Evaluating the Potential of Occurrence of Earthquake in City of Tabriz

According to the seismotectonic study, Tabriz region and its surrounding have been in an area with high seismic risk. Main and Seismic faults such as The North Tabriz Fault, Tasuj, Shabestar, South Misho, North Misho, etc… are placed at a little distance from Tabriz. Since the little distance of thses faults and some records of earthquakes along their length in past, occurrence of a destructive earthquake along each of those faults in feature can exert shakes with moderate to high horizontal PGA at the site of Tabriz city. The North Tabriz Fault that placed in the vicinity of Tabriz has expected the greatest threat of earthquakes for this city so that this fault in 50 and 100yr periods, with 64% probability of exceedance has the potential of creating an earthquake with horizontal peak ground acceleration (PGA) 0/23g and 0/18g in Tabriz city. Attention to average horizontal PGA maps drawing in this paper, Tabriz city in 50, 100 and 475yr periods with 10% probability of exceedance has placed in area with very high risk of earthquake and in 100yr period with 64% probability of exceedance has placed in area with high risk of earthquake. Based on Gutenberg- Richter relation and seismicity of Tabriz city, recurrence periods of earthquake with Ms=7 and Ms= 7/4 in this city are 291 and 558 years.