Satellite InSAR for Vegetated Landslide Analysis: Highway 4, Slovenia

Summary

Abstract

Slovenia is characterized by complex geology and high landslide susceptibility, with a particular concentration in the Vipava Valley, an area situated near the border between Italy and Slovenia. This region poses significant challenges for traditional monitoring due to its topography and dense vegetation. This paper explores the application of InSAR satellite monitoring, specifically using ALOS-2 constellation data, to understand the dynamics of existing landslides in the Rebrnice area , which is crossed by a major national motorway. Satellite radar interferometry (InSAR) is a space-based remote sensing technology capable of mapping ground and structural motions over small and wide areas with millimeter precision. Given its ability to monitor wide areas, it also helps assess the stability of slopes around linear infrastructures. InSAR products provide dense arrays of measurement points (thousands per km²) from reflections of pre-existing ground features (eg. rocks and manmade structures). Consequently, the technique does not rely on any ground-based instrumentation, offering significant cost savings and health/safety benefits by eliminating the need for site visits. The paper will discuss InSAR's advantages in detecting millimetric movements over large and inaccessible areas, observed deformation velocities and active area identification. Integrating satellite data with in-situ observations and measurements is essential for comprehensive assessment and proactive landslide risk management. These studies aim to promote wider acknowledgment of InSAR technology's capabilities for the benefit of dam and reservoir safety globally.