Landslides

…and the mantle, while earthquakes, landslides, tsunamis and eruptions can trigger one another. Researchers will integrate geology, geophysics, geochemistry and geodynamics across scales to understand cascading hazards, improve forecasting and relate deep processes to surface landscapes and climate-linked risks. Attendance applications are reviewed and capacity may fill before the application deadline.

Abyssal marine turbidites provide some of the longest and most spatially extensive records of subduction zone earthquake recurrence globally; however, correlation of these deposits over long distances and interpretation of synchronous emplacement requires both an understanding of the turbidite generating systems and precise dating. Here, we present an integrated suite of high-resolution bathymetry, subbottom profiles, and sediment cores from combined autonomous underwater vehicle, remotely operated vehicle, and ship-based studies at a key paleoseismic site in the southern Cascadia subduction z

Precipitation-triggered geohazards, including landslides, debris flows, flooding, erosion, and scour, present growing challenges as hydroclimatic extremes intensify. This presentation describes an integrated framework that combines physics-based probabilistic hazard modeling with holistic, multimodal monitoring to support detection, forecasting, prioritization, and management of geohazard risk. The framework incorporates InSAR, optical imagery, lidar, and field observations within a structured escalation pathway that links regional-scale screening with targeted investigation and decision suppo

Hillslope mass wasting can have an outsized impact on both long-term landscape evolution and short-term hazards. Inputs of coarse sediment can shield river beds, alter local flow hydraulics, and impede fish passage. This talk focuses on the Fraser Canyon in British Columbia, a 375 km reach of the Fraser River where the 2018 Big Bar Landslide temporarily blocked the river and created a hydraulic barrier to salmon migration. I will examine the history of landsliding in the Fraser Canyon, evaluate hillslope morphology and valley connectivity to identify areas susceptible to future river-impacting

Landslides remain a major global hazard, with thousands of events each year posing significant impacts to human life, infrastructure, and ecosystems. While advanced constitutive models enable detailed slope-stability analyses at the single-hillslope scale, a critical gap persists in assessing landslide hazards at the community scale. Existing regional-scale models often struggle to balance physical rigor, predictive accuracy, and computational efficiency. They rely either on empirical approaches with limited physical basis or on mechanistic formulations that rely on major simplifying assumptio

Rivers grow by moving their drainage divides. Drainage divide migration can be (1) gradual, and widely distributed, such that each stream grows headward by similar amounts, or (2) rapid, and narrowly focused, such that a single stream grows at the expense of its neighbors and carves a gorge. Do rivers share the wealth? Or is most of the water and attention grabbed by just a few? This talk describes patterns of drainage divide migration, downstream river incision, and bedrock landslide occurrence in two landscapes developed in gently-dipping sedimentary rock. First, we quantify drainage divide

…series, we analyze deformation of 437 landslides across a ∼300 x 400 km area and group time series by relative velocity changes to identify anomalously fast motions. We test associations with external drivers (PGA, precipitation) and landslide attributes (slope, aspect ratio, area). Shaking from the 2022 event shows the strongest association with faster sliding rates. For slides that experienced higher

…framework capable of detecting landslides in near real time, estimating their size, and identifying landslide-dam formation, providing a practica

This talk focuses on cascading river hazards in Taiwan generated by landslides triggered by earthquakes and tropical cyclones. Drawing on case studies from Typhoon Morakot and the 2024 Hualien earthquake, I explore how sediment pulses move through river systems, reshaping channels and sustaining hazard long after the initial event. Together, these examples show how extreme events can produce lasting and evolving impacts in steep landscapes.

…of hillslope creep, rock avalanches, landslides, debris flows, and concentrated pyroclastic density currents. Despite their prevalence, the mechanics of these granular systems remain highly enigmatic. To link external observations to internal states, we utilize particle-resolved numerical methods. By simulating both gravity-driven and fluid-destabilized granular beds, we track the fundamental grain-scale processes that govern macroscopic failure. We find that the entire lifespan of a granular f

…of previously documented bedrock landslides. We present an inventory of large rock slides and rock avalanches for which pre- and post-event topography data are available, examine failure surface shapes using post-event topographic data, and evaluate the suitability of different geometries for approximating bedrock landslide failure surfaces and volumes.

…enable identification of active landslides, characterization of spatial patterns of motion, and tracking of temporal changes relevant to landslides.

Shallow landslides typically involving just the soil mantle constitute both a primary process driving landscape evolution and a significant geologic hazard. Theory for and empirical documentation of shallow landslides generally assumes that the elevated pore pressures that destabilize soils arise from runoff just within the soil. In many landscapes, however, it has been recognized that groundwater emerging from underlying weathered bedrock can generate destabilizing pore pressures. Here, we develop a coupled hydrologic and slope stability model that explicitly explores how a conductive bedr

In the past decade, several fatal landslides have impacted Southeast Alaska, highlighting the need to advance our understanding of regional geomorphic and atmospheric controls on triggering events and runout behavior. A large and long runout landslide on Wrangell Island, with area in the top 0.5% of >14,760 slides mapped in the Tongass National Forest, initiated during an atmospheric river event in November 2023 and traveled >1 km downslope, causing six fatalities. We used field observations, sequential airborne lidar, geotechnical analyses, and climate data to characterize the geomorphi

…This triggered numerous landslides and devastating flooding, and has changed the landscape of the Blue Ridge and mountain communities. This mapping and assessment of the landslides was conducted as part of the USGS Landslide Assessments, Situational Awareness and Event Response Research (LASER) and in cooperation with the North Carolina Geological

…triggering over 3,600 coseismic landslides. Roughly a month later, a rare atmospheric river event delivered up to 183 mm of rainfall in just 20 hours to the earthquake impacted region. This extreme precipitation induced additional landslides, debris flows, and flooding. In our research, we conduct a probabilistic landslide hazard assessment using the open-source Landlab earth surface modeling library, integrating both seismic and climatic drivers. The model incorporates earthquak