HR: 16:15h
AN: C34A-02    [Abstracts]
TI: Landform Formation Under Ice Sheets
AU: * Schoof, C G
EM: cschoof@eos.ubc.ca
AF: Department of Earth and Ocean Sciences, University of British Columbia, 6339 Stores Road, Vancouver, BC V6T 1Z4 Canada
AU: Ng, F S
EM: felix@mit.edu
AF: Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139-4307 United States
AU: Hallet, B
EM: hallet@u.washington.edu
AF: Quaternary Research Centre, University of Washington, Box 351360, Seattle, WA 98195-1360 United States
AB: We present a new mathematical model for the formation of subglacial landforms such as drumlins under a warm-based, soft-bedded ice sheet. At the heart of the model is a channelized drainage system in which smaller channels grow at the expense of larger ones, leading to the continuous creation and extinction of drainage paths, and to a spatially distributed imprint on the landscape. We demonstrate how interactions between such a drainage system, bed topography and ice flow can lead to the spontaneous formation of subglacial landforms, and discuss the effect of different sediment transport characteristics in the drainage system on the shape and migration of these landforms. This mathematical model is the first component of a study of landscape/ice-sheet self-organization, which is inspired and guided, in part, by new digital topographic data (LIDAR) that are revealing with unprecedented detail the striking grain of glacially scoured topography on length scales ranging from 0.5 to 20 km.
DE: 3210 Modeling
DE: 1815 Erosion and sedimentation
DE: 1824 Geomorphology (1625)
SC: Cryosphere [C]
MN: 2004 AGU Fall Meeting