Reconstructing Neogene Climate and Glacial History of Southern McMurdo Sound, Antarctica
Understanding the glacial changes that have occurred in southern McMurdo Sound throughout the Neogene makes an important contribution to reconstructing Antarctic ice volume changes during past periods of climatic warmth, and provides insight into future possible response of the ice sheet. Fossilifer...
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ftvictoriauwfig:oai:figshare.com:article/17065067 2023-05-15T13:35:14+02:00 Reconstructing Neogene Climate and Glacial History of Southern McMurdo Sound, Antarctica Galbraith, Elizabeth 2017-01-01T00:00:00Z https://doi.org/10.26686/wgtn.17065067.v1 https://figshare.com/articles/thesis/Reconstructing_Neogene_Climate_and_Glacial_History_of_Southern_McMurdo_Sound_Antarctica/17065067 unknown doi:10.26686/wgtn.17065067.v1 https://figshare.com/articles/thesis/Reconstructing_Neogene_Climate_and_Glacial_History_of_Southern_McMurdo_Sound_Antarctica/17065067 Author Retains Copyright Stratigraphy (incl. Biostratigraphy and Sequence Stratigraphy) Neogene Paleoclimate Antarctica McMurdo Sound School: School of Geography Environment and Earth Sciences Unit: Antarctic Research Centre 040311 Stratigraphy (incl. Biostratigraphy and Sequence Stratigraphy) 960306 Effects of Climate Change and Variability on Antarctic and Sub-Antarctic Environments (excl. Social Impacts) Degree Discipline: Geology Degree Level: Masters Degree Name: Master of Science Text Thesis 2017 ftvictoriauwfig https://doi.org/10.26686/wgtn.17065067.v1 2021-11-25T00:03:35Z Understanding the glacial changes that have occurred in southern McMurdo Sound throughout the Neogene makes an important contribution to reconstructing Antarctic ice volume changes during past periods of climatic warmth, and provides insight into future possible response of the ice sheet. Fossiliferous glacimarine deposits previously identified throughout McMurdo Sound have provided inferences on past changes in ice volume and the implications for global sea level. This study investigates new stratigraphic sections comprising fossiliferous glacimarine sediments from two locations on the flanks of Mount Discovery and one on Brown Peninsula at ~150m above present day sea-level. The aim of this thesis is to undertake a sedimentological, facies and glacimarine sequence stratigraphic analysis together with a quantitative assessment of the constituent micro and macrofossils in order to determine depositional processes, changes in environment and implications for glacial variability in the southern McMurdo Sound. Up to four distinct sedimentary cycles are evident in the Mt Discovery sections with each cycle consisting of: 1. A basal glacial surface of erosion (GSE) or its correlative conformity (CC) seaward of the grounding line, displaying an abrupt transition from a more distal facies to a more proximal facies. 2. A sharp-based massive diamictite displaying physical intermixing of subjacent lithologies, intra formational clasts, soft sediment deformation features, clast rotation features, and a lack of bioturbation, interpreted as subglacial, or in very close proximity to a marine grounding line. In some cases stratified diamictites overly correlative conformities displaying clast alignment, graded beds, and weak decimeter scale parallel bedding in the matrix, interpreted as grounding-line proximal sediment gravity flows or rain-out from ice melt. 3. In some cases, the diamictite passes gradationally-upwards or is sharply overlain by a conglomerate representing appearance of glacimarine fluvio-deltaic deposition or ... Thesis Antarc* Antarctic Antarctica Ice Sheet McMurdo Sound Open Access Victoria University of Wellington / Te Herenga Waka Antarctic Brown Peninsula ENVELOPE(165.417,165.417,-78.100,-78.100) McMurdo Sound Mount Discovery ENVELOPE(-59.716,-59.716,-62.483,-62.483) |
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Open Polar |
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Open Access Victoria University of Wellington / Te Herenga Waka |
op_collection_id |
ftvictoriauwfig |
language |
unknown |
topic |
Stratigraphy (incl. Biostratigraphy and Sequence Stratigraphy) Neogene Paleoclimate Antarctica McMurdo Sound School: School of Geography Environment and Earth Sciences Unit: Antarctic Research Centre 040311 Stratigraphy (incl. Biostratigraphy and Sequence Stratigraphy) 960306 Effects of Climate Change and Variability on Antarctic and Sub-Antarctic Environments (excl. Social Impacts) Degree Discipline: Geology Degree Level: Masters Degree Name: Master of Science |
spellingShingle |
Stratigraphy (incl. Biostratigraphy and Sequence Stratigraphy) Neogene Paleoclimate Antarctica McMurdo Sound School: School of Geography Environment and Earth Sciences Unit: Antarctic Research Centre 040311 Stratigraphy (incl. Biostratigraphy and Sequence Stratigraphy) 960306 Effects of Climate Change and Variability on Antarctic and Sub-Antarctic Environments (excl. Social Impacts) Degree Discipline: Geology Degree Level: Masters Degree Name: Master of Science Galbraith, Elizabeth Reconstructing Neogene Climate and Glacial History of Southern McMurdo Sound, Antarctica |
topic_facet |
Stratigraphy (incl. Biostratigraphy and Sequence Stratigraphy) Neogene Paleoclimate Antarctica McMurdo Sound School: School of Geography Environment and Earth Sciences Unit: Antarctic Research Centre 040311 Stratigraphy (incl. Biostratigraphy and Sequence Stratigraphy) 960306 Effects of Climate Change and Variability on Antarctic and Sub-Antarctic Environments (excl. Social Impacts) Degree Discipline: Geology Degree Level: Masters Degree Name: Master of Science |
description |
Understanding the glacial changes that have occurred in southern McMurdo Sound throughout the Neogene makes an important contribution to reconstructing Antarctic ice volume changes during past periods of climatic warmth, and provides insight into future possible response of the ice sheet. Fossiliferous glacimarine deposits previously identified throughout McMurdo Sound have provided inferences on past changes in ice volume and the implications for global sea level. This study investigates new stratigraphic sections comprising fossiliferous glacimarine sediments from two locations on the flanks of Mount Discovery and one on Brown Peninsula at ~150m above present day sea-level. The aim of this thesis is to undertake a sedimentological, facies and glacimarine sequence stratigraphic analysis together with a quantitative assessment of the constituent micro and macrofossils in order to determine depositional processes, changes in environment and implications for glacial variability in the southern McMurdo Sound. Up to four distinct sedimentary cycles are evident in the Mt Discovery sections with each cycle consisting of: 1. A basal glacial surface of erosion (GSE) or its correlative conformity (CC) seaward of the grounding line, displaying an abrupt transition from a more distal facies to a more proximal facies. 2. A sharp-based massive diamictite displaying physical intermixing of subjacent lithologies, intra formational clasts, soft sediment deformation features, clast rotation features, and a lack of bioturbation, interpreted as subglacial, or in very close proximity to a marine grounding line. In some cases stratified diamictites overly correlative conformities displaying clast alignment, graded beds, and weak decimeter scale parallel bedding in the matrix, interpreted as grounding-line proximal sediment gravity flows or rain-out from ice melt. 3. In some cases, the diamictite passes gradationally-upwards or is sharply overlain by a conglomerate representing appearance of glacimarine fluvio-deltaic deposition or ... |
format |
Thesis |
author |
Galbraith, Elizabeth |
author_facet |
Galbraith, Elizabeth |
author_sort |
Galbraith, Elizabeth |
title |
Reconstructing Neogene Climate and Glacial History of Southern McMurdo Sound, Antarctica |
title_short |
Reconstructing Neogene Climate and Glacial History of Southern McMurdo Sound, Antarctica |
title_full |
Reconstructing Neogene Climate and Glacial History of Southern McMurdo Sound, Antarctica |
title_fullStr |
Reconstructing Neogene Climate and Glacial History of Southern McMurdo Sound, Antarctica |
title_full_unstemmed |
Reconstructing Neogene Climate and Glacial History of Southern McMurdo Sound, Antarctica |
title_sort |
reconstructing neogene climate and glacial history of southern mcmurdo sound, antarctica |
publishDate |
2017 |
url |
https://doi.org/10.26686/wgtn.17065067.v1 https://figshare.com/articles/thesis/Reconstructing_Neogene_Climate_and_Glacial_History_of_Southern_McMurdo_Sound_Antarctica/17065067 |
long_lat |
ENVELOPE(165.417,165.417,-78.100,-78.100) ENVELOPE(-59.716,-59.716,-62.483,-62.483) |
geographic |
Antarctic Brown Peninsula McMurdo Sound Mount Discovery |
geographic_facet |
Antarctic Brown Peninsula McMurdo Sound Mount Discovery |
genre |
Antarc* Antarctic Antarctica Ice Sheet McMurdo Sound |
genre_facet |
Antarc* Antarctic Antarctica Ice Sheet McMurdo Sound |
op_relation |
doi:10.26686/wgtn.17065067.v1 https://figshare.com/articles/thesis/Reconstructing_Neogene_Climate_and_Glacial_History_of_Southern_McMurdo_Sound_Antarctica/17065067 |
op_rights |
Author Retains Copyright |
op_doi |
https://doi.org/10.26686/wgtn.17065067.v1 |
_version_ |
1766063288678875136 |