Spatial Patterns and Scaling Distributions of Earthquake-Induced Landslides—A Case Study of Landslides in Watersheds Along Dujiangyan–Wenchuan Highway

Xuemei Liu,Yong Li,Jun Zhang,Ning Jiang,Taiqiang Yang,Xiaojun Guo,Pengcheng Su,Rui Xu

doi:10.3389/feart.2021.659152

Abstract

Earthquake-induced landslide has various spatial characteristics that can be effectively described with the frequency–area curve. Nevertheless, the widely used power-law curve does not reflect well the spatial features of the distribution, and the power exponent does not show the association with the background factors. There is a lack of standards for building the relationship, and its implication on the spatial distribution of landslides has never been analyzed. In this study, we propose a new form of frequency distribution and explore the parameters in the typical watersheds along the highway from Dujiangyan to Wenchuan in the Wenchuan earthquake region. The obtained parameters are related to the landslide density and proportions of the large-scale landslides. Furthermore, a hot spot analysis of landslides in the watersheds is conducted to assess the relationship between the parameters and the spatial cluster patterns of landslides. The hot spots highlight the size and distance of landslide areas that cluster together, whereas the distribution parameters reflect the density and proportions of landslides. This research introduces a new method to analyze the distribution of landslides and their association with the spatial features, which can be applied to the landslide distribution in relation to other influential factors.

Highlights

Earthquake-induced landslides have different spatial distribution characteristics, which depend on the tectonic features of the earthquake and the geomorphological conditions of landslides
We found that ρ can well reflect the density of the landslide area (Dl), and Ac coincides with Proportion of large-scale landslides (Pl), the proportion of large landslides, with a lower limit of 0.01 km2 as determined by
Research generally considers that the tail of the landslide frequency–area relationship fits the power law, but the relationship between parameters and the spatial distributions has never been analyzed

Summary

INTRODUCTION

Earthquake-induced landslides have different spatial distribution characteristics, which depend on the tectonic features of the earthquake and the geomorphological conditions of landslides. The first type includes the watersheds ZJL, QL, LT, and XF Their ρ values are negative, their landslide densities and areas are small, and distributions are dispersed (Figure 8A). The number and the degree of concentration of the large-scale landslides within the watersheds LQW, DY, and CDG are higher, and their Ac values are the highest and range from 0.0075 to 0.0081 (Figure 9C).

DISCUSSION AND CONCLUSION

Findings

DATA AVAILABILITY STATEMENT