InSAR phase gradient reveals fault‐zone controls on the spatial distribution of slow‐moving landslides in the active orogenic region of Hazara‐Kashmir, Pakistan

• Published in: Earth surface processes and landforms
• Main Authors: Ahmad, Said Mukhtar, Fu, Lv, Wang, Teng
• Format: Journal Article
• Language: English
• Published: 05-11-2024
• ISSN: 0197-9337; 1096-9837
• DOI: 10.1002/esp.6015

Slow‐moving landslides play important roles in the landscape evolution and hazards planning. Studies along some strike‐slip faults have shown that the geological structures and bed‐rock lithology significantly contribute the distribution of slow‐moving landslides. However, controls on the distribution of slow‐moving landslides are poorly constrained in active orogenic regions, hindering our understanding of its role in the rapid orogenic process. The Hazara Kashmir Syntaxis in Pakistan is such a prominent geological structure of lesser Himalaya, where the inventory of slow‐moving landslides is scarce. Here, we attempt the interferometric synthetic aperture radar phase‐gradient stacking coupled with a deep‐learning system to provide the first slow‐moving landslides inventory (1066 presently active landslides, 2016–2023) in the Hazara‐Kashmir region. Along with optical imagery and field investigations, we analyse the impacts of fault structures, bed‐rock lithology, topography along with spatial distribution of earthquake and precipitation on the distribution of these slow‐moving landslides. We find that 33% of the detected slow‐moving landslides are distributed within 1000 m to active faults, and show a decreasing trend moving away from fault zones. This pattern strongly suggests that the active thrusting faults in this region significantly controls the distribution of slow‐moving landslides, while topography and precipitation show less impacts. Our study reveals the spatial distribution of slow‐moving landslides in a tectonic complex region with rapid orogenic process, and thus shows potential implications in geomorphology modelling and hazards evaluation for many less‐monitored, contemporary uplifting high‐mountain regions.