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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Main Author: Adams, Vincent Clyde
Format: Text
Language:unknown
Published: LSU Digital Commons 2009
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Online Access: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
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spelling 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
institution Open Polar
collection LSU Digital Commons (Louisiana State University)
op_collection_id ftlouisianastuir
language unknown
topic Continental Shelf Record Ice Sheet Grounding Event
Antarctic Peninsula
Earth Sciences
spellingShingle 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
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