Ice-sheet surging and ice-strealll forlllation
نویسنده
چکیده
A simplified model of ice-sheet behayiour is described. I t combines the assumptions of rapid ice flow, high viscous actiyation energy and realistic sediment-based sliding dynamics to form a non-linear diffusion-type equation which can display relaxation oscillations analogous to those of surging glaciers, and which may be relevant to large-scale surges of the Hudson Strait and Cabot Strait ice streams of the Laurentide ice sheet. When the physics of this model is applied to a laterally extensi\'e unidirectional ice flow, such as that in the Siple Coast of Antarctica, an appropriate mechanism may exist for the spon taneous generation of ice streams.
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