Reconstructions of Antarctic topography since the Eocene–Oligocene boundary.
Accurate models of past Antarctic ice sheet behaviour require realistic reconstructions of the evolution of bedrock topography. However, other than a preliminary attempt to reconstruct Antarctic topography at the Eocene–Oligocene boundary, the long-term evolution of Antarctica's subglacial topo...
Published in: | Palaeogeography, Palaeoclimatology, Palaeoecology |
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Elsevier B.V.
2019
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ftnerc:oai:nora.nerc.ac.uk:525116 2023-05-15T13:41:44+02:00 Reconstructions of Antarctic topography since the Eocene–Oligocene boundary. Paxman, Guy J.G. Jamieson, Stewart S.R. Hochmuth, Katharina Gohl, Karsten Bentley, Michael J. Leitchenkov, German Ferraccioli, Fausto 2019-12-01 text http://nora.nerc.ac.uk/id/eprint/525116/ https://nora.nerc.ac.uk/id/eprint/525116/1/1-s2.0-S0031018219304845-main.pdf https://www.sciencedirect.com/science/article/pii/S0031018219304845 en eng Elsevier B.V. https://nora.nerc.ac.uk/id/eprint/525116/1/1-s2.0-S0031018219304845-main.pdf Paxman, Guy J.G.; Jamieson, Stewart S.R.; Hochmuth, Katharina; Gohl, Karsten; Bentley, Michael J.; Leitchenkov, German; Ferraccioli, Fausto orcid:0000-0002-9347-4736 . 2019 Reconstructions of Antarctic topography since the Eocene–Oligocene boundary. Palaeogeography, Palaeoclimatology, Palaeoecology, 535, 109346. 17, pp. https://doi.org/10.1016/j.palaeo.2019.109346 <https://doi.org/10.1016/j.palaeo.2019.109346> cc_by_4 CC-BY Publication - Article PeerReviewed 2019 ftnerc https://doi.org/10.1016/j.palaeo.2019.109346 2023-02-04T19:49:15Z Accurate models of past Antarctic ice sheet behaviour require realistic reconstructions of the evolution of bedrock topography. However, other than a preliminary attempt to reconstruct Antarctic topography at the Eocene–Oligocene boundary, the long-term evolution of Antarctica's subglacial topography throughout its glacial history has not previously been quantified. Here, we derive new reconstructions of Antarctic topography for four key time slices in Antarctica's climate and glacial history: the Eocene–Oligocene boundary (ca. 34 Ma), the Oligocene–Miocene boundary (ca. 23 Ma), the mid-Miocene climate transition (ca. 14 Ma), and the mid-Pliocene warm period (ca. 3.5 Ma). To reconstruct past topography, we consider a series of processes including ice sheet loading, volcanism, thermal subsidence, horizontal plate motion, erosion, sedimentation and flexural isostatic adjustment, and validate our models where possible using onshore and offshore geological constraints. Our reconstructions show that the land area of Antarctica situated above sea level was ~25% larger at the Eocene–Oligocene boundary than at the present-day. Offshore sediment records and terrestrial constraints indicate that the incision of deep subglacial topographic troughs around the margin of East Antarctica occurred predominantly in the Oligocene and early Miocene, whereas in West Antarctica erosion and sedimentation rates accelerated after the mid-Miocene. Changes to the topography after the mid-Pliocene were comparatively minor. Our new palaeotopography reconstructions provide a critical boundary condition for models seeking to understand past behaviour of the Antarctic Ice Sheet, and have implications for estimating changes in global ice volume, temperature, and sea level across major Cenozoic climate transitions. Article in Journal/Newspaper Antarc* Antarctic Antarctica East Antarctica Ice Sheet West Antarctica Natural Environment Research Council: NERC Open Research Archive Antarctic The Antarctic East Antarctica West Antarctica Palaeogeography, Palaeoclimatology, Palaeoecology 535 109346 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
English |
description |
Accurate models of past Antarctic ice sheet behaviour require realistic reconstructions of the evolution of bedrock topography. However, other than a preliminary attempt to reconstruct Antarctic topography at the Eocene–Oligocene boundary, the long-term evolution of Antarctica's subglacial topography throughout its glacial history has not previously been quantified. Here, we derive new reconstructions of Antarctic topography for four key time slices in Antarctica's climate and glacial history: the Eocene–Oligocene boundary (ca. 34 Ma), the Oligocene–Miocene boundary (ca. 23 Ma), the mid-Miocene climate transition (ca. 14 Ma), and the mid-Pliocene warm period (ca. 3.5 Ma). To reconstruct past topography, we consider a series of processes including ice sheet loading, volcanism, thermal subsidence, horizontal plate motion, erosion, sedimentation and flexural isostatic adjustment, and validate our models where possible using onshore and offshore geological constraints. Our reconstructions show that the land area of Antarctica situated above sea level was ~25% larger at the Eocene–Oligocene boundary than at the present-day. Offshore sediment records and terrestrial constraints indicate that the incision of deep subglacial topographic troughs around the margin of East Antarctica occurred predominantly in the Oligocene and early Miocene, whereas in West Antarctica erosion and sedimentation rates accelerated after the mid-Miocene. Changes to the topography after the mid-Pliocene were comparatively minor. Our new palaeotopography reconstructions provide a critical boundary condition for models seeking to understand past behaviour of the Antarctic Ice Sheet, and have implications for estimating changes in global ice volume, temperature, and sea level across major Cenozoic climate transitions. |
format |
Article in Journal/Newspaper |
author |
Paxman, Guy J.G. Jamieson, Stewart S.R. Hochmuth, Katharina Gohl, Karsten Bentley, Michael J. Leitchenkov, German Ferraccioli, Fausto |
spellingShingle |
Paxman, Guy J.G. Jamieson, Stewart S.R. Hochmuth, Katharina Gohl, Karsten Bentley, Michael J. Leitchenkov, German Ferraccioli, Fausto Reconstructions of Antarctic topography since the Eocene–Oligocene boundary. |
author_facet |
Paxman, Guy J.G. Jamieson, Stewart S.R. Hochmuth, Katharina Gohl, Karsten Bentley, Michael J. Leitchenkov, German Ferraccioli, Fausto |
author_sort |
Paxman, Guy J.G. |
title |
Reconstructions of Antarctic topography since the Eocene–Oligocene boundary. |
title_short |
Reconstructions of Antarctic topography since the Eocene–Oligocene boundary. |
title_full |
Reconstructions of Antarctic topography since the Eocene–Oligocene boundary. |
title_fullStr |
Reconstructions of Antarctic topography since the Eocene–Oligocene boundary. |
title_full_unstemmed |
Reconstructions of Antarctic topography since the Eocene–Oligocene boundary. |
title_sort |
reconstructions of antarctic topography since the eocene–oligocene boundary. |
publisher |
Elsevier B.V. |
publishDate |
2019 |
url |
http://nora.nerc.ac.uk/id/eprint/525116/ https://nora.nerc.ac.uk/id/eprint/525116/1/1-s2.0-S0031018219304845-main.pdf https://www.sciencedirect.com/science/article/pii/S0031018219304845 |
geographic |
Antarctic The Antarctic East Antarctica West Antarctica |
geographic_facet |
Antarctic The Antarctic East Antarctica West Antarctica |
genre |
Antarc* Antarctic Antarctica East Antarctica Ice Sheet West Antarctica |
genre_facet |
Antarc* Antarctic Antarctica East Antarctica Ice Sheet West Antarctica |
op_relation |
https://nora.nerc.ac.uk/id/eprint/525116/1/1-s2.0-S0031018219304845-main.pdf Paxman, Guy J.G.; Jamieson, Stewart S.R.; Hochmuth, Katharina; Gohl, Karsten; Bentley, Michael J.; Leitchenkov, German; Ferraccioli, Fausto orcid:0000-0002-9347-4736 . 2019 Reconstructions of Antarctic topography since the Eocene–Oligocene boundary. Palaeogeography, Palaeoclimatology, Palaeoecology, 535, 109346. 17, pp. https://doi.org/10.1016/j.palaeo.2019.109346 <https://doi.org/10.1016/j.palaeo.2019.109346> |
op_rights |
cc_by_4 |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1016/j.palaeo.2019.109346 |
container_title |
Palaeogeography, Palaeoclimatology, Palaeoecology |
container_volume |
535 |
container_start_page |
109346 |
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1766155820886654976 |