Glacial erosion of the underlying bedrock depends on the conditions at the bed: a cold-based glacier is frozen to the bedrock, while a glacier with its bottom at the pressure melting point can slide over the bedrock and cause erosion. Cosmogenic nuclide studies in landscapes such as Scandinavia that were glaciated during the Quaternary glacial cycles suggest a complex pattern of glacial erosion:while some areas have been substantially eroded around the last glacial maximum or even later, others seem untouched by a number of recent glacial cycles. Using the shallow ice approximation that holds well for large ice sheets, we are modelling the temperature regime, sliding conditions, and the resulting glacial erosion pattern under the Scandinavian ice sheet over the Quaternaryglacial cycles. By attempting to reproduce the broad patterns of denudation observed in the cosmogenic nuclide studies with a simple glacial erosion model, we hope to understand the impact of a dynamic ice sheet on the underlying landscape over a time scale of multiple glacial cycles.

Project main investigators: Erik Tamre and Jean Braun