Siesmotectonic studies and siesmic hazard evaluation of Khersan 1-5 dam site

Subject Areas :

Mohsen Poorkermani ¹ (استاد دانشگاه آزاد اسلامی واحد تهران شمال)
Ahmad Adib ² (استادیار دانشگاه آزاد اسلامی واحد تهران جنوب)
Nasser Ahmadi Comijany ³ (کارشناس ارشد زمین شناسی مهندسین مشاور مشانیر)
Azam Labbaf Khaniki ⁴ (کارشناس ارشد زمین شناسی تکتونیک دانشگاه ازاد اسلامی واحد تهران شمال)

Received: 2016-09-07 Accepted : 2016-09-07 Published : 2011-09-23

Keywords: Earthquake, hazard analysis, maximum credible level, Khersan 1-5 dam,

Abstract :

The region of Khersan 1-5 dam is in Chaharmahal-Bakhtiari province. It is located 45 km west of Lordegan city.The reported earthquakes in this region are low depth type and have a focal depth less than 15 km. They alsohave no surface failure. The seismic hazard analysis illustrates the nature of seismicity of the site and isevaluated according to dispersion , fault type, morphology of faults, and past earthquakes data. Here, usingtectonic maps of the site, arial and satellites photos , and the seismic data of the site, it have been tried that theseismicity of the site to be determined. Bazoft and Massan faults with 45 and 36 km length, are the nearest faultsto the site. When they become active, they can provide an earth quake as big as M=7.0 and 6.9 richters,respectively. Bazoft and Massan faults have the ability to provide the MCLs as big as 0.269g, 0.222g,respectively.According to probabilistic seismic hazard analysis in the site, for return periods of 150, 475 and 2000 years, andaccording to Bender & Perkins (1987) method, and using (Seisrisk III) software, accelerations equal to 0.261g,0.291g, and 0.310g, for the center of zone, are calculated respectively.