Glacial geomorphology and cosmogenic 10Be and 26Al exposure ages in the northern Dufek Massif, Weddell Sea embayment, Antarctica
Hodgson, Dominic A.; Bentley, Michael J.; Schnabel, Christoph; Cziferszky, Andreas; Fretwell, Peter; Convey, Peter; Xu, Sheng. 2012 Glacial geomorphology and cosmogenic 10Be and 26Al exposure ages in the northern Dufek Massif, Weddell Sea embayment, Antarctica. Antarctic Science, 24 (4). 377-394. 10.1017/S0954102012000016Before downloading, please read NORA policies.
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We studied the glacial geomorphology and geochronology of two ice-free valleys in the Dufek Massif (Antarctic Specially Protected Area 119) providing new constraints on past ice sheet thickness in the Weddell Sea embayment. 10Be and 26Al cosmogenic surface exposure dating provided chronological control. Seven glacial stages are proposed. These include an alpine glaciation, with subsequent (mid- Miocene?) over-riding by a warm-based ice sheet. Subsequent advances are marked by a series of minor drift deposits at 760m altitude at .1 Ma, followed by at least two later ice sheet advances that are characterized by extensive drift sheet deposition. An advance of plateau ice field outlet glaciers from the south postdated these drift sheets. The most recent advance involved the cold-based expansion of the ice sheet from the north at the Last Glacial Maximum, or earlier, which deposited a series of bouldery moraines during its retreat. This suggests at most a relatively modest expansion of the ice sheet and outlet glaciers dominated by a lateral ice expansion of just 2–3 km and maintaining a thickness similar to that of the northern ice sheet front. These observations are consistent with other reports of modest ice sheet thickening around the Weddell Sea embayment during the Last Glacial Maximum.
|Programmes:||BAS Programmes > Polar Science for Planet Earth (2009 - ) > Chemistry and Past Climate|
|Additional Information:||Copyright 2012 Antarctic Science Ltd.|
|Additional Keywords:||deglaciation, glaciation, ice sheets, Pensacola Mountains, sea level, Transantarctic Mountains|
|Date made live:||09 Aug 2012 14:22|
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