Do laminated sediment-gravity-flow deposits on the Antarctic Peninsula continental shelf record ice sheet grounding events?
Barker and Camerlenghi (2002) proposed that drifts on the continental rise of the Antarctic Peninsula may record a high-resolution record of ice-sheet expansions on the adjacent continental shelf. In their view, laminated sediments were deposited during glacial periods, whereas during interglacial p...
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ftlouisianastuir:oai:digitalcommons.lsu.edu:gradschool_theses-4547 2023-06-11T04:06:51+02:00 Do laminated sediment-gravity-flow deposits on the Antarctic Peninsula continental shelf record ice sheet grounding events? Adams, Vincent Clyde 2009-01-01T08:00:00Z application/pdf https://digitalcommons.lsu.edu/gradschool_theses/3548 https://doi.org/10.31390/gradschool_theses.3548 https://digitalcommons.lsu.edu/context/gradschool_theses/article/4547/viewcontent/uc.pdf unknown LSU Digital Commons https://digitalcommons.lsu.edu/gradschool_theses/3548 doi:10.31390/gradschool_theses.3548 https://digitalcommons.lsu.edu/context/gradschool_theses/article/4547/viewcontent/uc.pdf LSU Master's Theses Continental Shelf Record Ice Sheet Grounding Event Antarctic Peninsula Earth Sciences text 2009 ftlouisianastuir https://doi.org/10.31390/gradschool_theses.3548 2023-05-28T19:05:14Z Barker and Camerlenghi (2002) proposed that drifts on the continental rise of the Antarctic Peninsula may record a high-resolution record of ice-sheet expansions on the adjacent continental shelf. In their view, laminated sediments were deposited during glacial periods, whereas during interglacial periods, sediment supply to drifts was negligible. As a consequence of low sediment supply, the tops of laminated sequences were bioturbated. Therefore, a bioturbated-laiminated couplet should represent a complete glacial cycle. Bioturbated and laminated (B-L) sediment couplets were compiled from cores at two drift sites obtained from Ocean Drilling Program (ODP) Leg 178 Sites 1095, 1096, and 1101. If the hypothesis is correct, then coeval sections should have the same number of B-L couplets given that glacial advance to the shelf edge is a major regional event. The comparison shows that the number of couplets in coeval section is similar for only 14% of the sections evaluated. The number of B-L couplets was also compared to the number of peak oscillations on δ18O records. The comparison of the B-L couplets to oscillations on the δ18O record shows that the two cycles agree for only 32% of the sections compared. The pervasive mismatch in the number of B-L couplets with coeval sections indicates that the couplets on the drifts cannot be simply associated with regional advance and retreat of grounded ice to the outer continental shelf of the Antarctic Peninsula. Bioturbation on the drifts and/or sediment delivery to the drift lacked sufficient spatial continuity to create a consistent record of glacial cycles. The mismatch with cycles on δ18O records likewise shows that B-L couplets on the Antarctic Peninsula cannot be directly related to global-scale ice-volume changes. Text Antarc* Antarctic Antarctic Peninsula Ice Sheet LSU Digital Commons (Louisiana State University) Antarctic The Antarctic Antarctic Peninsula |
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LSU Digital Commons (Louisiana State University) |
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Continental Shelf Record Ice Sheet Grounding Event Antarctic Peninsula Earth Sciences |
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Continental Shelf Record Ice Sheet Grounding Event Antarctic Peninsula Earth Sciences Adams, Vincent Clyde Do laminated sediment-gravity-flow deposits on the Antarctic Peninsula continental shelf record ice sheet grounding events? |
topic_facet |
Continental Shelf Record Ice Sheet Grounding Event Antarctic Peninsula Earth Sciences |
description |
Barker and Camerlenghi (2002) proposed that drifts on the continental rise of the Antarctic Peninsula may record a high-resolution record of ice-sheet expansions on the adjacent continental shelf. In their view, laminated sediments were deposited during glacial periods, whereas during interglacial periods, sediment supply to drifts was negligible. As a consequence of low sediment supply, the tops of laminated sequences were bioturbated. Therefore, a bioturbated-laiminated couplet should represent a complete glacial cycle. Bioturbated and laminated (B-L) sediment couplets were compiled from cores at two drift sites obtained from Ocean Drilling Program (ODP) Leg 178 Sites 1095, 1096, and 1101. If the hypothesis is correct, then coeval sections should have the same number of B-L couplets given that glacial advance to the shelf edge is a major regional event. The comparison shows that the number of couplets in coeval section is similar for only 14% of the sections evaluated. The number of B-L couplets was also compared to the number of peak oscillations on δ18O records. The comparison of the B-L couplets to oscillations on the δ18O record shows that the two cycles agree for only 32% of the sections compared. The pervasive mismatch in the number of B-L couplets with coeval sections indicates that the couplets on the drifts cannot be simply associated with regional advance and retreat of grounded ice to the outer continental shelf of the Antarctic Peninsula. Bioturbation on the drifts and/or sediment delivery to the drift lacked sufficient spatial continuity to create a consistent record of glacial cycles. The mismatch with cycles on δ18O records likewise shows that B-L couplets on the Antarctic Peninsula cannot be directly related to global-scale ice-volume changes. |
format |
Text |
author |
Adams, Vincent Clyde |
author_facet |
Adams, Vincent Clyde |
author_sort |
Adams, Vincent Clyde |
title |
Do laminated sediment-gravity-flow deposits on the Antarctic Peninsula continental shelf record ice sheet grounding events? |
title_short |
Do laminated sediment-gravity-flow deposits on the Antarctic Peninsula continental shelf record ice sheet grounding events? |
title_full |
Do laminated sediment-gravity-flow deposits on the Antarctic Peninsula continental shelf record ice sheet grounding events? |
title_fullStr |
Do laminated sediment-gravity-flow deposits on the Antarctic Peninsula continental shelf record ice sheet grounding events? |
title_full_unstemmed |
Do laminated sediment-gravity-flow deposits on the Antarctic Peninsula continental shelf record ice sheet grounding events? |
title_sort |
do laminated sediment-gravity-flow deposits on the antarctic peninsula continental shelf record ice sheet grounding events? |
publisher |
LSU Digital Commons |
publishDate |
2009 |
url |
https://digitalcommons.lsu.edu/gradschool_theses/3548 https://doi.org/10.31390/gradschool_theses.3548 https://digitalcommons.lsu.edu/context/gradschool_theses/article/4547/viewcontent/uc.pdf |
geographic |
Antarctic The Antarctic Antarctic Peninsula |
geographic_facet |
Antarctic The Antarctic Antarctic Peninsula |
genre |
Antarc* Antarctic Antarctic Peninsula Ice Sheet |
genre_facet |
Antarc* Antarctic Antarctic Peninsula Ice Sheet |
op_source |
LSU Master's Theses |
op_relation |
https://digitalcommons.lsu.edu/gradschool_theses/3548 doi:10.31390/gradschool_theses.3548 https://digitalcommons.lsu.edu/context/gradschool_theses/article/4547/viewcontent/uc.pdf |
op_doi |
https://doi.org/10.31390/gradschool_theses.3548 |
_version_ |
1768379030718906368 |