A review of topographical and geotechnical conditions for large-scale flow-type landslide induced by earthquakes

Abstract

This review discusses the mechanism of large-scale flow-type landslides, which are extremely rare geohazards, focusing on the topography and geotechnical conditions of the landslides that occurred in the 2018 Sulawesi earthquake in Indonesia and the 2023 Jishishan earthquake in China. It was confirmed that there were important characteristics in common that led to the occurrence of the landslides, such as the dry alluvial fan above the landslide area, the conditions of the flow and sedimentation areas, the presence of spring water, and the soil characteristics of the landslide area. In addition, although there is no record of a similar flow-type landslide in Japan in the past, there is a local folklore from the Middle Ages about a destruction of coastal village in Ikuji district of Kurobe City. This is an assumption based on limited information, however, the topography and geotechnical conditions of the Ikuji district are similar to those of the landslides in the Sulawesi earthquake, and it is possible that the landslides in Ikuji could be explained by the same mechanism.