Mapping active fault associated with the 2003 Mw 6.6 Bam (SE Iran) earthquake with ASTER 3D images

Satellite images reveal the geomorphology and geometry of an active fault associated with an earthquake that caused over 40,000 deaths in southeast Iran. This earthquake, of moment magnitude (Mw) 6.6, occurred at 01:56:52 (UTC) on December 26, 2003 near the towns of Bam and Baravat. An active fault that ruptured during the earthquake can be seen on three-dimensional (3D) pre- and post-earthquake images generated from Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) visible and near infrared (VNIR) data. The interpretation and analysis of satellite images suggest that a dextral fault extends for 65 km through the Bam-Baravat region. It strikes north–northwest and steps leftward at a segment boundary between two towns. Transpressional stress at this step-over (bend) probably triggered the 2003 earthquake rupture, as suggested also by source mechanism solution of the Bam earthquake and by landforms observed in the field. In the past 2000 years, Bam has had no earthquake as destructive as the one in 2003. The potential for this catastrophe could have been identified through a combination of satellite remote sensing technique and field reconnaissance.