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Key research themes
1. How do seismic, geological, and topographical factors control the spatial distribution of coseismic landslides and aid in identifying seismogenic faults?
This research theme investigates the spatial patterns of landslides triggered immediately by earthquakes (coseismic landslides), focusing on how various factors such as seismic shaking parameters, terrain morphology, lithology, fault proximity, and earthquake magnitude govern their occurrence and distribution. Understanding these relationships not only supports reliable landslide susceptibility assessment but is also instrumental in revealing hidden or blind seismogenic faults, especially when surface rupture is absent or unclear. Accurately characterizing these spatial distributions contributes to seismic hazard assessment and risk mitigation.
Key finding: Based on a detailed polygon-based inventory of 1883 coseismic landslides covering 8.11 km2 triggered by the 2017 Ms 7.0 Jiuzhaigou earthquake, the spatial distribution of landslides was statistically correlated with seismic... Read more
Key finding: Mapping of over 10,000 coseismic landslides induced by the Mw 7.8 Kaikōura earthquake revealed a strong spatial association of medium to large landslides with surface-fault ruptures, where landslide density within 200 m of... Read more
Assessment of earthquake-triggered landslide susceptibility considering coseismic ground deformation
Key finding: Introducing coseismic ground deformation as a novel influencing factor improves landslide susceptibility modeling in buried-fault earthquakes lacking obvious surface ruptures, as demonstrated using the 2004 Mid-Niigata... Read more
Key finding: A systematic regional study of earthquake-induced landslides (EQILs) triggered by magnitude ≥4.5 earthquakes in Norway, an intraplate setting with low-to-moderate seismicity, identified 22 landslides triggered by eight... Read more
2. What are the temporal patterns and mechanisms of earthquake-accelerated landslides (EALs) beyond immediate coseismic failures?
This area focuses on landslides that do not fail instantly during an earthquake but experience accelerated movement or velocity increase triggered by seismic shaking, often continuing for months to years after the event. These earthquake-accelerated landslides represent a subtle but critical long-term seismic hazard as they may damage infrastructure progressively or evolve into failures. Satellite radar (InSAR) observations enable the detection and monitoring of these slow-moving landslides across large regions and provide insight into their spatial clustering, triggering conditions, velocity evolution, and recovery behavior, expanding the understanding of post-earthquake landslide dynamics beyond the traditionally studied coseismic landslides.
Key finding: Using six years of Sentinel-1 satellite radar data, the study established a large inventory of 819 earthquake-accelerated landslides (EALs) triggered by the 2016-2017 Central Italy earthquake sequence, revealing that EALs... Read more
Key finding: Field surveys over three years after the 2015 Mw 7.8 Gorkha earthquake documented the continued activity and enlargement of most earthquake-triggered landslides, with only five sites showing slight activity reduction.... Read more
Key finding: Through the compilation and statistical analysis of a global database comprising 277 earthquake-induced and non-earthquake landslides with detailed measured rupture geometries, this study characterizes typical 3D landslide... Read more
3. How do combined triggers of earthquakes and rainfall influence landslide occurrence and evolution, and how can landslide susceptibility be assessed in such multi-hazard contexts?
Given that landslides are frequently induced by complex interactions of seismic shaking and hydrological processes, this research theme examines the synergic effects of earthquakes and rainfall on landslide triggering and reactivation. It evaluates how hydrological disturbance (e.g., rainfall infiltration, snowmelt) modulates the stability of slopes preconditioned by earthquake shaking and debris deposition. Integrated analyses, employing satellite data, field surveys, and data-driven susceptibility modeling, address how slope saturation, land use disturbance, and rainfall intensity/duration interact with seismic factors. These studies emphasize the need to consider combined triggers for accurate landslide hazard and risk assessment, particularly in earthquake-prone and climatically variable regions.
Key finding: Using satellite-derived landslide datasets and a random forest algorithm in southern Taiwan, this study developed an integrated hazard index capturing interaction effects of earthquakes and rainfall (IHERI) alongside a land... Read more
Key finding: The 2008 Wenchuan Mw 8.0 earthquake induced massive landslides that deposited large volumes of loose sediment in gullies. Subsequent intense rainfall events, exceeding critical intensities (e.g., >10.31 mm/h or 54.67 mm/d),... Read more
Key finding: Field surveys documented that monsoon-triggered new landslides frequently developed in earthquake-weakened slopes, with rainfall following the 2015 Gorkha earthquake critically contributing to continued slope failures. The... Read more