Application of ERS-2/SAR data for the 1999 Taiwan earthquake

The applicability of interferometric SAR (InSAR) for detection of urban damages and land displacements caused by The 1999 Great Taiwan earthquake (Chi-chi earthquake) occurred on Sep. 21, 1999 were studied based on the data acquired on ERS-2 repeated pass. Three ERS-2 SAR data acquired on Jan. 21, May 6, and Sep. 23 in 1999 were used, the former two were acquired before the earthquake occurrence and the third was acquired two days after the earthquake. Two major results are obtained from the study. The first is the verification on the effectiveness of coherence information for detecting the damaged urban areas by building collapse, and the other is the effectiveness of differential interferograms to extract land displacement patterns. The latter result also proves that the extracted land displacement pattern by InSAR is consistent in general with the result of GPS survey.