Glaciovolcanic evidence for a polythermal Neogene East Antarctic Ice Sheet
A paradigm has existed for more than 30 years that the basal thermal regime of the East Antarctic Ice Sheet in Victoria Land made a fundamental transition from wet-based to cold-based either at ca. 14 Ma or after ca. 2.5 Ma. The basal thermal regime is important because it determines the potential f...
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2014
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Online Access: | http://hdl.handle.net/11568/331867 https://doi.org/10.1130/G34787.1 http://geology.gsapubs.org/content/42/1/39.abstract |
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ftunivpisairis:oai:arpi.unipi.it:11568/331867 2024-04-14T08:04:07+00:00 Glaciovolcanic evidence for a polythermal Neogene East Antarctic Ice Sheet J. L. Smellie ROCCHI, SERGIO T. I. Wilch GEMELLI, MAURIZIO G. Di Vincenzo W. McIntosh N. Dunbar K. Panter A. Fargo J. L., Smellie Rocchi, Sergio T. I., Wilch Gemelli, Maurizio G., Di Vincenzo W., Mcintosh N., Dunbar K., Panter A., Fargo 2014 STAMPA http://hdl.handle.net/11568/331867 https://doi.org/10.1130/G34787.1 http://geology.gsapubs.org/content/42/1/39.abstract eng eng info:eu-repo/semantics/altIdentifier/wos/WOS:000333243200014 volume:42 issue:1 firstpage:39 lastpage:42 numberofpages:4 journal:GEOLOGY http://hdl.handle.net/11568/331867 doi:10.1130/G34787.1 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-84891639959 http://geology.gsapubs.org/content/42/1/39.abstract info:eu-repo/semantics/openAccess info:eu-repo/semantics/article 2014 ftunivpisairis https://doi.org/10.1130/G34787.1 2024-03-21T18:43:59Z A paradigm has existed for more than 30 years that the basal thermal regime of the East Antarctic Ice Sheet in Victoria Land made a fundamental transition from wet-based to cold-based either at ca. 14 Ma or after ca. 2.5 Ma. The basal thermal regime is important because it determines the potential for unstable behavior in an ice sheet. We have studied the environmental characteristics of subglacially erupted volcanic centers scattered along 800 km of the Ross Sea fl ank of the Transantarctic Mountains. The volcanoes preserve evidence for the coeval paleo-ice thicknesses and contain features diagnostic of both wet-based and cold-based ice conditions. By dating the sequences we are able to demonstrate that the basal thermal regime varied spatially and with time between ca. 12 Ma and present. It was polythermal overall and probably comprised a coarse temperature patchwork of frozen-bed and thawed-bed ice, similar to the East Antarctic Ice Sheet today. Thus, an important shift is required in the prevailing paradigm describing its temporal evolution. Article in Journal/Newspaper Antarc* Antarctic Ice Sheet Ross Sea Victoria Land ARPI - Archivio della Ricerca dell'Università di Pisa Antarctic Ross Sea Victoria Land East Antarctic Ice Sheet Transantarctic Mountains Geology 42 1 39 41 |
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Open Polar |
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ARPI - Archivio della Ricerca dell'Università di Pisa |
op_collection_id |
ftunivpisairis |
language |
English |
description |
A paradigm has existed for more than 30 years that the basal thermal regime of the East Antarctic Ice Sheet in Victoria Land made a fundamental transition from wet-based to cold-based either at ca. 14 Ma or after ca. 2.5 Ma. The basal thermal regime is important because it determines the potential for unstable behavior in an ice sheet. We have studied the environmental characteristics of subglacially erupted volcanic centers scattered along 800 km of the Ross Sea fl ank of the Transantarctic Mountains. The volcanoes preserve evidence for the coeval paleo-ice thicknesses and contain features diagnostic of both wet-based and cold-based ice conditions. By dating the sequences we are able to demonstrate that the basal thermal regime varied spatially and with time between ca. 12 Ma and present. It was polythermal overall and probably comprised a coarse temperature patchwork of frozen-bed and thawed-bed ice, similar to the East Antarctic Ice Sheet today. Thus, an important shift is required in the prevailing paradigm describing its temporal evolution. |
author2 |
J. L., Smellie Rocchi, Sergio T. I., Wilch Gemelli, Maurizio G., Di Vincenzo W., Mcintosh N., Dunbar K., Panter A., Fargo |
format |
Article in Journal/Newspaper |
author |
J. L. Smellie ROCCHI, SERGIO T. I. Wilch GEMELLI, MAURIZIO G. Di Vincenzo W. McIntosh N. Dunbar K. Panter A. Fargo |
spellingShingle |
J. L. Smellie ROCCHI, SERGIO T. I. Wilch GEMELLI, MAURIZIO G. Di Vincenzo W. McIntosh N. Dunbar K. Panter A. Fargo Glaciovolcanic evidence for a polythermal Neogene East Antarctic Ice Sheet |
author_facet |
J. L. Smellie ROCCHI, SERGIO T. I. Wilch GEMELLI, MAURIZIO G. Di Vincenzo W. McIntosh N. Dunbar K. Panter A. Fargo |
author_sort |
J. L. Smellie |
title |
Glaciovolcanic evidence for a polythermal Neogene East Antarctic Ice Sheet |
title_short |
Glaciovolcanic evidence for a polythermal Neogene East Antarctic Ice Sheet |
title_full |
Glaciovolcanic evidence for a polythermal Neogene East Antarctic Ice Sheet |
title_fullStr |
Glaciovolcanic evidence for a polythermal Neogene East Antarctic Ice Sheet |
title_full_unstemmed |
Glaciovolcanic evidence for a polythermal Neogene East Antarctic Ice Sheet |
title_sort |
glaciovolcanic evidence for a polythermal neogene east antarctic ice sheet |
publishDate |
2014 |
url |
http://hdl.handle.net/11568/331867 https://doi.org/10.1130/G34787.1 http://geology.gsapubs.org/content/42/1/39.abstract |
geographic |
Antarctic Ross Sea Victoria Land East Antarctic Ice Sheet Transantarctic Mountains |
geographic_facet |
Antarctic Ross Sea Victoria Land East Antarctic Ice Sheet Transantarctic Mountains |
genre |
Antarc* Antarctic Ice Sheet Ross Sea Victoria Land |
genre_facet |
Antarc* Antarctic Ice Sheet Ross Sea Victoria Land |
op_relation |
info:eu-repo/semantics/altIdentifier/wos/WOS:000333243200014 volume:42 issue:1 firstpage:39 lastpage:42 numberofpages:4 journal:GEOLOGY http://hdl.handle.net/11568/331867 doi:10.1130/G34787.1 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-84891639959 http://geology.gsapubs.org/content/42/1/39.abstract |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1130/G34787.1 |
container_title |
Geology |
container_volume |
42 |
container_issue |
1 |
container_start_page |
39 |
op_container_end_page |
41 |
_version_ |
1796300493361774592 |