Interpretation and sensitivity analysis of the InSAR line of sight displacements in landslide measurements

Landslides are major geological hazards and frequently occur in mountainous areas with steep slopes, often causing significant loss. Interferometric Synthetic Aperture Radar (InSAR) has been widely used landslide measurement over the last three decades. However, InSAR only can measure one-dimensional displacements (i.e. those radar’s line of sight (LOS) direction), resulting uncertainty between LOS displacement real slope displacement. In this paper, based on ascending descending data from Sentinel-1 satellite, a wide-area potential early identification was carried out using SBAS-InSAR whole Mao County, area western Sichuan (China), total 41 landslides successfully detected. Based quantitative analysis, results show that values aspect gradient-dependent. Finally, we innovatively derived sensitivity map measurement, revealing relationship displacement, slopes arbitrary aspects gradients, SAR geometric distortion. This is generalized finding useful for any slopes. It provides theoretical support to acquire understand which vital assist correctly interpreting carrying subsequent engineering analysis.