Monitoring surface deformation of an active landslide in the Yerba Loca area, Chile, using DInSAR technique with PAZ imagery
Vidal-Páez, P., Clavero, J., Droguett, B., Ramírez, V., Fernández-Sarría, A., Pérez-Martínez, W., Jaña, A., Sarricolea, P.
Abstract
Using 41 radar images from the PAZ satellite (2019–2021) and the SBAS-DInSAR technique, the study measured the movement of the Yerba Loca landslide, which began in 2018. The slope remains active: it subsides about 9.6 mm/yr and moves about 6.3 mm/yr downslope.
The study analyses the deformation of an active zone of about 4 hectares on the north-eastern slope of the Yerba Loca Nature Sanctuary, associated with the rotational landslide of August 2018 (≈2.5 million m³). Nineteen ascending-orbit and 22 descending-orbit images were processed, and the movement was decomposed into its vertical and east–west components.
Cumulative subsidence reaches −16.5 mm and horizontal displacement −13 mm. Periods of acceleration coincide with snowmelt and possibly the thawing of frozen ground. A preliminary comparison with Sentinel-1 images shows consistent results.
