The 26 December 2003 Bam earthquake caused catastrophic damage to the city of Bam and neighboring villages. Large-amplitude ground-motions recorded at the Bam accelerograph station in the center of Bam city by the Building and Housing Research Center (BHRC) of Iran. We simulated acceleration records of the Bam earthquake at three BHRC strong motion stations (Bam, Abaraq, and Mohammad-Abad) using the empirical Green’s function (EGF) method. The EGF method is limited in a frequency range by signal-to-noise ratios of small events. In this study the frequency range was set to 0.5-10 Hz. For the simulation, the fault model of strike, dip, and rake = 176°, 88°, and 166° was considered. We estimated the size of the strong motion generation area for the mainshock as 11 km in length by 7 km in width. We used 1-D and also 2-D velocity structures across the fault, and also a combination source model to estimate the parameters for the strong motion generation area. We found the rupture starting point which best fits the simulated waveforms to observed ones is nearly in the middle of the strong motion generation area which reproduced near-source ground motions in a broadband frequency range.

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