Ice flow across a warm-based/cold-based transition at a glacier margin

dc.contributor.author Moore, Peter
dc.contributor.author Moore, Peter
dc.contributor.author Iverson, Neal
dc.contributor.author Cohen, Denis
dc.contributor.author Iverson, Neal
dc.contributor.department Natural Resource Ecology and Management
dc.date 2018-02-15T23:35:43.000
dc.date.accessioned 2020-06-30T06:14:00Z
dc.date.available 2020-06-30T06:14:00Z
dc.date.copyright Thu Jan 01 00:00:00 UTC 2009
dc.date.embargo 2015-03-12
dc.date.issued 2009-10-01
dc.description.abstract <p>Where polythermal glaciers have frozen margins that buttress otherwise temperate-based sliding ice, longitudinal compression can strongly influence ice flow trajectory, and consequently sediment transport paths. Past efforts to model flow in the vicinity of a basal thermal transition (BTT) have generally relied on simplified boundary conditions or rheological idealizations, making these model results difficult to apply to real glacier termini. Herein, we present results of numerical simulations using a power-law rheology and with boundary conditions that better represent the frozen margin. Model results indicate that a transition to a non-sliding frozen margin causes a decline in surface velocity made possible by upward ice flow, implying either enhanced ablation for steady-state simulations or the formation of a surface bulge. Permitting ice loss by ablation combined with realistic treatment of basal slip conditions subdues basal stress concentrations and thereby inhibits development of structural discontinuities such as thrust faults. Upward ice flow is accommodated by vertical extension upglacier of the BTT. This strain regime can potentially account for key structural features in polythermal glacier termini without appealing to thrusting.</p>
dc.description.comments <p>This is a manuscript of an article from <em>Journal of Glaciology</em> 50 (2009): 1, doi.: <a href="http://dx.doi.org/10.3189/172756409789624319" target="_blank">10.3189/172756409789624319</a>. Posted with permission.</p>
dc.format.mimetype application/pdf
dc.identifier archive/lib.dr.iastate.edu/nrem_pubs/92/
dc.identifier.articleid 1090
dc.identifier.contextkey 6824980
dc.identifier.s3bucket isulib-bepress-aws-west
dc.identifier.submissionpath nrem_pubs/92
dc.identifier.uri https://dr.lib.iastate.edu/handle/20.500.12876/56438
dc.language.iso en
dc.source.bitstream archive/lib.dr.iastate.edu/nrem_pubs/92/2009_Moore_IceFlowAcross.pdf|||Sat Jan 15 02:29:36 UTC 2022
dc.source.uri 10.3189/172756409789624319
dc.subject.disciplines Glaciology
dc.subject.disciplines Natural Resources Management and Policy
dc.subject.keywords polythermal glaciers
dc.subject.keywords sediment transport paths
dc.subject.keywords vertical extension upglacier
dc.subject.keywords thrust
dc.title Ice flow across a warm-based/cold-based transition at a glacier margin
dc.type article
dc.type.genre article
dspace.entity.type Publication
relation.isAuthorOfPublication 521761e7-5d03-44f5-acfd-d1ac32acc8bd
relation.isAuthorOfPublication 8f9617fd-0ee4-4473-b7bb-ef722542e676
relation.isOrgUnitOfPublication e87b7b9d-30ea-4978-9fb9-def61b4010ae
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