EGU2020-10545, updated on 29 Jan 2024
https://doi.org/10.5194/egusphere-egu2020-10545
EGU General Assembly 2020
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.

Post-earthquake hazard assessments might become rapidly ineffective under rapidly-evolving landslide controls

Ali P Yunus1, Xuanmei Fan1, Gianvito Scaringi2, and Filippo Catani3
Ali P Yunus et al.
  • 1Chengdu University of Technology, State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu, China (yunusp@csis.u-tokyo.ac.jp)
  • 2Institute of Hydrogeology, Engineering Geology and Applied Geophysics Faculty of Science, Charles University
  • 3Department of Earth Sciences, University of Firenze, Italy

Strong earthquakes, especially on mountain slopes, generate unconsolidated deposits of regolith, prone to remobilization by aftershocks and rainstorms. Assessing the hazard they pose and what controls their remobilizations in the years following the mainshock has not yet been attempted, primarily because of the lack of multitemporal landslide inventories. By exploiting a multitemporal inventory (2005–2018) covering the epicentral region of the 2008 Wenchuan earthquake and a set of predictor variables (seismic, topographic, and hydrological), we perform statistical tests to understand the evolution of controlling factors for debris remobilization in time. Our analyses, supported by a random-forest susceptibility assessment model, reveal a prediction capability of seismic-related variables depleting with time, as opposed to hydro-topographic parameters gaining importance and becoming predominant within a decade. Results may have important implications on the way conventional susceptibility/hazard assessment models should be employed in areas where coseismic landslides are the main sediment production mechanism on slopes.

How to cite: Yunus, A. P., Fan, X., Scaringi, G., and Catani, F.: Post-earthquake hazard assessments might become rapidly ineffective under rapidly-evolving landslide controls, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10545, https://doi.org/10.5194/egusphere-egu2020-10545, 2020.