5:15 PM - 6:45 PM
[SGD02-P08] Seismic potential of Main Recent Fault in Iran: Interseismic fault locking, slip rate and earthquake recurrence interval
Keywords:Seismic potential , InSAR, Main Recent Fault, Fault locking
The Main Recent Fault (MRF) is an important geological boundary fault that accommodates the oblique convergence motion between the Arabian and Eurasian plates. Several large earthquakes including the 1909 Mb 7.4, the 1958-1963 sequence of three events with magnitude larger than Mw 6.0, and the 2006 Mw 6.1 earthquake had partly ruptured the central and southeast segments of MRF. However, no large earthquake occurred in the northwest segment in the past hundred years. In this study, the interseismic surface deformation is firstly mapped from the Synthetic Aperture Radar (SAR) images acquired by the Sentinel-1 satellite. Then, the fault slip rate, coupling ratio and locking depth are estimated along the fault based on the measured interseismic surface deformation. The results show that the interseismic fault motion is controlled by a dominant dextral strike-slip with slightly varies from ~4.0 mm/yr to ~6.3 mm/yr along the MRF. Furthermore, it is also found a non-negligible extensional motion with average rate of ~4.7 mm/yr in the northwest segment of MRF. In addition, seven sub-segments could be divided based on the fault coupling distribution and historical earthquakes in the area of interest. According to the potential seismic magnitude and estimated recurrence interval, it is found that several sub-segments are approaching the end of their interseismic recurrence interval. Meanwhile, one sub-segment (SF-6) may be in the early stage of a new recurrence period due to the recent several large earthquakes and a long recurrence interval.