Earthquake-Induced Change Detection in the 2003 Bam, Iran, Earthquake by Complex Analysis Using Envisat ASAR Data

The recently deployed Envisat satellite collected before- and after-event imagery on the Bam, Iran, earthquake that occurred on 26 December 2003. The majority of buildings in Bam were traditional one-story unreinforced adobe structures constructed of the indigenous land material of the region. As a result, the corresponding SAR imagery for Bam reflects less material dependence on object detection. For this study, two sets of before and after SAR data are used from the ASAR sensor onboard of the Envisat platform. The backscattering, complex coherence, self-power and cross-power values are computed for each respective co-registered data pairs. The change detection scheme evaluates these results using orbital information to assess the levels of change in different city zones. Such damage maps can potentially serve in disaster response/management and also in estimating economic losses (Eguchi et. al. 2000). Damage maps from field observations are used to validate these findings.