Landslide hazards in the Wudongde Reservoir (China): Analysis of frequency-magnitude characteristics based on self-organized criticality theory

Abstract

To characterize the magnitude-dependent distribution of landslide hazards in the Wudongde Reservoir area, the principle of maximum complexity is employed to analyze the physical mechanisms governing power-law distributions of landslides. A frequency-magnitude distribution curve is derived using a power-law function, with a focus on investigating the statistical characteristics of landslide frequency-magnitude distributions and their deviation effects. Results indicate that when the geometric mean value is constrained and the system complexity reaches its maximum, the power-law distribution represents the most probable probabilistic model for landslide frequency-magnitude relationships. The bank landslides in Wudongde Reservoir exhibit self-organized criticality (SOC) characteristics, with their frequency-magnitude distribution curve comprising two distinct components: a power-law segment and a deviating segment. While the power-law function adequately describes the former, the double Pareto and inverse Gamma functions are found to better capture both the power-law behavior and deviation effects. Among these, the inverse Gamma function demonstrates superior goodness-of-fit, likely due to its ability to model tail behavior in complex systems. Notably, the deviation effect in the frequency-magnitude distribution is not attributed to single factors (e.g., geological genesis mechanisms, slide mass thickness, landslide branching patterns, or left/right bank positions) but rather arises from the synergistic interaction of multiple geological factors.