Abstract
The 2015 Gorkha earthquake and its aftershocks induced landslides in central Nepal. In this study, field surveys were conducted, and Google Earth satellite images were analysed for pre- and post-mainshock and aftershock scenarios to clarify the distribution of landslides. A total of 13,097 new landslides and 750 enlarged landslides were identified and mapped as polygon-based data over an area of 7.8 × 103 km2 between the epicenters of the main shock and the largest aftershock at the mountainous southern margin of the High Himalayas. Shallow-disrupted landslides were the most common type of mass movement. The areas of individual landslides ranged from 10 to 3.2× 105 m2, covering a cumulative area of 5.4 × 107 m2 or 0.7% of the study area. The landslide density was high in the Gorkha, Rasuwa, and Sindhupalchok districts, indicating that these areas suffered greater damage. Landslides occurred mainly on steep slopes (>35°) in V-shaped inner gorges, on geologically controlled steep slopes such as the scarp slopes (infacing slopes) of mountain ridges, and on terrace scarps. The results suggest that earthquake-induced landslides occur on slopes preconditioned by topographic and litho-structural factors. Based on our observations, recommendations for the mitigation of future landslide disasters are provided.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have