Runup Survey

On 17 October 2015, a mountainside collapse at the terminus of Tyndall Glacier in southeast Alaska generated a landslide-triggered mega-tsunami. The landslide sent approximately 7.6 × 10^7 m³ of rock and glacial sediment into Taan Fjord, abruptly displacing the water. The ensuing tsunami reached a peak runup of ~193 m on a steep slope directly across from the landslide, ranking among the highest tsunami runups ever documented. The wave inundated over 20 km² of terrain around Taan Fjord and Icy Bay, stripping forests and depositing sediment up to hundreds of meters inland. In summer 2016, a comprehensive field campaign surveyed the event, recording precise tsunami runup elevations, flow depths, and inundation distances at dozens of sites throughout the fjord and adjacent coastlines. Here we present the resulting datasets: a georeferenced catalogue of tsunami runup measurements, high-resolution topography and bathymetry data, and an extensive collection of field photographs. These data provide an quantitative record of a mega-tsunami’s onshore effects, intended as a benchmark dataset for landslide-tsunami modeling and hazard assessment. The Taan Fjord tsunami dataset will facilitate rigorous testing of landslide tsunami generation and propagation models and improve our understanding of the geomorphic consequences of large impulsive wave events in coastal and glacial fjord settings.