Bam Earthquake of 26 December 2003, Mw6.3; A Review on the strong Motions and Surface Deformations

The Bam earthquake of 26 December 2003(Mw6.5) occurred at 01:56:56(GMT,05:26:56 local time) around the city of Bam in the southeast of Iran. The Bam earthquake of 26/12/2003 (Mw6.5) has demolished the city of Bam, having a population of about 100000 at the time of the earthquake. The Bam fault-which was mapped before the event on the geological maps-has been reactivated during the 26/12/2003 earthquake. It seems that a length of about 10km (at the surface) of this fault has been reactivated. where it passed exactly from the east of the city of Bam. The fault has a dip towards the west and the foci of the event was located closed to the residential area(almost beneath the city of Bam). This caused a great damage in the macro seismic epicenter zone: however the strong motions have been attenuated very rapidly, especially towards the east-and west (fault normal) direction. The vertical directivity effects caused the amplification of the low frequency motions in the fault -normal direction as well as the greater amplitude of the low frequency motions in the fault-normal direction as well as the greater amplitude of the motion on the vertical direction.