Deep-seated landslides in high mountain terrain typically deform slowly over years to decades, making their internal kinematics difficult to characterise from field observations alone. Here we investigate the Leo Pargil landslide on the southwestern flank of the exhumed Leo Pargil gneiss dome in the northwestern Indian Himalaya, a large active deep-seated gravitational slope deformation (DSGSD) in the region. Multi-temporal persistent scatterer interferometric synthetic aperture radar (PS-InSAR) analysis of Sentinel-1 data is combined with geological and structural information to characterise the landslide's present-day kinematics and internal segmentation. Ascending and descending Sentinel-1 data from 2018 to 2023 are combined to decompose InSAR-derived displacement into vertical and horizontal components, allowing spatial variations in displacement magnitude and direction to be resolved across the landslide body. The displacement field is strongly segmented, with faster-moving sections separated by sharp displacement gradients and relatively stable zones, indicating the presence of distinct internal sectors within the landslide. The upper part of the slope shows displacement patterns consistent with a rotational component near the headscarp, whereas the lower part is characterised by predominantly slope-parallel motion. Spatial variations in motion broadly follow mapped structural and lithological boundaries, indicating that inherited structures and slope geometry may influence the present-day deformation pattern. The results show that the Leo Pargil landslide is a segmented deep-seated gravitational slope deformation on the flank of an exhumed gneiss dome, with its present-day kinematics consistent with consistent with inherited structural heterogeneity and ongoing geomorphic processes.

Due to rapid and intense socio-environmental transformations in rockfall-prone areas, risk assessment accounting for non-stationary conditions becomes a crucial issue for supporting long-term land-use zoning and adapting mitigation strategies. During the past few decades, several studies have examined the impacts of global warming on rockfall activity, especially at high-elevation sites. By contrast, concomitant changes in exposure, such as modifications in road traffic with changes in mountain tourism and social practices, have received little attention, making the overall changes in risks largely unknown. This study therefore proposes a quantitative risk assessment (QRA) of the cantonal road in Balmatten (Zermatt Valley, Swiss Alps), which evaluates the respective and overall effects of rockfall frequency and traffic density changes on rockfall risks at three time steps: 1960, 2010 and 2060. The approach relies on strong, yet reasonable assumptions that minimize computational burden. Results demonstrate the significant impact of road traffic fluctuations (+818%) on risk estimates, which largely outweighs the effects of climate change (+100%) on rockfall risk over the 1960–2060 period. Despite several challenges inherent to the implementation of non-stationary QRA approaches, these findings demonstrate their value to support adaptation of mountain territories in a time of global change. • Non-stationary analyses are essential to capture socio-environmental evolutions. • Scenario-specific variables influence the primary driver of risk change. • Risk analysis was addressed by adapting hazard frequency and traffic exposure. • Integrating dynamic conditions in QRA can improve risk management strategies.