Prosiectau fesul blwyddyn
Crynodeb
Longitudinal ice-surface structures in the Antarctic Ice Sheet can be traced continuously down-ice for distances of up to 1200 km. A map of the distribution of ~ 3600 of these features, compiled from satellite images, shows that they mirror the location of fast-flowing glaciers and ice streams that are dominated by basal sliding rates above tens of metres per annum and are strongly guided by subglacial topography. Longitudinal ice-surface structures dominate regions of converging flow, where ice flow is subject to non-coaxial strain and simple shear. They can be traced continuously through crevasse fields and through blue-ice areas, indicating that they represent the surface manifestation of a three-dimensional structure, interpreted as foliation. Flow lines are linear and undeformed for all major flow units described here in the Antarctic Ice Sheet except for the Kamb Ice Stream and the Institute and Möller Ice Stream areas, where areas of flow perturbation are evident. Parcels of ice along individual flow paths on the Lambert Glacier, Recovery Glacier, Byrd Glacier and Pine Island Glacier may reside in the glacier system for ~ 2500 to 18 500 years. Although it is unclear how long it takes for these features to form and decay, we infer that the major ice-flow configuration of the ice sheet may have remained largely unchanged for the last few hundred years, and possibly even longer. This conclusion has implications for our understanding of the long-term landscape evolution of Antarctica, including large-scale patterns of glacial erosion and deposition.
Iaith wreiddiol | Saesneg |
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Tudalennau (o-i) | 239-249 |
Nifer y tudalennau | 11 |
Cyfnodolyn | Earth Surface Dynamics |
Cyfrol | 3 |
Dynodwyr Gwrthrych Digidol (DOIs) | |
Statws | Cyhoeddwyd - 01 Maw 2015 |
Ôl bys
Gweld gwybodaeth am bynciau ymchwil 'Origin and dynamic significance of longitudinal structures (“flow stripes”) in the Antarctic Ice Sheet'. Gyda’i gilydd, maen nhw’n ffurfio ôl bys unigryw.Traethodau Ymchwil Myfyriwr
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Origins of foliations and related phenomena in valley glaciers and ice sheets
Jennings, S. J. A. (Awdur), Glasser, N. (Goruchwylydd), Hubbard, B. (Goruchwylydd) & Hambrey, M. (Goruchwylydd), 17 Chwef 2017Traethawd ymchwil myfyriwr: Traethawd Ymchwil Doethurol › Doethur mewn Athroniaeth
Ffeil
Prosiectau
- 1 Wedi Gorffen
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Investigation into the structural characteristics of valley glacier foliations and subsequent comparison to large-scale ice sheet flowlines
Jennings, S. J. A. (Prif Ymchwilydd)
03 Hyd 2012 → 02 Ebr 2016
Prosiect: Ymchwil a ariannwyd yn allanol