An Evaluation of Earthquake Hazard Parameters in and around Ağrı

Year 2015, Volume: 1 Issue: 1, 1 - 9, 20.05.2015

Yusuf Bayrak , Ayşe Nur Atmış Hiwa Mohammadı Erdem Bayrak Şeyda Yılmaz Tuğba Türker

Abstract

The earthquake hazard parameters of  a and b of Gutenberg-Richter relationships, return periods, expected maximum magnitudes in the next 100 years and probabilities for the earthquakes for certain magnitude values are computed using the earthquakes occurred between 1900 and 2014 years in and around Ağrı.  The relation of LogN=4.73-0.68M is calculated for the studied area.  The mapping of b values show that the regions in the east and southeast of Ağrı, east of Horasan and around Patnos where low b values are computed have high stress levels and capacity to occur large earthquakes in the future. It is found that earthquakes larger than 5.5 may be occurred in the regions where b values lower than 0.8 have been observed in the next 100 years. The return periods for magnitudes between 5.0 and 7.3 are estimated between 5 and 176 years in the studied area.  The probabilities of an earthquake with M=6.0, 6.5 and 7.0 in the next 100 years are computed 99%, 86% and 59%, respectively. The largest earthquake occurred in the studied area is 7.3 and its probability to occur is 43% in the next 100 years.  The faults around Ağrı are seismically active and have potential to an earthquake larger than 6.0. Since the sediment basin of Ağrı is very young and alluvial layer is tick, there is very high hazard on the buildings and human’s life in Ağrı. 

Keywords

b values, return period, expexted maxium, magnitude, Ağrı, Eastern Anatolia

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