Landslide deformation monitoring with ALOS/PALSAR imagery: A D-InSAR geomorphological interpretation method

The objective of this work is to propose a geomorphologically-guided method for the interpretation of L-band ALOS/PALSAR interferograms created by Differential Interferometric Synthetic Aperture Radar (D-InSAR). The interferograms are used to estimate the deformation pattern of two rapid and large landslides (Poche, La Valette; South East France). The wrapped and unwrapped phase values are interpreted for different movement types (rotational, translational, and complex sliding) and two ranges of surface displacement rates. Kinematic sub-units are detected for both landslides, and zones affected by enlargement or retrogression are identified. The InSAR-derived displacement rates are consistent with ground-based measurements and with remote estimates of the displacement from C-band and X-band satellite SAR sensors. The results demonstrate the potential of L-band ALOS/PALSAR imagery for the monitoring of active landslides with important changes in the soil surface state and covered by vegetation.