Abstract. Earthquake-triggered landslides have drawn much attention around the world because of the severe hazards they pose. The 20 April 2013 M s = 7.0 Lushan Earthquake, which occurred in the Longmen Shan region in Sichuan province, China, triggered more than 1000 landslides throughout an area of about 2200 km 2 , and completely blocked many roads and exacerbated overall transportation problems in the mountainous terrain. Preliminary landslide inventory is complied immediately following the earthquake, mainly based on the high-resolution remote sensing images. At the same time, the distribution of these landslides is statistically investigated to determine how the occurrence of landslides correlates with distance from the earthquake epicenter, slope steepness, seismic intensity and rock type. Statistic analysis is conducted using landslide point density (LPD), which is defined as the number of landslides per square kilometer. It is found that LPD has a strong positive correlation with slope gradients and a negative-exponential decline with the distance from the epicenter. The higher LPD values occur in younger strata systems like Quaternary and Tertiary sediments in the study area. Spatially, the triggered landslides are controlled by the causative faults and mainly concentrated around the epicenter. All the landslides are located within the area with seismic intensity ≥ VII and in line with seismic intensity. Generally, LPD value decreases with increasing distance from the epicenter, and sometimes landslides are densely distributed along the roads in the mountainous region. Also, this study reveals that the empirical relationship between distance and seismic magnitude is more suitable for estimating the landslide concentration area during the Lushan earthquake compared to other methods.

Abstract. Earthquake-triggered landslide has drawn much attention in the world because of severe hazards it causes. The Ms =7.0 Lushan earthquake which occurred on 20 April 2013, China, in the Longmen Shan mountain region triggered more than 1000 landslides and really blocked many roads and exacerbated the overall transportation problems in the mountainous region. Preliminary landslides inventory is complied based on the high-resolution remote sensing images. Based on it, landslides spatial distribution characteristics and correlations between the occurrence of landslides with geologic and geomorphologic conditions are analyzed. Statistic analysis is conducted by using landslide point density (LPD), which is defined as the number of landslides per square kilometer. It is found that LPD have strong positive correlations with slope gradients, and the landslides are likely to occur in younger strata systems like Quaternary and Tertiary sediments. Spatially, the triggered landslides are controlled by the causative faults in their distribution and mainly concentrate around the epicenter. All the landslides are located within the area with seismic intensity ≥ VII and in scale with the seismic intensity. LPD decreases with increasing distance from the epicenter, and sometimes landslides are found densely presented along the roads in the mountainous. It is found that the empirical distance–magnitude relation are more suitable for estimating the landslides concentrated area during the Lushan earthquake.