Evidence for a dynamic grounding-line in outer Filchner Trough, Antarctica, until the early Holocene
Previous reconstructions of ice-sheet changes in Antarctica’s Weddell Sea sector since the Last Glacial Maximum (LGM) at 19–23 cal. (calibrated) kyr B.P. suffered from large uncertainties and were partly contradictory. As a consequence, the contribution of this sector to the LGM sea-level lowstand a...
Published in: | Geology |
---|---|
Main Authors: | , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Geological Society of America
2017
|
Subjects: | |
Online Access: | http://nora.nerc.ac.uk/id/eprint/517233/ https://nora.nerc.ac.uk/id/eprint/517233/1/Arndt%20et%20al.%20accepted.pdf https://pubs.geoscienceworld.org/gsa/geology/article-abstract/45/11/1035/516671/evidence-for-a-dynamic-grounding-line-in-outer?redirectedFrom=fulltext |
id |
ftnerc:oai:nora.nerc.ac.uk:517233 |
---|---|
record_format |
openpolar |
spelling |
ftnerc:oai:nora.nerc.ac.uk:517233 2023-05-15T13:49:34+02:00 Evidence for a dynamic grounding-line in outer Filchner Trough, Antarctica, until the early Holocene Arndt, Jan Erik Hillenbrand, Claus-Dieter Grobe, Hannes Kuhn, Gerhard Wacker, Lukas 2017-10 text http://nora.nerc.ac.uk/id/eprint/517233/ https://nora.nerc.ac.uk/id/eprint/517233/1/Arndt%20et%20al.%20accepted.pdf https://pubs.geoscienceworld.org/gsa/geology/article-abstract/45/11/1035/516671/evidence-for-a-dynamic-grounding-line-in-outer?redirectedFrom=fulltext en eng Geological Society of America https://nora.nerc.ac.uk/id/eprint/517233/1/Arndt%20et%20al.%20accepted.pdf Arndt, Jan Erik; Hillenbrand, Claus-Dieter orcid:0000-0003-0240-7317 Grobe, Hannes; Kuhn, Gerhard; Wacker, Lukas. 2017 Evidence for a dynamic grounding-line in outer Filchner Trough, Antarctica, until the early Holocene. Geology, 45 (11). 1035-1038. https://doi.org/10.1130/G39398.1 <https://doi.org/10.1130/G39398.1> Publication - Article PeerReviewed 2017 ftnerc https://doi.org/10.1130/G39398.1 2023-02-04T19:45:02Z Previous reconstructions of ice-sheet changes in Antarctica’s Weddell Sea sector since the Last Glacial Maximum (LGM) at 19–23 cal. (calibrated) kyr B.P. suffered from large uncertainties and were partly contradictory. As a consequence, the contribution of this sector to the LGM sea-level lowstand and post-LGM sea-level rise was unclear. Furthermore, whether and how precursor water masses for Antarctic Bottom Water (AABW) were formed in the Weddell Sea Embayment under glacial conditions is unknown, as this today requires the existence of the floating Filchner-Ronne Ice Shelf. Here we present new marine geophysical and marine geological data from the outer shelf section of the Filchner paleo–ice stream trough documenting that grounded ice had advanced onto and retreated from the outer shelf prior to 27.5 cal. kyr B.P., i.e., >4500 yr before the LGM. The data reveal the presence of a stacked grounding-zone wedge (GZW) just south of 75°30′S. This GZW was formed during two episodes of grounding-line re-advance onto the outer shelf after 11.8 cal. kyr B.P., with data further inshore implying paleo–ice stream retreat from the GZW location prior to 8.7 cal. kyr B.P. Our findings show that (1) ice-sheet buildup in the Weddell Sea sector made only limited contributions to the LGM sea-level lowstand, (2) ice-ocean interaction below an ice shelf in outer Filchner Trough could have contributed to AABW production at the LGM, and (3) numerical models need to take into account a highly dynamic ice-sheet behavior in regions of the West Antarctic Ice Sheet and East Antarctic Ice Sheet confluence. Article in Journal/Newspaper Antarc* Antarctic Antarctica Filchner Ronne Ice Shelf Filchner-Ronne Ice Shelf Ice Sheet Ice Shelf Ronne Ice Shelf Weddell Sea Natural Environment Research Council: NERC Open Research Archive Antarctic Weddell Sea West Antarctic Ice Sheet East Antarctic Ice Sheet Weddell Ronne Ice Shelf ENVELOPE(-61.000,-61.000,-78.500,-78.500) Filchner Trough ENVELOPE(-36.000,-36.000,-77.000,-77.000) Geology 45 11 1035 1038 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
English |
description |
Previous reconstructions of ice-sheet changes in Antarctica’s Weddell Sea sector since the Last Glacial Maximum (LGM) at 19–23 cal. (calibrated) kyr B.P. suffered from large uncertainties and were partly contradictory. As a consequence, the contribution of this sector to the LGM sea-level lowstand and post-LGM sea-level rise was unclear. Furthermore, whether and how precursor water masses for Antarctic Bottom Water (AABW) were formed in the Weddell Sea Embayment under glacial conditions is unknown, as this today requires the existence of the floating Filchner-Ronne Ice Shelf. Here we present new marine geophysical and marine geological data from the outer shelf section of the Filchner paleo–ice stream trough documenting that grounded ice had advanced onto and retreated from the outer shelf prior to 27.5 cal. kyr B.P., i.e., >4500 yr before the LGM. The data reveal the presence of a stacked grounding-zone wedge (GZW) just south of 75°30′S. This GZW was formed during two episodes of grounding-line re-advance onto the outer shelf after 11.8 cal. kyr B.P., with data further inshore implying paleo–ice stream retreat from the GZW location prior to 8.7 cal. kyr B.P. Our findings show that (1) ice-sheet buildup in the Weddell Sea sector made only limited contributions to the LGM sea-level lowstand, (2) ice-ocean interaction below an ice shelf in outer Filchner Trough could have contributed to AABW production at the LGM, and (3) numerical models need to take into account a highly dynamic ice-sheet behavior in regions of the West Antarctic Ice Sheet and East Antarctic Ice Sheet confluence. |
format |
Article in Journal/Newspaper |
author |
Arndt, Jan Erik Hillenbrand, Claus-Dieter Grobe, Hannes Kuhn, Gerhard Wacker, Lukas |
spellingShingle |
Arndt, Jan Erik Hillenbrand, Claus-Dieter Grobe, Hannes Kuhn, Gerhard Wacker, Lukas Evidence for a dynamic grounding-line in outer Filchner Trough, Antarctica, until the early Holocene |
author_facet |
Arndt, Jan Erik Hillenbrand, Claus-Dieter Grobe, Hannes Kuhn, Gerhard Wacker, Lukas |
author_sort |
Arndt, Jan Erik |
title |
Evidence for a dynamic grounding-line in outer Filchner Trough, Antarctica, until the early Holocene |
title_short |
Evidence for a dynamic grounding-line in outer Filchner Trough, Antarctica, until the early Holocene |
title_full |
Evidence for a dynamic grounding-line in outer Filchner Trough, Antarctica, until the early Holocene |
title_fullStr |
Evidence for a dynamic grounding-line in outer Filchner Trough, Antarctica, until the early Holocene |
title_full_unstemmed |
Evidence for a dynamic grounding-line in outer Filchner Trough, Antarctica, until the early Holocene |
title_sort |
evidence for a dynamic grounding-line in outer filchner trough, antarctica, until the early holocene |
publisher |
Geological Society of America |
publishDate |
2017 |
url |
http://nora.nerc.ac.uk/id/eprint/517233/ https://nora.nerc.ac.uk/id/eprint/517233/1/Arndt%20et%20al.%20accepted.pdf https://pubs.geoscienceworld.org/gsa/geology/article-abstract/45/11/1035/516671/evidence-for-a-dynamic-grounding-line-in-outer?redirectedFrom=fulltext |
long_lat |
ENVELOPE(-61.000,-61.000,-78.500,-78.500) ENVELOPE(-36.000,-36.000,-77.000,-77.000) |
geographic |
Antarctic Weddell Sea West Antarctic Ice Sheet East Antarctic Ice Sheet Weddell Ronne Ice Shelf Filchner Trough |
geographic_facet |
Antarctic Weddell Sea West Antarctic Ice Sheet East Antarctic Ice Sheet Weddell Ronne Ice Shelf Filchner Trough |
genre |
Antarc* Antarctic Antarctica Filchner Ronne Ice Shelf Filchner-Ronne Ice Shelf Ice Sheet Ice Shelf Ronne Ice Shelf Weddell Sea |
genre_facet |
Antarc* Antarctic Antarctica Filchner Ronne Ice Shelf Filchner-Ronne Ice Shelf Ice Sheet Ice Shelf Ronne Ice Shelf Weddell Sea |
op_relation |
https://nora.nerc.ac.uk/id/eprint/517233/1/Arndt%20et%20al.%20accepted.pdf Arndt, Jan Erik; Hillenbrand, Claus-Dieter orcid:0000-0003-0240-7317 Grobe, Hannes; Kuhn, Gerhard; Wacker, Lukas. 2017 Evidence for a dynamic grounding-line in outer Filchner Trough, Antarctica, until the early Holocene. Geology, 45 (11). 1035-1038. https://doi.org/10.1130/G39398.1 <https://doi.org/10.1130/G39398.1> |
op_doi |
https://doi.org/10.1130/G39398.1 |
container_title |
Geology |
container_volume |
45 |
container_issue |
11 |
container_start_page |
1035 |
op_container_end_page |
1038 |
_version_ |
1766251665004953600 |