Surface rupture, source parameters and building damage of the Bam 2003 earthquake constrained by radar interferometry

Category GIS & Remote sensing
Group GSI.IR
Location The 3 Symposium of Geosciences
Author Talebian, M. (۱), Ghorashi M. (۱), Nazari H.(۱), Jackson J. (۲), Fielding E. (۳), Funning G. (۴).
Holding Date 30 July 2007

The ۲۶ Dec ۲۰۰۳ Bam earthquake was the latest in a series of earthquakes on the north-south right-lateral strike-slip fault systems on the west side of Dasht-e Lut, Iran since ۱۹۸۱.

We use the interferometric correlation from Envisat SAR (synthetic aperture radar)images to map the details of the surface ruptures related to the devastating earthquake.Modelling of teleseismic bodywaves and radar interferogram phase, together with field observations suggest that over ۲ m of slip occurred at depth on a fault that had not previously been identified. This fault consist of three major N-S segments in the saoutj of Bam and passes directly into the centre of the city.About ۵ km to the east of the ۲۰۰۳ rupture, a prominent escarpment runs N-S for about ۱۰ km. Geomorphic features and pattern of streams suggest that the escarpment is a growing anticline above a west dipping blind thrust. No major offset was observed along the escarpment but modelling of teleseismic long period P and SH waveform as well as SAR interferogram suggest that the thrust at depth has also moved over ۱ m during the Bam earthquake. Another fault north of Bam shows offset and low correlation over a wider zone in theinterferograms, but it has no discrete surface rupture.

tags: QAZVIN