Sedimentological Investigations of Paleo-Ice Sheet Dynamics in West Antarctica
Modern Pine Island and Thwaites Glaciers, which both drain into Pine Island Bay, are some of the fastest moving portions of the cryosphere and may be the most unstable ice streams in Antarctica. I examined over 133 cores to conduct a detailed sedimentological facies analysis. These data, augmented b...
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ftriceuniv:oai:scholarship.rice.edu:1911/71973 2023-05-15T13:24:17+02:00 Sedimentological Investigations of Paleo-Ice Sheet Dynamics in West Antarctica Kirshner, Alexandra Anderson, John B. Dasgupta, Rajdeep Hight, Christopher Gordon, Richard G. 2013-09-16T15:16:14Z application/pdf https://hdl.handle.net/1911/71973 eng eng Kirshner, Alexandra. "Sedimentological Investigations of Paleo-Ice Sheet Dynamics in West Antarctica." (2013) Diss., Rice University. https://hdl.handle.net/1911/71973 . https://hdl.handle.net/1911/71973 123456789/ETD-2013-05-241 Pine Island Bay Amundsen Sea Last glacial maximum Pine Island Glacier Subglacial meltwater Glacial history Glacial retreat Grounding line stability Ice stream Warm deep water SHALDRIL Antarctic Peninsula Micromorphology Thesis Text 2013 ftriceuniv 2022-08-09T20:46:56Z Modern Pine Island and Thwaites Glaciers, which both drain into Pine Island Bay, are some of the fastest moving portions of the cryosphere and may be the most unstable ice streams in Antarctica. I examined over 133 cores to conduct a detailed sedimentological facies analysis. These data, augmented by new radiocarbon and 210Pb dates, and bathymetric data, are used to reconstruct the post-LGM deglacial history of PIB and gain a better understanding of the causes of ice sheet retreat. My results record a clear retreat stratigraphy in PIB composed of, from top to base; terrigenous sandy silt (plumite), pebbly sandy mud (ice-proximal glacimarine), and till. Initial retreat from the outer-continental shelf began shortly after the LGM and before 16.4 k cal yr BP, in response to rising sea level. Bedforms in outer PIB document episodic retreat in the form of back-stepping grounding zone wedges and are associated with proximal glacimarine sediments. A sub-ice shelf facies is observed in central PIB that spans ∼12.3–10.6 k cal yr BP. Widespread impingement of warm water onto the continental shelf caused an abrupt change from sub-ice shelf sedimentation to distal glacimarine sedimentation dominated by dispersal of terrigenous silt between 7.8 and 7.0 k cal yr BP. The uppermost sediments in Pine Island Bay were hydrodynamically sorted by meltwater plumes. Inner Pine Island Bay contains several large basins that are linked by channels. The most recent release of sediment coincides with rapid retreat of the grounding line, and has an order of magnitude greater flux relative to the entire unit, indicating episodic sedimentation. This is the first identification of a meltwater-derived deposit in Antarctica and demonstrates that punctuated meltwater-intensive glacial retreat occurred at least three times throughout the Holocene in this region. Quartz sand grains were used to conduct an analysis of mode of transport for sediments in the Antarctic Peninsula region from the Eocene to present to record the onset of glaciation. ... Thesis Amundsen Sea Antarc* Antarctic Antarctic Peninsula Antarctica Ice Sheet Ice Shelf Pine Island Pine Island Bay Pine Island Glacier West Antarctica Rice University: Digital Scholarship Archive Amundsen Sea Antarctic Antarctic Peninsula Island Bay ENVELOPE(-109.085,-109.085,59.534,59.534) Pine Island Bay ENVELOPE(-102.000,-102.000,-74.750,-74.750) Pine Island Glacier ENVELOPE(-101.000,-101.000,-75.000,-75.000) The Antarctic West Antarctica |
institution |
Open Polar |
collection |
Rice University: Digital Scholarship Archive |
op_collection_id |
ftriceuniv |
language |
English |
topic |
Pine Island Bay Amundsen Sea Last glacial maximum Pine Island Glacier Subglacial meltwater Glacial history Glacial retreat Grounding line stability Ice stream Warm deep water SHALDRIL Antarctic Peninsula Micromorphology |
spellingShingle |
Pine Island Bay Amundsen Sea Last glacial maximum Pine Island Glacier Subglacial meltwater Glacial history Glacial retreat Grounding line stability Ice stream Warm deep water SHALDRIL Antarctic Peninsula Micromorphology Kirshner, Alexandra Sedimentological Investigations of Paleo-Ice Sheet Dynamics in West Antarctica |
topic_facet |
Pine Island Bay Amundsen Sea Last glacial maximum Pine Island Glacier Subglacial meltwater Glacial history Glacial retreat Grounding line stability Ice stream Warm deep water SHALDRIL Antarctic Peninsula Micromorphology |
description |
Modern Pine Island and Thwaites Glaciers, which both drain into Pine Island Bay, are some of the fastest moving portions of the cryosphere and may be the most unstable ice streams in Antarctica. I examined over 133 cores to conduct a detailed sedimentological facies analysis. These data, augmented by new radiocarbon and 210Pb dates, and bathymetric data, are used to reconstruct the post-LGM deglacial history of PIB and gain a better understanding of the causes of ice sheet retreat. My results record a clear retreat stratigraphy in PIB composed of, from top to base; terrigenous sandy silt (plumite), pebbly sandy mud (ice-proximal glacimarine), and till. Initial retreat from the outer-continental shelf began shortly after the LGM and before 16.4 k cal yr BP, in response to rising sea level. Bedforms in outer PIB document episodic retreat in the form of back-stepping grounding zone wedges and are associated with proximal glacimarine sediments. A sub-ice shelf facies is observed in central PIB that spans ∼12.3–10.6 k cal yr BP. Widespread impingement of warm water onto the continental shelf caused an abrupt change from sub-ice shelf sedimentation to distal glacimarine sedimentation dominated by dispersal of terrigenous silt between 7.8 and 7.0 k cal yr BP. The uppermost sediments in Pine Island Bay were hydrodynamically sorted by meltwater plumes. Inner Pine Island Bay contains several large basins that are linked by channels. The most recent release of sediment coincides with rapid retreat of the grounding line, and has an order of magnitude greater flux relative to the entire unit, indicating episodic sedimentation. This is the first identification of a meltwater-derived deposit in Antarctica and demonstrates that punctuated meltwater-intensive glacial retreat occurred at least three times throughout the Holocene in this region. Quartz sand grains were used to conduct an analysis of mode of transport for sediments in the Antarctic Peninsula region from the Eocene to present to record the onset of glaciation. ... |
author2 |
Anderson, John B. Dasgupta, Rajdeep Hight, Christopher Gordon, Richard G. |
format |
Thesis |
author |
Kirshner, Alexandra |
author_facet |
Kirshner, Alexandra |
author_sort |
Kirshner, Alexandra |
title |
Sedimentological Investigations of Paleo-Ice Sheet Dynamics in West Antarctica |
title_short |
Sedimentological Investigations of Paleo-Ice Sheet Dynamics in West Antarctica |
title_full |
Sedimentological Investigations of Paleo-Ice Sheet Dynamics in West Antarctica |
title_fullStr |
Sedimentological Investigations of Paleo-Ice Sheet Dynamics in West Antarctica |
title_full_unstemmed |
Sedimentological Investigations of Paleo-Ice Sheet Dynamics in West Antarctica |
title_sort |
sedimentological investigations of paleo-ice sheet dynamics in west antarctica |
publishDate |
2013 |
url |
https://hdl.handle.net/1911/71973 |
long_lat |
ENVELOPE(-109.085,-109.085,59.534,59.534) ENVELOPE(-102.000,-102.000,-74.750,-74.750) ENVELOPE(-101.000,-101.000,-75.000,-75.000) |
geographic |
Amundsen Sea Antarctic Antarctic Peninsula Island Bay Pine Island Bay Pine Island Glacier The Antarctic West Antarctica |
geographic_facet |
Amundsen Sea Antarctic Antarctic Peninsula Island Bay Pine Island Bay Pine Island Glacier The Antarctic West Antarctica |
genre |
Amundsen Sea Antarc* Antarctic Antarctic Peninsula Antarctica Ice Sheet Ice Shelf Pine Island Pine Island Bay Pine Island Glacier West Antarctica |
genre_facet |
Amundsen Sea Antarc* Antarctic Antarctic Peninsula Antarctica Ice Sheet Ice Shelf Pine Island Pine Island Bay Pine Island Glacier West Antarctica |
op_relation |
Kirshner, Alexandra. "Sedimentological Investigations of Paleo-Ice Sheet Dynamics in West Antarctica." (2013) Diss., Rice University. https://hdl.handle.net/1911/71973 . https://hdl.handle.net/1911/71973 123456789/ETD-2013-05-241 |
_version_ |
1766378551833001984 |