Late Pleistocene Interactions of East and West Antarctic Ice-Flow Regimes: Evidence from the McMurdo Ice Shelf
We present new interpretations of deglaciation in McMurdo Sound and the western Ross Sea, with observationally based reconstructions of interactions between East and West Antarctic ice at the last glacial maximum (LGM), 16 000, 12 000, 8000 and 4000 sp. At the LGM? East Antarctic ice from Mulock Gla...
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ftmaineuniv:oai:digitalcommons.library.umaine.edu:ers_facpub-1055 2024-09-15T17:40:57+00:00 Late Pleistocene Interactions of East and West Antarctic Ice-Flow Regimes: Evidence from the McMurdo Ice Shelf Kellogg, Thomas B. Hughes, Terence J. Kellogg, Davida E. 1996-01-01T08:00:00Z application/pdf https://digitalcommons.library.umaine.edu/ers_facpub/56 https://digitalcommons.library.umaine.edu/context/ers_facpub/article/1055/viewcontent/hughes_42.142.486.pdf unknown DigitalCommons@UMaine https://digitalcommons.library.umaine.edu/ers_facpub/56 https://digitalcommons.library.umaine.edu/context/ers_facpub/article/1055/viewcontent/hughes_42.142.486.pdf This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. In addition, no permission is required from the rights-holder(s) for educational uses. For other uses, you need to obtain permission from the rights-holder(s). Earth Science Faculty Scholarship Earth Sciences text 1996 ftmaineuniv 2024-07-24T05:38:40Z We present new interpretations of deglaciation in McMurdo Sound and the western Ross Sea, with observationally based reconstructions of interactions between East and West Antarctic ice at the last glacial maximum (LGM), 16 000, 12 000, 8000 and 4000 sp. At the LGM? East Antarctic ice from Mulock Glacier split, one branch turned westward south of Ross Island but the other branch rounded Ross Island before flowing southwest into McMurdo Sound. This flow regime, constrained by an ice saddle north of Ross Island, is consistent with the reconstruction of Stuiver and others (1981a). After the LGM, grounding-line retreat was most rapid in areas with greatest water depth, especially along the Victoria Land coast. By 12 000 sp, the ice-now regime in McMurdo Sound changed to through-flowing Mulock Glacier ice, with lesser contributions from Koettlitz, Blue and Ferrar Glaciers, because the former ice saddle north of Ross Island was replaced by a dome. The modern flew regime was established similar to 4000 BP. Ice derived from high elevations on the Polar Plateau but now stranded on the McMurdo Ice Shelf, and the pattern of the Transantarctic Mountains erratics support our reconstructions of Mulock Glacier ice rounding Minna Bluff but with all ice from Skelton Glacier ablating south of the bluff. They are inconsistent with Drewry's (1979) LGM reconstruction that includes Skelton Glacier ice in the McMurdo-Sound through-flow. Drewry's (1979) model closely approximates our results for 12 000-4000 BP. Ice-sheet modeling holds promise for determining whether deglaciation proceeded by grounding-line retreat of an ice sheet that was largely stagnant, because it never approached equilibrium flowline profiles after the Ross Ice Shelf, grounded, or of a dynamic ice sheet with flowline profiles kept low by active ice streams that extended northward from present-day outlet glaciers after the Ross Ice Shelf grounded. Text Antarc* Antarctic Ice Sheet Ice Shelf McMurdo Ice Shelf McMurdo Sound Mulock Glacier Ross Ice Shelf Ross Island Ross Sea Skelton Glacier Victoria Land The University of Maine: DigitalCommons@UMaine |
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The University of Maine: DigitalCommons@UMaine |
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ftmaineuniv |
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unknown |
topic |
Earth Sciences |
spellingShingle |
Earth Sciences Kellogg, Thomas B. Hughes, Terence J. Kellogg, Davida E. Late Pleistocene Interactions of East and West Antarctic Ice-Flow Regimes: Evidence from the McMurdo Ice Shelf |
topic_facet |
Earth Sciences |
description |
We present new interpretations of deglaciation in McMurdo Sound and the western Ross Sea, with observationally based reconstructions of interactions between East and West Antarctic ice at the last glacial maximum (LGM), 16 000, 12 000, 8000 and 4000 sp. At the LGM? East Antarctic ice from Mulock Glacier split, one branch turned westward south of Ross Island but the other branch rounded Ross Island before flowing southwest into McMurdo Sound. This flow regime, constrained by an ice saddle north of Ross Island, is consistent with the reconstruction of Stuiver and others (1981a). After the LGM, grounding-line retreat was most rapid in areas with greatest water depth, especially along the Victoria Land coast. By 12 000 sp, the ice-now regime in McMurdo Sound changed to through-flowing Mulock Glacier ice, with lesser contributions from Koettlitz, Blue and Ferrar Glaciers, because the former ice saddle north of Ross Island was replaced by a dome. The modern flew regime was established similar to 4000 BP. Ice derived from high elevations on the Polar Plateau but now stranded on the McMurdo Ice Shelf, and the pattern of the Transantarctic Mountains erratics support our reconstructions of Mulock Glacier ice rounding Minna Bluff but with all ice from Skelton Glacier ablating south of the bluff. They are inconsistent with Drewry's (1979) LGM reconstruction that includes Skelton Glacier ice in the McMurdo-Sound through-flow. Drewry's (1979) model closely approximates our results for 12 000-4000 BP. Ice-sheet modeling holds promise for determining whether deglaciation proceeded by grounding-line retreat of an ice sheet that was largely stagnant, because it never approached equilibrium flowline profiles after the Ross Ice Shelf, grounded, or of a dynamic ice sheet with flowline profiles kept low by active ice streams that extended northward from present-day outlet glaciers after the Ross Ice Shelf grounded. |
format |
Text |
author |
Kellogg, Thomas B. Hughes, Terence J. Kellogg, Davida E. |
author_facet |
Kellogg, Thomas B. Hughes, Terence J. Kellogg, Davida E. |
author_sort |
Kellogg, Thomas B. |
title |
Late Pleistocene Interactions of East and West Antarctic Ice-Flow Regimes: Evidence from the McMurdo Ice Shelf |
title_short |
Late Pleistocene Interactions of East and West Antarctic Ice-Flow Regimes: Evidence from the McMurdo Ice Shelf |
title_full |
Late Pleistocene Interactions of East and West Antarctic Ice-Flow Regimes: Evidence from the McMurdo Ice Shelf |
title_fullStr |
Late Pleistocene Interactions of East and West Antarctic Ice-Flow Regimes: Evidence from the McMurdo Ice Shelf |
title_full_unstemmed |
Late Pleistocene Interactions of East and West Antarctic Ice-Flow Regimes: Evidence from the McMurdo Ice Shelf |
title_sort |
late pleistocene interactions of east and west antarctic ice-flow regimes: evidence from the mcmurdo ice shelf |
publisher |
DigitalCommons@UMaine |
publishDate |
1996 |
url |
https://digitalcommons.library.umaine.edu/ers_facpub/56 https://digitalcommons.library.umaine.edu/context/ers_facpub/article/1055/viewcontent/hughes_42.142.486.pdf |
genre |
Antarc* Antarctic Ice Sheet Ice Shelf McMurdo Ice Shelf McMurdo Sound Mulock Glacier Ross Ice Shelf Ross Island Ross Sea Skelton Glacier Victoria Land |
genre_facet |
Antarc* Antarctic Ice Sheet Ice Shelf McMurdo Ice Shelf McMurdo Sound Mulock Glacier Ross Ice Shelf Ross Island Ross Sea Skelton Glacier Victoria Land |
op_source |
Earth Science Faculty Scholarship |
op_relation |
https://digitalcommons.library.umaine.edu/ers_facpub/56 https://digitalcommons.library.umaine.edu/context/ers_facpub/article/1055/viewcontent/hughes_42.142.486.pdf |
op_rights |
This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. In addition, no permission is required from the rights-holder(s) for educational uses. For other uses, you need to obtain permission from the rights-holder(s). |
_version_ |
1810487015514308608 |