Repeated glacial-interglacial cycles during the Quaternary have significantly impacted the topography of many mountain belts around the world. In recently deglaciated landscapes, the transition from glacial to fluvial/hillslope processes have induced transient adjustments in postglacial landscapes. Understanding the timescales over which these adjustments occur and how they compare to ~40-100 thousand-year periods of Quaternary glacial-interglacial cycles is a key question for understanding how Earth’s topography responds to periodic climatic perturbations during the Quaternary. In postglacial environments, the large amounts of sediments inherited from glacial periods and generated through landsliding of oversteepened glaciated topography may act as a fundamental control on the incision of postglacial rivers through the “tool and cover” effect. In this project, we focus on using numerical modeling to investigate the impact of inherited glacial sediments and hillslope-derived sediments on postglacial fluvial incision rates. We hope to constrain the erosion history of postglacial rivers and quantify the response timescales of postglacial topography to deglaciation.

Project investigators:  Dr. Jingtao Lai and Dr. Kim Huppert