Distribution and characteristics of landslides in the 2018 Palu earthquake, Indonesia

Abstract

The September 28, 2018 Mw7.5 earthquake of Palu earthquake, Sulawesi Island, Indonesia, has triggered a lot of landslides. We attempted to establish a detailed landslide inventory of this area, which is very important to understand the landslide distribution, geomorphic evolution and risk assessment of the earthquake. The purpose of this paper is to make a statistical analysis of the spatial distribution and influencing factors of landslides in the study area based on the landslide inventory of Palu earthquake. Combined with earthquake, topography, geology and other landslide influence factors, taking the percentage of landslide area (LAP) and landslide number density (LND) as indicators, the change trend of landslides in different factor intervals is analysed. The results show that the areas with elevation of 400-500 and 500 – 600m are prone to landslides. With the increase of elevation, LAD and landslide area showed a downward trend. LND first increased and then decreased, and reached the peak at the elevation of 1500-1600m. Large scale landslides are prone to occur in low altitude areas, while small scale landslides tend to occur in high altitude areas. LAD and LND increased with the increase of slope. The LAP decreases with the increase of the distance from the river, which is opposite to the LND, indicating that the small landslides often occur in the area far from the river. The results of this study are helpful to understand the causes of coseismic landslides. And provide a scientific reference for disaster prevention and mitigation of earthquake landslides in the seismic landslide hazard zoning.