Mathematics – Logic
Scientific paper
Dec 2006
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2006agufm.p31a0114b&link_type=abstract
American Geophysical Union, Fall Meeting 2006, abstract #P31A-0114
Mathematics
Logic
5418 Heat Flow, 5422 Ices, 5462 Polar Regions, 6225 Mars
Scientific paper
The purpose of this study is to use numerical modeling to constrain the modern basal shear stress conditions on Mars and to interpret the results in terms of bed environmental conditions. We are using the classic Bingham (perfectly-plastic) model of ice flow extended to 3D geometries, nonuniform threshold shear stresses, and complex bed topography to create 3D reconstructions of ice-cap geometry and flow lines in the polar regions of Mars. This model assumes that ice sheets or glaciers move when a threshold basal shear stress is exceeded. Benchmark calculations on terrestrial ice sheets and glaciers indicate that this model, while simplified, can be used to accurately estimate the ice surface topography of ice sheets. The inputs to the model are: bed topography, a "mask" grid that defines the position of the ice terminus, and the threshold basal shear stress. The use of the model for Mars applications is justified by its general effectiveness regardless of the complexities of deformation, by the existence of a geomorphological basis for consideration of thawed beds (observation of U shaped valleys and other wet-based glacial bedforms) and the requirement of few parameters that are difficult to constrain. Several craters partially buried beneath ice were identified in DEMs, constructed from MOLA data, of the Martian polar regions. The exposed parts of the craters were used, together with the symmetry of the crater form, to estimate the morphology of the crater rim buried beneath the ice lobe and forward modeling is being used to construct families of ice lobes corresponding to different rheological and/or climatic conditions. These reconstructions will then be compared to observed ice lobe morphologies to infer modern basal shear stresses on Mars. Eventually, as we move toward more complex flow laws tied to ice physics, we anticipate that our results will show solutions to observed glacier plan view forms and surface profiles that are at least roughly consistent with ice behavior under today's climate and average geothermal environment and with available constraints on possible ice flow speeds deduced from geology.
Banks Maria Elaine
Pelletier J.
No associations
LandOfFree
Forward Modeling of the Topography and Flow of Ice on Mars to Infer Basal Shear Stress Conditions does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Forward Modeling of the Topography and Flow of Ice on Mars to Infer Basal Shear Stress Conditions, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Forward Modeling of the Topography and Flow of Ice on Mars to Infer Basal Shear Stress Conditions will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-961687