Flexural controls on late Neogene basin evolution in southern McMurdo Sound, Antarctica
The basins of southern McMurdo Sound have evolved under the influence of lithospheric flexure induced by the loads of the Erebus Volcanic Province. To characterise these basins, it is important to investigate the lithosphere's flexural properties, and estimate their influence on basin architect...
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ftnerc:oai:nora.nerc.ac.uk:20845 2024-02-11T09:58:26+01:00 Flexural controls on late Neogene basin evolution in southern McMurdo Sound, Antarctica Aitken, Alan R.A. Wilson, Gary S. Jordan, Thomas Tinto, Kirsty Blakemore, Hamish 2012-12-18 http://nora.nerc.ac.uk/id/eprint/20845/ https://doi.org/10.1016/j.gloplacha.2011.08.003 unknown Elsevier Aitken, Alan R.A.; Wilson, Gary S.; Jordan, Thomas orcid:0000-0003-2780-1986 Tinto, Kirsty; Blakemore, Hamish. 2012 Flexural controls on late Neogene basin evolution in southern McMurdo Sound, Antarctica. Global and Planetary Change, 80-81. 99-112. https://doi.org/10.1016/j.gloplacha.2011.08.003 <https://doi.org/10.1016/j.gloplacha.2011.08.003> Earth Sciences Publication - Article PeerReviewed 2012 ftnerc https://doi.org/10.1016/j.gloplacha.2011.08.003 2024-01-26T00:03:20Z The basins of southern McMurdo Sound have evolved under the influence of lithospheric flexure induced by the loads of the Erebus Volcanic Province. To characterise these basins, it is important to investigate the lithosphere's flexural properties, and estimate their influence on basin architecture and evolution. Seismic and gravity data are used to constrain 3D forward modelling of the progressive development of accommodation space within the flexural basins. Elastic plate flexure was calculated for a range of effective elastic thicknesses (Te) from 0.5 to 25 km using a spectral method. Models with low, but nonzero, Te values (2 km < Te < 5 km) produce the best fit to the gravity data, although uncertainty is high due to inaccuracies in the Digital Elevation Model. The slopes of flexural horizons revealed in seismic reflection lines are consistent with this, indicating a Te of 2 km to 5 km, although the depths to these horizons are not consistent, perhaps due to a northwards slope, or step, in the pre-flexural surface. These results indicate that the lithospheric strength of southern McMurdo Sound is significantly less than estimates of the regional average (Te ~ 20 km). This low strength may reflect the weakening effects of the Terror Rift, and perhaps also the Discovery Accommodation Zone, a region of major transverse faulting. A low Te model (Te = 3) for southern McMurdo Sound predicts the development of two discrete flexural depressions, each 2–2.5 km deep. The predicted stratigraphy of the northern basin reflects flexure due to Ross Island, predominantly erupted since ca. 1.8 Ma. The predicted stratigraphy of the southern basin reflects more gradual flexure from ca. 10 Ma to ca. 2 Ma, due to the more dispersed volcanoes of the Discovery subprovince. Collectively, these two basins have the potential to preserve a remarkable stratigraphic record of Antarctic climate change through the late Neogene. Article in Journal/Newspaper Antarc* Antarctic Antarctica McMurdo Sound Ross Island Natural Environment Research Council: NERC Open Research Archive Antarctic McMurdo Sound Ross Island Global and Planetary Change 80-81 99 112 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
unknown |
topic |
Earth Sciences |
spellingShingle |
Earth Sciences Aitken, Alan R.A. Wilson, Gary S. Jordan, Thomas Tinto, Kirsty Blakemore, Hamish Flexural controls on late Neogene basin evolution in southern McMurdo Sound, Antarctica |
topic_facet |
Earth Sciences |
description |
The basins of southern McMurdo Sound have evolved under the influence of lithospheric flexure induced by the loads of the Erebus Volcanic Province. To characterise these basins, it is important to investigate the lithosphere's flexural properties, and estimate their influence on basin architecture and evolution. Seismic and gravity data are used to constrain 3D forward modelling of the progressive development of accommodation space within the flexural basins. Elastic plate flexure was calculated for a range of effective elastic thicknesses (Te) from 0.5 to 25 km using a spectral method. Models with low, but nonzero, Te values (2 km < Te < 5 km) produce the best fit to the gravity data, although uncertainty is high due to inaccuracies in the Digital Elevation Model. The slopes of flexural horizons revealed in seismic reflection lines are consistent with this, indicating a Te of 2 km to 5 km, although the depths to these horizons are not consistent, perhaps due to a northwards slope, or step, in the pre-flexural surface. These results indicate that the lithospheric strength of southern McMurdo Sound is significantly less than estimates of the regional average (Te ~ 20 km). This low strength may reflect the weakening effects of the Terror Rift, and perhaps also the Discovery Accommodation Zone, a region of major transverse faulting. A low Te model (Te = 3) for southern McMurdo Sound predicts the development of two discrete flexural depressions, each 2–2.5 km deep. The predicted stratigraphy of the northern basin reflects flexure due to Ross Island, predominantly erupted since ca. 1.8 Ma. The predicted stratigraphy of the southern basin reflects more gradual flexure from ca. 10 Ma to ca. 2 Ma, due to the more dispersed volcanoes of the Discovery subprovince. Collectively, these two basins have the potential to preserve a remarkable stratigraphic record of Antarctic climate change through the late Neogene. |
format |
Article in Journal/Newspaper |
author |
Aitken, Alan R.A. Wilson, Gary S. Jordan, Thomas Tinto, Kirsty Blakemore, Hamish |
author_facet |
Aitken, Alan R.A. Wilson, Gary S. Jordan, Thomas Tinto, Kirsty Blakemore, Hamish |
author_sort |
Aitken, Alan R.A. |
title |
Flexural controls on late Neogene basin evolution in southern McMurdo Sound, Antarctica |
title_short |
Flexural controls on late Neogene basin evolution in southern McMurdo Sound, Antarctica |
title_full |
Flexural controls on late Neogene basin evolution in southern McMurdo Sound, Antarctica |
title_fullStr |
Flexural controls on late Neogene basin evolution in southern McMurdo Sound, Antarctica |
title_full_unstemmed |
Flexural controls on late Neogene basin evolution in southern McMurdo Sound, Antarctica |
title_sort |
flexural controls on late neogene basin evolution in southern mcmurdo sound, antarctica |
publisher |
Elsevier |
publishDate |
2012 |
url |
http://nora.nerc.ac.uk/id/eprint/20845/ https://doi.org/10.1016/j.gloplacha.2011.08.003 |
geographic |
Antarctic McMurdo Sound Ross Island |
geographic_facet |
Antarctic McMurdo Sound Ross Island |
genre |
Antarc* Antarctic Antarctica McMurdo Sound Ross Island |
genre_facet |
Antarc* Antarctic Antarctica McMurdo Sound Ross Island |
op_relation |
Aitken, Alan R.A.; Wilson, Gary S.; Jordan, Thomas orcid:0000-0003-2780-1986 Tinto, Kirsty; Blakemore, Hamish. 2012 Flexural controls on late Neogene basin evolution in southern McMurdo Sound, Antarctica. Global and Planetary Change, 80-81. 99-112. https://doi.org/10.1016/j.gloplacha.2011.08.003 <https://doi.org/10.1016/j.gloplacha.2011.08.003> |
op_doi |
https://doi.org/10.1016/j.gloplacha.2011.08.003 |
container_title |
Global and Planetary Change |
container_volume |
80-81 |
container_start_page |
99 |
op_container_end_page |
112 |
_version_ |
1790594087838023680 |