Terrain change detection using ASTER optical satellite imagery along the Kunlun fault, Tibet
Terrain changes are manifested in satellite images as pixel offsets. A pixel offset represents the apparent difference in the position of corresponding pixels in two time-separated images of the same portion of the Earth's surface. Previous work on Satellite Pour l'Observation de la Terre (SPOT) optical data has shown the feasibility of using optical imagery for terrain change detection using both “imageodesy” and Fourier analysis. This thesis attempts similar change detection with Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) imagery. The change detection methods used in this thesis are Fourier analysis, “imageodesy” using cross-correlation, and wavelet analysis. The benefits of using ASTER are its dramatically lower cost compared to SPOT, the capability of generating DEMs from ASTER imagery, and the redundancy afforded by ASTER's stereo capability. The latter may aid in increasing the precision of terrain change measurements made using optical image processing techniques. ^ Three test cases were used to test the three change detection methods. All test cases capture different regions of the Kunlun fault area in China, and have different time separation windows, where each window represents a different time interval from two years to two month. The Kunlun fault region experienced a Ms = 8.1 earthquake known as the Kokoxili earthquake on November 14, 2001. This earthquake caused a maximum of 16.3 m along the fault. Results have shown terrain change detection works best using the Fourier and wavelet analysis techniques. The Fourier analysis method detected the left-lateral slip direction and magnitude (4.5 m) in the proximal area of the Kunlun fault very well. Wavelet analysis was very effective at delineating fault scarps caused by the 2001 Kokoxili earthquake. ^
Schiek, Cara Gina, "Terrain change detection using ASTER optical satellite imagery along the Kunlun fault, Tibet" (2004). ETD Collection for University of Texas, El Paso. AAIEP10806.