Automatic processing of interferometric SAR and accuracy of surface deformation measurement

Interferometric Synthetic Aperture Radar (InSAR), one of typical application techniques of SAR data, is used to generate Digital Elevation Model (DEM) while it is also used to measure spatial surface deformation. The former and the later techniques are usually differentiated as InSAR and Differential InSAR respectively. In this paper, we focus the later technique as InSAR. We measured ground deformation using automatic InSAR processing and verified accuracy of obtained results. The study area is Zonguldak coalfield, located along the Black Sea coast approximately 240 kilometer away from Istanbul to the east, Republic of Turkey. In this region, underground coal mining has been undergoing since 1848 and 3 million ton per year of hard coal has been produced. Recently, this coal mining is found to be causing subsidence around this area. Since the whole damage has not been grasped, we tried to measure the amount of surface deformation using InSAR. As a result, some phase anomalies were detected just above mining drifts, and the largest deformation amounts among those was 204 millimeter per 4.5 months in slant range direction. In addition, InSAR results are corresponded with GPS measurement results within 9 millimeter variations.