Evolution of integrated fluvial networks on formerly glaciated low-relief landscapes

Abstract:

Continental glaciation throughout the Quaternary created low-relief landscapes in central North America and northern Europe by eroding bedrock highs and depositing a blanket of sediment. Pre-glacial drainage networks were substantially altered and landscapes left after retreat of the ice featured both deeply incised glacial meltwater channels and areas of internal drainage disconnected from regional base level. The evolution of these glacially-shaped landscapes toward integrated fluvial networks is evident from comparison of areas with different amounts of time since their most recent glaciation. I present a morphological analysis of landscapes across the Midwestern United States developed on glacial surfaces of differing age and a conceptual model describing the processes driving fluvial network evolution.