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USING HIGH-RESOLUTION SATELLITE IMAGERY TO PROVIDE RAPID POST-EARTHQUAKE DAMAGE ASSESSMENT

GRADUATE RESEARCH ASSISTANT: Kyu-seok Woo
COLLABORATOR: M. Crawford (Co-PI)

FUNDED BY: USGS National Earthquake Hazard Reduction Program

DESCRIPTION
This US Geological Survey (USGS)-sponsored project involves using high-resolution satellite images from the recent Northern Algeria earthquake (May 2003) and Bam, Iran earthquake (December 2003) as test beds for investigating methodologies to identify building damage from digital satellite images. This study will develop semi-automated methodologies that use various image characteristics to identify damaged urban areas. The image characteristics in damaged and undamaged areas of post-event images will be studied, as well as changes in characteristics between pre- and post-event images.

Figure 1 are pre- and post-earthquake Quickbird satellite images of a test area within the city of Bam that was used to investigate change detection algorithms for identifying earthquake damage. This area contains significant damage (collapsed structures) within the central and eastern sections, but almost no damage along the western edge. The change detection algorithm uses changes in texture to identify earthquake damage. The texture measure variance was found to best distinguish damage, and change was quantified by computing the correlation coefficient between the variance values of the pre- and post-earthquake images. The damage areas identified using this algorithm are shown in red in Figure 2. The algorithm correctly identifies a concentration of damage within the eastern and central parts of the image.

Figure 1 - Click on image to enlarge

Figure 2 - Click on image to enlarge

PUBLICATIONS
Rathje, E.M., Crawford, M., Woo, K., and Neuenschwander, A. Submitted. "Damage Patterns from Satellite Images from the 2003 Bam, Iran Earthquake," submitted to Earthquake Spectra, Earthquake Engineering Research Institute.

Rathje, E.M., Woo, K., Crawford, M., and Neuenschwander, A. 2005. "Earthquake Damage Identification using Multi-Resolution Optical Satellite Imagery," International Geoscience and Remote Sensing Symposium, IEEE, Seoul, South Koera, July.

Rathje, E.M., Kockar, M., and Ozbey, M.C. 2005. "Observed Site Effects During the 1999 Chi-Chi Earthquake and its Aftershocks," Siesmological Society of America Annual International Geoscience and Remote Sensing Symposium, IEEE, Seoul, South Korea, July.

Rathje, E.M., and Crawford, M. 2004. "Using High Resolution Satellite Imagery to Detect Damage from the 2003 Northern Algeria Earthquake," Paper No. 2911, 13th World Conference on Earthquake Engineering, Vancouver, Canada, August.

Rathje, E.M. and Crawford, M. 2003. “Earthquake Damage Identification Using High-Resolution Satellite Images from the 2003 Northern Algeria Earthquake,” Workshop on Application of Remote Sensing Technologies for Disaster Response, University of California, Irvine, CA, September.