Hard rock landforms generate 130 km ice shelf channels through water focusing in basal corrugations
| Autor: | Jeofry, Hafeez, Ross, Neil, Le Brocq, Anne, Graham, Alastair G.C., Li, Jilu, Gogineni, Prasad, Morlighem, Mathieu, Jordan, Thomas, Siegert, Martin J. |
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| Jazyk: | angličtina |
| Rok vydání: | 2018 |
| Předmět: | |
| Zdroj: | Nature Communications, Vol 9, Iss 1, Pp 1-9 (2018) Jeofry, Hafeez; Ross, Neil; Le Brocq, Anne; Graham, Alastair GC; Li, Jilu; Gogineni, Prasad; et al.(2018). Hard rock landforms generate 130 km ice shelf channels through water focusing in basal corrugations.. Nature communications, 9(1), 4576. doi: 10.1038/s41467-018-06679-z. UC Irvine: Retrieved from: http://www.escholarship.org/uc/item/3572t71b Jeofry, H, Ross, N, Le Brocq, A, Graham, A, Li, J, Gogineni, P, Morlighem, M, Jordan, T & Siegert, M 2018, ' Hard rock landforms generate 130 km ice shelf channels through water focusing in basal corrugations ', Nature Communications, vol. 9, 4576 . https://doi.org/10.1038/s41467-018-06679-z Nature Communications |
| ISSN: | 2041-1723 |
| DOI: | 10.1038/s41467-018-06679-z. |
| Popis: | Satellite imagery reveals flowstripes on Foundation Ice Stream parallel to ice flow, and meandering features on the ice-shelf that cross-cut ice flow and are thought to be formed by water exiting a well-organised subglacial system. Here, ice-penetrating radar data show flow-parallel hard-bed landforms beneath the grounded ice, and channels incised upwards into the ice shelf beneath meandering surface channels. As the ice transitions to flotation, the ice shelf incorporates a corrugation resulting from the landforms. Radar reveals the presence of subglacial water alongside the landforms, indicating a well-organised drainage system in which water exits the ice sheet as a point source, mixes with cavity water and incises upwards into a corrugation peak, accentuating the corrugation downstream. Hard-bedded landforms influence both subglacial hydrology and ice-shelf structure and, as they are known to be widespread on formerly glaciated terrain, their influence on the ice-sheet-shelf transition could be more widespread than thought previously. Subglacial landforms, formed by glacial processes operating over long timescales, influence ice dynamics. Here, the authors show how mega-scale landforms at an Antarctic ice stream grounding zone modulate basal water flow, causing extensive channels in the ice shelf downstream that may impact its structure. |
| Databáze: | OpenAIRE |
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