Seismic Hazard Assessment of the City of Khoy and Its Vicinity, NW of Iran

Abstract

Analyses have been carried out considering the occurred earthquakes, geologic and seismotectonic conditions of the region covering a radius of 100 Km keeping Khoy as the center. The major seismic sources are small and large faults identified in the study area mostly directed in NW-SE. The MCE and PGA were measured based on both DSHA and PSHA approaches. The results of DSHA show that the MCE and PGA evaluated values are 6.8 Richter and 0.31g, which might be created by Chahar-Sotoon and Askar-Abad faults, respectively. The results of PSHA show that the MCE evaluated value is 6.1 Richter for a 0.64 probability in a 50- year period. Seismic hazard parameters have been evaluated considering the available earthquake data using Gutenberg-Richter relationship method. The ‘a' and ‘b' parameters were estimated 6.03 and 0.94, respectively. For earthquakes with magnitudes equal or greater than 6.1 Richter, the values of returning period (TR) and annual occurrence probability (PT) were obtained 112 and 0.009, respectively. The results obtained from two mentioned methods are matched to each other.