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A model has been developed of glacial erosion, transport and deposition based on empirical observations of till emplacement by modern glaciers, and in which it is assumed that the dominant mode of sediment transport is by subglacial deformation. A thermo-mechanically coupled ice sheet model, which is also coupled to bed deformation, is forced by a combination of free and given climatic parameters so as to match the geologically-inferred fluctuations of the ice sheet through the last glacial cycle. The model then generates patterns of sediment transport that determine the evolution of erosion and deposition. These are then compared with a variety of known properties, the large-scale distribution of till thickness, the dispersal of indicator erratics, patterns of relative sea level change, and the delivery of ice rafted detritus into the marine realm. Important conclusions of the model include the preservation in some areas of thick till masses emplaced during stadials prior to the glacial maximum, the structure of thick till masses in outer zones of glaciation and the importance of ice streams in determining the erosional/depositional mosaic.
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