An Investigation into Ground Movement on the Ventnor Landslide Complex, UK Using Persistent Scatterer Interferometry

Analysis of ground movement rates along the coastline and upper sections Ventnor landslide complex was carried out utilizing Persistent Scatterer Interferometric Synthetic Aperture Radar methods using Sentinel-1 SAR data from 2015 to 2019 (four years). Results were compared with rainfall data, historical investigation records monitoring surveys at relate observations geology, geomorphology rainfall. Decomposition InSAR viewing geometries vertical horizontal aligned well previous ground-based studies. Subsidence −9.8 mm a−1 Lowtherville Graben heave +8.5 south Park observed. east-west geometry results showed an eastward displacement approximately 12.4 Park, a westward −3.7 throughout built up town, indicating displacing more in eastern direction than vertically. The cause this investigated by publicly available intrusive boreholes paired Interferometry, new model spanning parallel presented. No evidence significant observed heavily protected coastline, suggesting coastal defences comprised concrete aprons rip rap appear be effective management/landslide stabilisation tool when alone. mechanism increased stability is likely due combination toe weighting reduced erosion. A lag 13–20 days between high events subsequent peaks displacement, which shorter 29 day study. Similar prolonged resulting displacements also study demonstrates capabilities PSI methodology identifying same movements that conventional provide. By providing detailed analysis deformation landslide, we demonstrate small movements, validated existing surveys. can applied landslides urban environments worldwide, relatively cheap rapid resource for monitoring.