Signature of sediment CAscades following Landslides triggered by Extreme Events in the Stratigraphy

Catastrophic sediment release in fluvial systems is largely driven by landsliding that occurs naturally during extreme events such as earthquakes or storms in mountain belts.

Sediments cascade through the river system until they are stored either permanently in alluvial fans and lakes or temporarily in terraces.

To mitigate future landslide hazards, it is urgent to better understand past extreme events such as their amplitude and frequencies, which calls for an improved identification of a landslide signal in the stratigraphy.

The SCALEES (Signature of sediment CAscades following Landslides triggered by Extreme Events in the Stratigraphy) project aims to provide a calibrated and validated numerical model of multi-grain size sediment transport and storage that will be apply to unravel the signal of landslides preserved in lakes or alluvial fans and in terraces.

To do so, this numerical model that is a recent development of the established RIVER.lab landscape evolution model will be parametrised using extensive and unique data collected in New Zealand where co-seismic landslides have heavily impacted landscapes.

The combination of empirical data with numerical simulations will allow us to predict for the first time the full signal (all grain sizes) of sediment cascades preserved in the stratigraphy in response to an extreme event at the scale of a catchment.

The project builds up upon the complementary expertise of the fellow in the field of numerical modelling of sediment transport and storage, of the outgoing supervisor in sedimentology related to natural hazards and of the return supervisor in fluvial geomorphology.

Through the access to a unique dataset of post-earthquake records as well as scientific networks and the design of a detailed career development plan and a tailored training program, the fellow will be provided with a unique skill set to become an internationally recognised geomorphologist ready to tackle interdisciplinary research questions.