Cenozoic reconstruction of Cape Darnley Bottom Water paleo-distribution imprinted in the drift formation history off MacRobertson Land Shelf, East Antarctica
Formation of Antarctic Bottom Water (AABW) plays an essential role within Meridional Overturning Circulation and is widely accepted to be the engine of global Thermohaline Circulation (THC), which is sensitive to climate changes. Studying paleo conditions and changes of AABW distribution during warm...
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ftawi:oai:epic.awi.de:54383 2024-09-15T17:42:30+00:00 Cenozoic reconstruction of Cape Darnley Bottom Water paleo-distribution imprinted in the drift formation history off MacRobertson Land Shelf, East Antarctica Nielsen, Ricarda Uenzelmann-Neben, Gabriele 2021-04-19 https://epic.awi.de/id/eprint/54383/ https://hdl.handle.net/10013/epic.d0f20dac-ce0f-4cc9-8e2f-ad88c28b272f unknown EGU21-8061 Nielsen, R. orcid:0000-0002-1232-2950 and Uenzelmann-Neben, G. orcid:0000-0002-0115-5923 , Alfred-Wegener Institut, Helmholtz Zentrum für Polar und Meeresforschung (2021) Cenozoic reconstruction of Cape Darnley Bottom Water paleo-distribution imprinted in the drift formation history off MacRobertson Land Shelf, East Antarctica , EGU General Assembly, online, 19 April 2021 - 30 April 2021 . doi:10.5194/egusphere-egu21-8061 <https://doi.org/10.5194/egusphere-egu21-8061> , hdl:10013/epic.d0f20dac-ce0f-4cc9-8e2f-ad88c28b272f EPIC3EGU General Assembly, online, 2021-04-19-2021-04-30EGU21-8061 Conference notRev 2021 ftawi https://doi.org/10.5194/egusphere-egu21-8061 2024-06-24T04:27:29Z Formation of Antarctic Bottom Water (AABW) plays an essential role within Meridional Overturning Circulation and is widely accepted to be the engine of global Thermohaline Circulation (THC), which is sensitive to climate changes. Studying paleo conditions and changes of AABW distribution during warm and cold periods is fundamental to gain knowledge about its interaction and response to climate changes, which helps to understand recent and future changes of THC due to global warming. West of Prydz Bay, along MacRobertson Land Shelf area, a recent production of dense shelf water in the Cape Darnley Polynya and outflow as so-called Cape Darnley Bottom Water (CDBW) along the Wild Canyon has been recognized. CDBW contributes around 6-13% to the total circumpolar AABW. In order to understand the paleo conditions of AABW it is necessary to investigate the paleo-evolution of CDBW. To do this, we have studied the formation history of a 200 km long sediment drift (Darnley Drift herein) at the western flank of the Wild Canyon. We utilized more than 13.000 km of multi-channel seismic reflection data and lithological Data of ODP Site 1165. We characterized Darnley Drift to be a mixed turbiditic-contourite drift formed by an interplay of downslope and along-slope processes. During the Oligocene, turbiditic outflow dominated along the later formed Wild Canyon. An onset of CDBW can be inferred during the early Miocene, forming an asymmetric channel-levee system along the Wild Canyon. After the mid-Miocene Climatic Optimum a major climate change occurred, resulting in a strong intensification of bottom currents and major growth of the drift with simultaneous areas of non-deposition and erosion. This was followed by a sharp reduction of sedimentation rates. Since the late Miocene the growth of Darnley Drift is further dominated by contourite bottom currents. Conference Object Antarc* Antarctic Antarctica East Antarctica MacRobertson Land Prydz Bay Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
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Open Polar |
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Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
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ftawi |
language |
unknown |
description |
Formation of Antarctic Bottom Water (AABW) plays an essential role within Meridional Overturning Circulation and is widely accepted to be the engine of global Thermohaline Circulation (THC), which is sensitive to climate changes. Studying paleo conditions and changes of AABW distribution during warm and cold periods is fundamental to gain knowledge about its interaction and response to climate changes, which helps to understand recent and future changes of THC due to global warming. West of Prydz Bay, along MacRobertson Land Shelf area, a recent production of dense shelf water in the Cape Darnley Polynya and outflow as so-called Cape Darnley Bottom Water (CDBW) along the Wild Canyon has been recognized. CDBW contributes around 6-13% to the total circumpolar AABW. In order to understand the paleo conditions of AABW it is necessary to investigate the paleo-evolution of CDBW. To do this, we have studied the formation history of a 200 km long sediment drift (Darnley Drift herein) at the western flank of the Wild Canyon. We utilized more than 13.000 km of multi-channel seismic reflection data and lithological Data of ODP Site 1165. We characterized Darnley Drift to be a mixed turbiditic-contourite drift formed by an interplay of downslope and along-slope processes. During the Oligocene, turbiditic outflow dominated along the later formed Wild Canyon. An onset of CDBW can be inferred during the early Miocene, forming an asymmetric channel-levee system along the Wild Canyon. After the mid-Miocene Climatic Optimum a major climate change occurred, resulting in a strong intensification of bottom currents and major growth of the drift with simultaneous areas of non-deposition and erosion. This was followed by a sharp reduction of sedimentation rates. Since the late Miocene the growth of Darnley Drift is further dominated by contourite bottom currents. |
format |
Conference Object |
author |
Nielsen, Ricarda Uenzelmann-Neben, Gabriele |
spellingShingle |
Nielsen, Ricarda Uenzelmann-Neben, Gabriele Cenozoic reconstruction of Cape Darnley Bottom Water paleo-distribution imprinted in the drift formation history off MacRobertson Land Shelf, East Antarctica |
author_facet |
Nielsen, Ricarda Uenzelmann-Neben, Gabriele |
author_sort |
Nielsen, Ricarda |
title |
Cenozoic reconstruction of Cape Darnley Bottom Water paleo-distribution imprinted in the drift formation history off MacRobertson Land Shelf, East Antarctica |
title_short |
Cenozoic reconstruction of Cape Darnley Bottom Water paleo-distribution imprinted in the drift formation history off MacRobertson Land Shelf, East Antarctica |
title_full |
Cenozoic reconstruction of Cape Darnley Bottom Water paleo-distribution imprinted in the drift formation history off MacRobertson Land Shelf, East Antarctica |
title_fullStr |
Cenozoic reconstruction of Cape Darnley Bottom Water paleo-distribution imprinted in the drift formation history off MacRobertson Land Shelf, East Antarctica |
title_full_unstemmed |
Cenozoic reconstruction of Cape Darnley Bottom Water paleo-distribution imprinted in the drift formation history off MacRobertson Land Shelf, East Antarctica |
title_sort |
cenozoic reconstruction of cape darnley bottom water paleo-distribution imprinted in the drift formation history off macrobertson land shelf, east antarctica |
publisher |
EGU21-8061 |
publishDate |
2021 |
url |
https://epic.awi.de/id/eprint/54383/ https://hdl.handle.net/10013/epic.d0f20dac-ce0f-4cc9-8e2f-ad88c28b272f |
genre |
Antarc* Antarctic Antarctica East Antarctica MacRobertson Land Prydz Bay |
genre_facet |
Antarc* Antarctic Antarctica East Antarctica MacRobertson Land Prydz Bay |
op_source |
EPIC3EGU General Assembly, online, 2021-04-19-2021-04-30EGU21-8061 |
op_relation |
Nielsen, R. orcid:0000-0002-1232-2950 and Uenzelmann-Neben, G. orcid:0000-0002-0115-5923 , Alfred-Wegener Institut, Helmholtz Zentrum für Polar und Meeresforschung (2021) Cenozoic reconstruction of Cape Darnley Bottom Water paleo-distribution imprinted in the drift formation history off MacRobertson Land Shelf, East Antarctica , EGU General Assembly, online, 19 April 2021 - 30 April 2021 . doi:10.5194/egusphere-egu21-8061 <https://doi.org/10.5194/egusphere-egu21-8061> , hdl:10013/epic.d0f20dac-ce0f-4cc9-8e2f-ad88c28b272f |
op_doi |
https://doi.org/10.5194/egusphere-egu21-8061 |
_version_ |
1810489085283794944 |