Supraglacial debris along the front of the Larsen-A Ice Shelf, Antarctic Peninsula
Semi-continuous, linear accumulations of poorly-sorted debris are present on the surface of the remnant Larsen-A Ice Shelf, Antarctic Peninsula. These accumulations form a complex of debris bands extending parallel to the front of the ice shelf for several kilometres. Landsat imagery shows that the...
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Cambridge University Press (CUP)
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Online Access: | http://dx.doi.org/10.1017/s0954102003001615 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0954102003001615 |
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crcambridgeupr:10.1017/s0954102003001615 2024-09-15T17:46:56+00:00 Supraglacial debris along the front of the Larsen-A Ice Shelf, Antarctic Peninsula EVANS, JEFFREY COFAIGH, COLM Ó 2003 http://dx.doi.org/10.1017/s0954102003001615 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0954102003001615 en eng Cambridge University Press (CUP) https://www.cambridge.org/core/terms Antarctic Science volume 15, issue 4, page 503-506 ISSN 0954-1020 1365-2079 journal-article 2003 crcambridgeupr https://doi.org/10.1017/s0954102003001615 2024-08-14T04:04:03Z Semi-continuous, linear accumulations of poorly-sorted debris are present on the surface of the remnant Larsen-A Ice Shelf, Antarctic Peninsula. These accumulations form a complex of debris bands extending parallel to the front of the ice shelf for several kilometres. Landsat imagery shows that the debris bands originated as lateral moraines along the Nordenskjöld Coast. Almost 80% of clasts sampled from these debris accumulations have shape/roundness characteristics consistent with glacier transport in the zone of basal traction. Angular and very angular clasts account for 15% and 22% of clasts in the pebble- and cobble/boulder-sized fractions, respectively, and originated by rockfall from valley/nunatak sides, with subsequent passive glacier transportation. Lithological analysis indicates that the debris is derived locally from the Nordenskjöld Coast, Cape Fairweather region and interior of the Antarctic Peninsula. Episodic melt-out and resedimentation of this debris from the front of the ice shelf would deliver pulses of coarse-grained sediment to the sea floor. Therefore, coarse-grained debris can also be released along the calving margin of small polar ice shelves fringing mountainous terrain, and could potentially be confused with sediment deposited at the grounding line of Antarctic ice-shelves. Sedimentological criteria to differentiate between these environments are proposed in this paper. Article in Journal/Newspaper Antarc* Antarctic Antarctic Peninsula Antarctic Science Ice Shelf Ice Shelves Cambridge University Press Antarctic Science 15 4 503 506 |
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Open Polar |
collection |
Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
description |
Semi-continuous, linear accumulations of poorly-sorted debris are present on the surface of the remnant Larsen-A Ice Shelf, Antarctic Peninsula. These accumulations form a complex of debris bands extending parallel to the front of the ice shelf for several kilometres. Landsat imagery shows that the debris bands originated as lateral moraines along the Nordenskjöld Coast. Almost 80% of clasts sampled from these debris accumulations have shape/roundness characteristics consistent with glacier transport in the zone of basal traction. Angular and very angular clasts account for 15% and 22% of clasts in the pebble- and cobble/boulder-sized fractions, respectively, and originated by rockfall from valley/nunatak sides, with subsequent passive glacier transportation. Lithological analysis indicates that the debris is derived locally from the Nordenskjöld Coast, Cape Fairweather region and interior of the Antarctic Peninsula. Episodic melt-out and resedimentation of this debris from the front of the ice shelf would deliver pulses of coarse-grained sediment to the sea floor. Therefore, coarse-grained debris can also be released along the calving margin of small polar ice shelves fringing mountainous terrain, and could potentially be confused with sediment deposited at the grounding line of Antarctic ice-shelves. Sedimentological criteria to differentiate between these environments are proposed in this paper. |
format |
Article in Journal/Newspaper |
author |
EVANS, JEFFREY COFAIGH, COLM Ó |
spellingShingle |
EVANS, JEFFREY COFAIGH, COLM Ó Supraglacial debris along the front of the Larsen-A Ice Shelf, Antarctic Peninsula |
author_facet |
EVANS, JEFFREY COFAIGH, COLM Ó |
author_sort |
EVANS, JEFFREY |
title |
Supraglacial debris along the front of the Larsen-A Ice Shelf, Antarctic Peninsula |
title_short |
Supraglacial debris along the front of the Larsen-A Ice Shelf, Antarctic Peninsula |
title_full |
Supraglacial debris along the front of the Larsen-A Ice Shelf, Antarctic Peninsula |
title_fullStr |
Supraglacial debris along the front of the Larsen-A Ice Shelf, Antarctic Peninsula |
title_full_unstemmed |
Supraglacial debris along the front of the Larsen-A Ice Shelf, Antarctic Peninsula |
title_sort |
supraglacial debris along the front of the larsen-a ice shelf, antarctic peninsula |
publisher |
Cambridge University Press (CUP) |
publishDate |
2003 |
url |
http://dx.doi.org/10.1017/s0954102003001615 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0954102003001615 |
genre |
Antarc* Antarctic Antarctic Peninsula Antarctic Science Ice Shelf Ice Shelves |
genre_facet |
Antarc* Antarctic Antarctic Peninsula Antarctic Science Ice Shelf Ice Shelves |
op_source |
Antarctic Science volume 15, issue 4, page 503-506 ISSN 0954-1020 1365-2079 |
op_rights |
https://www.cambridge.org/core/terms |
op_doi |
https://doi.org/10.1017/s0954102003001615 |
container_title |
Antarctic Science |
container_volume |
15 |
container_issue |
4 |
container_start_page |
503 |
op_container_end_page |
506 |
_version_ |
1810495382670540800 |