© International Glaciological Society The role of sedirn.ent transport in the rn.echanics of jokulhlaups
ABSTRACT. The classical theory of jokulhlaups used Rothlisberger's earlier theory of ice-channel drainage to describe the development of the Oood hydrograph. This theory has some drawbacks: the mechanism o [ initiation (breaking the seal) is opaque, the l\i[anning roughness coefficient is too l...
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ftciteseerx:oai:CiteSeerX.psu:10.1.1.303.3044 2023-05-15T16:50:12+02:00 © International Glaciological Society The role of sedirn.ent transport in the rn.echanics of jokulhlaups A. C. Fowler F. S. L. Ne The Pennsylvania State University CiteSeerX Archives application/pdf http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.303.3044 http://www.maths.ox.ac.uk/%7Efowler/papers/1996.3.pdf en eng http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.303.3044 http://www.maths.ox.ac.uk/%7Efowler/papers/1996.3.pdf Metadata may be used without restrictions as long as the oai identifier remains attached to it. http://www.maths.ox.ac.uk/%7Efowler/papers/1996.3.pdf text ftciteseerx 2016-01-07T22:10:20Z ABSTRACT. The classical theory of jokulhlaups used Rothlisberger's earlier theory of ice-channel drainage to describe the development of the Oood hydrograph. This theory has some drawbacks: the mechanism o [ initiation (breaking the seal) is opaque, the l\i[anning roughness coefficient is too large and the hydrographs can reveal a sudden switching from channel opening to channel closure which is not simulated by the model. In this paper, we examine these features by exploring a more detailed model, which takes into account the physics of sediment erosion and its effect on channel morphology. \Ve propose a theory in which channels need not be semicircular, but have shapes determined by a local balance between closure and melting, and in which erosion of the tunnel margins is taken into account; in particular, we deri\'e theoretical predictions for sediment discharge, and we also propose a mechanism whereby the pressure seal over the caldera rim at Grimsvotn in Vatnajokull, Iceland, can be broken when the lake-level water pressure is still some 6 bar below the maximum overburden ice pressure. 1. Text Iceland Unknown Grimsvotn ENVELOPE(-17.319,-17.319,64.416,64.416) |
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Unknown |
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ftciteseerx |
language |
English |
description |
ABSTRACT. The classical theory of jokulhlaups used Rothlisberger's earlier theory of ice-channel drainage to describe the development of the Oood hydrograph. This theory has some drawbacks: the mechanism o [ initiation (breaking the seal) is opaque, the l\i[anning roughness coefficient is too large and the hydrographs can reveal a sudden switching from channel opening to channel closure which is not simulated by the model. In this paper, we examine these features by exploring a more detailed model, which takes into account the physics of sediment erosion and its effect on channel morphology. \Ve propose a theory in which channels need not be semicircular, but have shapes determined by a local balance between closure and melting, and in which erosion of the tunnel margins is taken into account; in particular, we deri\'e theoretical predictions for sediment discharge, and we also propose a mechanism whereby the pressure seal over the caldera rim at Grimsvotn in Vatnajokull, Iceland, can be broken when the lake-level water pressure is still some 6 bar below the maximum overburden ice pressure. 1. |
author2 |
The Pennsylvania State University CiteSeerX Archives |
format |
Text |
author |
A. C. Fowler F. S. L. Ne |
spellingShingle |
A. C. Fowler F. S. L. Ne © International Glaciological Society The role of sedirn.ent transport in the rn.echanics of jokulhlaups |
author_facet |
A. C. Fowler F. S. L. Ne |
author_sort |
A. C. Fowler |
title |
© International Glaciological Society The role of sedirn.ent transport in the rn.echanics of jokulhlaups |
title_short |
© International Glaciological Society The role of sedirn.ent transport in the rn.echanics of jokulhlaups |
title_full |
© International Glaciological Society The role of sedirn.ent transport in the rn.echanics of jokulhlaups |
title_fullStr |
© International Glaciological Society The role of sedirn.ent transport in the rn.echanics of jokulhlaups |
title_full_unstemmed |
© International Glaciological Society The role of sedirn.ent transport in the rn.echanics of jokulhlaups |
title_sort |
© international glaciological society the role of sedirn.ent transport in the rn.echanics of jokulhlaups |
url |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.303.3044 http://www.maths.ox.ac.uk/%7Efowler/papers/1996.3.pdf |
long_lat |
ENVELOPE(-17.319,-17.319,64.416,64.416) |
geographic |
Grimsvotn |
geographic_facet |
Grimsvotn |
genre |
Iceland |
genre_facet |
Iceland |
op_source |
http://www.maths.ox.ac.uk/%7Efowler/papers/1996.3.pdf |
op_relation |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.303.3044 http://www.maths.ox.ac.uk/%7Efowler/papers/1996.3.pdf |
op_rights |
Metadata may be used without restrictions as long as the oai identifier remains attached to it. |
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1766040381382721536 |