ObjectiveThe spatial distribution analysis of earthquake-induced landslides offers critical insights for identifying potential geological disasters in affected regions

which is fundamental for informing post-disaster reconstruction planning

relocation strategies

site selection processes

and the development of effective geological disaster mitigation measures. MethodsTaking the earthquake that struck Luding County

Ganzi

Sichuan Province

on September 5

2022

as a case study

earthquake-induced landslides were initially identified using artificial visual 3D remote sensing data. This analysis was based on an optical image (DOM) with a resolution of 0.2 meter and a digital elevation model (DEM) with a resolution of 0.5 meter

both acquired post-earthquake. Field investigations and subsequent corrections were performed to validate and finalize the landslide inventory. Subsequently

the relationships between the distribution of earthquake-induced landslides and various geological factors

including topography

geological structures

and earthquake parameters

were systematically analyzed. Results①The Luding earthquake triggered 9248 landslides

covering an area of approximately 680 km2

with the majority classified as small- to medium-sized. The highest landslide density was observed at the tectonic intersection of the Xianshuihe fault

Daduhe fault

and Jinping mountain fault. The cumulative landslide area reached approximately 45.57 km2

with an average landslide area of 4941 m2. ② The spatial distribution of landslide in the earthquake-affected region is predominantly controlled by PGA and fault structures

with the majority of landslides concentrated in areas where PGA exceeds 0.6 g and within 1 km on either side of the seismogenic fault. Furthermore

landslide occurrence exhibits a negative correlation with proximity to water systems and roads. At a local scale

topographic factors significantly influence landslide distribution

with the highest frequency observed at elevations ranging from 1200 to 2400 m

on slopes inclined between 30° and 60°

and predominantly facing east or southeast. Additionally

landslides are more prevalent in areas underlain by hard rock strata. ③ The number and area of landslides exhibit an exponential relationship with the magnitude of the Luding earthquake. Leveraging high-precision data

our analysis identified a significantly higher number of earthquake-induced landslides compared to previous studies

with a reduced minimum landslide area and an increased total affected area. ConclusionThe findings of this study have been implemented to support post-disaster recovery and reconstruction efforts in the Luding earthquake-affected region

providing a scientific basis for enhancing resilience and reducing future earthquake risks.