault and fracture is greater, the amount of reactivation on it increases, the places where the faults can reactivate were identified. Due to the seismicity formula obtained from the seismic data of the region and the high b-value, the crust can withstand the accumulation of stress, so the stress will be discharged at long intervals, but with more strain from the faults in the region. Therefore, a large earthquake will not occur in the area soon. Calculation of the acceleration of gravity due to active Quaternary faults to this region shows that the Suran fault with an approximate length of 52 km, if active with at least 40% of its length at a distance of 3.5 km from the center of the area, will cause the maximum horizontal acceleration the city of Suran