Landslide Hazards Identification and Evaluation along the Vakhsh River in Tajikistan based on InSAR Time Series and the MassMov2D Model

Abstract

The boundary zones of compressive orogenic belts are particularly susceptible to active landslides due to high topographic relief and intense erosion. The Nurek section of Vakhsh River, located on the western margin of the Pamir orogenic belt, is characterized by complex terrain and severe water erosion. Therefore, the identification and interpretation of potential landslides are significant for regional hazard risk assessment. This study uses Interferometric Synthetic Aperture Radar (InSAR) data and the Small Baseline Subset (SBAS) method to evaluate the potential landslides from October 2017 to December 2023 in this river section, which is prone to frequent landslide occurrences. The results show that six potential landslides were identified, mainly concentrated on the west bank of the river, only one exhibited an annual line of sight (LOS) deformation rate exceeding 50 mm/year. Two-dimensional deformation analysis indicates a strong association with terrain relief, influenced by rainfall and soil conditions. Numerical simulations of mass movement indicate a low likelihood of the landslide transitioning into rapid or full-scale failures under experimental conditions. This study provides a timely riverbank landslide evaluation workflow using InSAR and numerical modeling, which can be widely applied to other steep riverbanks in Central Asia where in-situ monitoring is insufficient.

Keywords

landslide / risk evaluation / SBAS-InSAR / MassMov2D / Vakhsh River

RIGHTS & PERMISSIONS

2025 Geological Society of China