Abstract Slope stability is influenced by many factors, including the subsurface structure, steep topography, rainfall intensity and human activities. The Metline landslide, located south of Metline city in northern Tunisia, was triggered following heavy precipitation and has caused significant damage to several constructions and public infrastructures such as the regional road, the Metline High School and many public housing. In this study, integrated geophysical and geotechnical investigations were conducted to characterize the landslide's geometry and internal structure, identify the sliding surface and lateral extent and investigate the main factors controlling its occurrence. In situ geotechnical monitoring and laboratory geotechnical tests have been carried out. The electrical resistivity tomography (ERT) technique was applied through three profiles acquired with the Wenner array configuration. The Res2Dinv software was used to process the resistivity data. The results of the geotechnical tests show that the water content varies between 15% and 35%. The Casagrande plasticity chart indicates that the subsoil is formed by two clayey horizons classified as medium to high plasticity clays. The inverted ERT models reveal two main geo‐electrical layers; the first one is a resistant layer characterized by resistivity values ranging between 12 and 95 Ω m. The second layer is a conductive layer with resistivity values lower than 8 Ω m. The correlation between the inverted resistivity models and borehole data enabled the identification of rupture surfaces located at depths between 5 and 10 m. The integrated interpretation further allowed for a more precise delineation of the landslide's lateral boundaries and the identification of the main conditioning factors controlling slope instability at the site.
Sabrine et al. (2026) studied this question.