Late Holocene ice-flow reconfiguration in the Weddell Sea sector of West Antarctica

• Published in: Quaternary Science Reviews
• Main Authors: Siegert, M, Ross, N, Corr, H, Kingslake, J, Hindmarsh, R
• Other Authors: Natural Environment Research Council (NERC), British Council (UK)
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2013
• Subjects: Science & Technology; Physical Sciences; Geography; Physical; Geosciences; Multidisciplinary; Physical Geography; Geology; Marine ice sheet; Internal layers; Ice rise; Ice sheet stability; GROUNDING-LINE RETREAT; LAST GLACIAL MAXIMUM; RONNE ICE; STREAM-C; SHEET; RADAR; SHELF; STABILITY; EMBAYMENT; CONSTRAINTS; 04 Earth Sciences; 21 History and Archaeology; Paleontology; Institute Ice Stream; Weddell; Weddell Sea; West Antarctica; Antarc*; Antarctica; Ice Sheet; Ice Stream C
• Online Access: http://hdl.handle.net/10044/1/72488; https://doi.org/10.1016/j.quascirev.2013.08.003

Here we report Late Holocene ice sheet and grounding-line changes to the Weddell Sea sector of West Antarctica. Internal radio-echo layering within the Bungenstock Ice Rise, which comprises very slow-flowing ice separating the fast-flowing Institute and Möller ice streams, reveals ice deformed by former enhanced flow, overlain by un-deformed ice. The ice-rise surface is traversed by surface lineations explicable as diffuse ice-flow generated stripes, which thus capture the direction of flow immediately prior to the creation of the ice rise. The arrangement of internal layers can be explained by adjustment to the flow path of the Institute Ice Stream, during either a phase of ice sheet retreat not longer than ∼4000 years ago or by wholesale expansion of the grounding-line from an already retreated situation not sooner than ∼400 years ago. Some combination of these events, involving uplift of the ice rise bed during ice stream retreat and reorganisation, is also possible. Whichever the case, the implication is that the ice sheet upstream of the Bungenstock Ice Rise, which currently grounds over a >1.5 km deep basin has been, and therefore may be, susceptible to significant change.