Seismic Source Modeling in the Shores of Western Makran

Abstract

Makran is an active subduction zone with a lower activity rate in comparison with other similar subduction zones. In the extent of Makran seismotectonic province, from coastline up to 70 Km distance onshore, the earthquakes are shallow whilst further inland, focal depths of the earthquakes are deeper. Considering the low seismic activity rate, lack of adequate and reliable seismic data and uncertainty about earthquake hazard contribution ratio of subduction segments and faults, it is intended in this article to determine the most accurate method of seismic source modelling. Estimation of the maximum strong ground motion in this province has been assessed by assuming various combinations of activity rate contribution ratios, i.e. independent activity of either subduction source or faults or simultaneous activity of subduction source and faults. According to the obtained results, the maximum and minimum limits of the strong ground motion acceleration is related to the independent seismic activity models and when subduction source and faults are assumed to be contributing simultaneously to the activity rate of the region, the resultant ground motion acceleration will be between the limits obtained based on independent activity models.