Topographic and morphological effects of global earthquake- and rainstorm-induced landslides

• Landslides exhibit distinctive geometric characteristics due to different triggers. • Earthquake-induced landslides tend to be concentrated near ridges. • Rainstorm-induced landslides tend to be concentrated near valleys. • Compactness and major axis are negatively correlated for landslides. Landslides have different topographic and morphological characteristics due to their different triggering mechanisms. However, the differences in the characteristics of earthquake- and rainstorm-induced landslides remain unclear. In this paper, we collect 12 cases of earthquake- and rainstorm-induced landslides around the world and reveal the differences in characteristics of the two types of landslides. By examining the geometric characteristics and location distribution of the landslides, the results show that earthquake-induced landslides tend to have larger areas, perimeter, lengths, widths, area to perimeter ratios (area/perimeter), major axis ( S M ), and minor axis ( s m ) than rainstorm-induced landslides. In addition, earthquake-induced landslides have more complex, rounded, and compact shapes than rainstorm-induced landslides. Earthquake-induced landslides are predominantly clustered near ridges, whereas rainstorm-induced landslides are predominantly clustered near valleys. The results also indicate that earthquake- and rainstorm-induced landslides mostly occur on 30°–50° and 10°–30° slopes, respectively, and both types are more likely to occur on sunny slopes. Moreover, the compactness and major axis are negatively logarithmically correlated for earthquake-induced landslides, while they are negatively exponentially correlated for rainstorm-induced landslides. Additional earthquake- and rainstorm-induced landslide events have verified the reliability and extensibility of the research conclusions. This work is beneficial for the management of landslide hazards and the effective implementation of landslide prediction and risk assessment.