Holocene sediment transport and climate variability of offshore Adélie Land, East Antarctica
Grain size analysis of the terrigenous fraction of a laminated diatom ooze dating back to 11.4 kyr recovered offshore Adélie Land, East Antarctic margin was used to examine variations in sediment transport, depositional environments and Holocene climate variability at the location. Interpretations w...
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ftvuwellington:oai:researcharchive.vuw.ac.nz:10063/6171 2023-08-15T12:38:20+02:00 Holocene sediment transport and climate variability of offshore Adélie Land, East Antarctica Albot, Anna Borisovna Carter, Lionel McKay, Rob 2017 http://researcharchive.vuw.ac.nz/handle/10063/6171 en_NZ eng Victoria University of Wellington http://researcharchive.vuw.ac.nz/handle/10063/6171 Holocene Sediment Antarctica Text Master's 2017 ftvuwellington 2023-07-25T17:26:49Z Grain size analysis of the terrigenous fraction of a laminated diatom ooze dating back to 11.4 kyr recovered offshore Adélie Land, East Antarctic margin was used to examine variations in sediment transport, depositional environments and Holocene climate variability at the location. Interpretations were assisted by additional proxies of primary productivity (δ¹³CFA, BSi%), glacial meltwater input (δDFA) and subsurface temperature (TEXL₈₆). Three lithologic intervals with distinct grain size distributions were identified. At ~11.4 ka the diatom ooze has a clear glacimarine influence which gradually decreases until ~8.2 ka. During this time interval, coincident with the early Holocene warm period, sediment is inferred to have been delivered by glacial meltwater plumes and ice-bergs in a calving bay environment. It is suggested that the glaciers in Adélie Land had retreated to their present day grounding lines by 8.2 ka, and from then on sediment was delivered to the site primarily via the Antarctic Coastal and Slope Front Currents, largely through a suspended sediment load and erosion of the surrounding banks. Enhanced biogenic mass accumulation rates and primary production at 8.2 ka suggest onset of warmer climatic conditions, coincident with the mid-Holocene Climatic Optimum. At ~4.5 ka, grain size distributions show a rapid increase in mud content coincident with a transient pulse of glacial meltwater and a sudden decrease in biogenic and terrigenous mass accumulation rates. The increased mud content is inferred to have been deposited under a reduced flow regime of the Antarctic Coastal and Slope Front Currents during the Neoglacial period that followed the final stages of deglaciation in the Ross Sea. It is hypothesised here that cessation of glacial retreat in the Ross Sea and the development of the modern day Ross Sea polynya resulted in enhanced Antarctic Surface Water production which led to increased sea ice growth in the Adélie Land region. The presence of sea ice led to reduced primary production and a ... Master Thesis Antarc* Antarctic Antarctica East Antarctica Ross Sea Sea ice Victoria University of Wellington: ResearchArchive Antarctic East Antarctica Ross Sea The Antarctic |
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Victoria University of Wellington: ResearchArchive |
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English |
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Holocene Sediment Antarctica |
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Holocene Sediment Antarctica Albot, Anna Borisovna Holocene sediment transport and climate variability of offshore Adélie Land, East Antarctica |
topic_facet |
Holocene Sediment Antarctica |
description |
Grain size analysis of the terrigenous fraction of a laminated diatom ooze dating back to 11.4 kyr recovered offshore Adélie Land, East Antarctic margin was used to examine variations in sediment transport, depositional environments and Holocene climate variability at the location. Interpretations were assisted by additional proxies of primary productivity (δ¹³CFA, BSi%), glacial meltwater input (δDFA) and subsurface temperature (TEXL₈₆). Three lithologic intervals with distinct grain size distributions were identified. At ~11.4 ka the diatom ooze has a clear glacimarine influence which gradually decreases until ~8.2 ka. During this time interval, coincident with the early Holocene warm period, sediment is inferred to have been delivered by glacial meltwater plumes and ice-bergs in a calving bay environment. It is suggested that the glaciers in Adélie Land had retreated to their present day grounding lines by 8.2 ka, and from then on sediment was delivered to the site primarily via the Antarctic Coastal and Slope Front Currents, largely through a suspended sediment load and erosion of the surrounding banks. Enhanced biogenic mass accumulation rates and primary production at 8.2 ka suggest onset of warmer climatic conditions, coincident with the mid-Holocene Climatic Optimum. At ~4.5 ka, grain size distributions show a rapid increase in mud content coincident with a transient pulse of glacial meltwater and a sudden decrease in biogenic and terrigenous mass accumulation rates. The increased mud content is inferred to have been deposited under a reduced flow regime of the Antarctic Coastal and Slope Front Currents during the Neoglacial period that followed the final stages of deglaciation in the Ross Sea. It is hypothesised here that cessation of glacial retreat in the Ross Sea and the development of the modern day Ross Sea polynya resulted in enhanced Antarctic Surface Water production which led to increased sea ice growth in the Adélie Land region. The presence of sea ice led to reduced primary production and a ... |
author2 |
Carter, Lionel McKay, Rob |
format |
Master Thesis |
author |
Albot, Anna Borisovna |
author_facet |
Albot, Anna Borisovna |
author_sort |
Albot, Anna Borisovna |
title |
Holocene sediment transport and climate variability of offshore Adélie Land, East Antarctica |
title_short |
Holocene sediment transport and climate variability of offshore Adélie Land, East Antarctica |
title_full |
Holocene sediment transport and climate variability of offshore Adélie Land, East Antarctica |
title_fullStr |
Holocene sediment transport and climate variability of offshore Adélie Land, East Antarctica |
title_full_unstemmed |
Holocene sediment transport and climate variability of offshore Adélie Land, East Antarctica |
title_sort |
holocene sediment transport and climate variability of offshore adélie land, east antarctica |
publisher |
Victoria University of Wellington |
publishDate |
2017 |
url |
http://researcharchive.vuw.ac.nz/handle/10063/6171 |
geographic |
Antarctic East Antarctica Ross Sea The Antarctic |
geographic_facet |
Antarctic East Antarctica Ross Sea The Antarctic |
genre |
Antarc* Antarctic Antarctica East Antarctica Ross Sea Sea ice |
genre_facet |
Antarc* Antarctic Antarctica East Antarctica Ross Sea Sea ice |
op_relation |
http://researcharchive.vuw.ac.nz/handle/10063/6171 |
_version_ |
1774299657560653824 |