Spatial Prediction of Large Earthquakes in Iran Using Coulomb Failure Criteria

It is important to answer the question of how occurrence of an earthquake can trigger another? An earthquake happening is accompanied with fault or fracture in the earth's crust. For this purpose, it is necessary to examine failure criteria in elastic environment of earth’s crust that is Coulomb failure criteria. Coulomb stress change analysis has been applied in numerous seismically active regionsof the globe. These studies demonstrate categorically that the locations and rates of futureearthquakes are affected by the static stress changes due to nearby historicalearthquakes. In this study, Coulomb stress interaction between the fault systems in Iran has been studied. Parameters of earthquakes with magnitude above 6 that have occurred in this region from 1900 to 2001 have been collected from various sources in order to calculate Coulomb stress. The results indicate that more than 80% of the occurred earthquakes from 2001 to 2013 in the region of increased Coulomb stress caused by the past 100 years earthquakes have the rate of 0.01 to 5. Also, the calculation of Coulomb stress changes on the strike-slip, stretching and normal fault pages with optimized geometry shows that the faults which have the same direction as optimized geometry, are prone to rupture and cause earthquake as the results of increased Coulomb stress caused by earthquake and are considered as areas of high risk for future earthquakes.