Collaborative Research: Development, Experimental Validation and Case Studies for the Next Generation of Landslide Tsunami Models for Coastal Hazard Mitigation

University Of Delaware, Newark DE

Investigators

Abstract

Tsunamis create major geohazards for highly populated coastal areas. Mitigating tsunami risks is important for society and requires accurate source forecasting and modeling, including non-seismic near-field sources such as Submarine Mass Failures (SMFs), which are prevalent in some areas (such as the US East Coast), and performing runup/inundation mapping using propagation models. Tsunami inundation maps can be used to develop or revise zoning plans in order to make coastal communities more resilient. The methods developed in this project will improve tsunami hazard assessment and warning from subaerial slides (originating above water level) and SMFs, and could be adopted as the new standard for such analyses, in operational tsunami hazard assessment and inundation mapping work (e.g., such as done under the auspice of the US National Tsunami Hazard Mitigation program), and in new tsunami warning systems for non-seismic near-field sources; this could ultimately save lives. The project team will collaborate with foreign partners (at the University of Marseille (France), University of Dundee (UK), and British Geological Survey (BGS, UK)) to develop, implement, and experimentally validate the next generation models for deformable landslides and resulting tsunami generation. Subaerial slides entering the water column as well as SMFs originating underwater will be considered. The project team will study a range of slide rheologies, with particular interest in dilatational granular flows and in fragmenting, blocky cohesive soil layers.te Modern computational methods such as GPGPU-based Lattice Boltzmann schemes, will also be investigated with an aim to improving model efficiency and making models able to perform faster-than-real time simulations during near-field events, in order to issue early warning. In this respect, model predictions of seafloor motion and surface wave response will be studied in light of ongoing parallel efforts on High Frequency Radar and hydroacoustic detection methodologies. In collaboration with the BGS, new models will be applied to historical landslide tsunami case studies, where tsunami impact was measured (PNG 1998, Unimak 1946, and Ritter Island 1888 events), in order to achieve both a better understanding and modeling of landslide tsunami generation, as well as developing field benchmarks that can be used for model validation.