Investigating persistent scatterer InSAR (PSInSAR)technique efficiency for landslides mapping: a casestudy in Artvin dam area, in Turkey

Abstract

Monitoring and determining landslides in dam reservoirs is very crucial as it is one of the main factors of dam failures in the world. Coruh river basin is one of the most important river basin in the Northeast part of Turkey which accompanies five big dams. Although persistent scatterer InSAR (PSInSAR) method is a powerful remote sensing technique which can measure and monitor displacements of the Earth’s surface over time, its validation is a challenging issue because of the heterogeneous PS data. In this study, the efficiency of PSInSAR is investigated by proposing two different validation methods in order to see the consistency of the determined mean deformation velocities obtained with series of Sentinel-1A SAR-images. In the first method, 3D coordinates of reference points are projected to 1D displacement values in line of sight direction and then compared with the radar displacements of PS points. In the second method, new displacement values of PS points around reference points are identified from an interpolation map in order to be compared with the original displacements of reference points. In the end, it is showed that the displacements found by PSInSAR method are consistent with the reference points’ displacements measured in the study area. Finally, this work’s specific objectives are to present solutions to the challenging validation problem, to show the effectiveness of PSInSAR method and to describe the remaining challenges in PS analysis of landslide applications in dam areas.