Reconstructing deglacial North and South Atlantic deep water sourcing using foraminiferal Nd isotopes
During the last few decades, neodymium isotopes have been increasingly used as a paleoceanographic and paleoclimate proxy on million-year through millennial time-scales. The widespread use of the Nd isotope proxy depends on whether the Nd isotopic composition of past seawater can be reliably extract...
Published in: | Earth and Planetary Science Letters |
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Online Access: | http://hdl.handle.net/1885/71887 https://doi.org/10.1016/j.epsl.2012.09.036 https://openresearch-repository.anu.edu.au/bitstream/1885/71887/5/f5625xPUB2934_2012.pdf.jpg https://openresearch-repository.anu.edu.au/bitstream/1885/71887/7/01_Piotrowski_Reconstructing_deglacial_North_2012.pdf.jpg |
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ftanucanberra:oai:openresearch-repository.anu.edu.au:1885/71887 2024-01-14T10:08:49+01:00 Reconstructing deglacial North and South Atlantic deep water sourcing using foraminiferal Nd isotopes Piotrowski, Alexander Galy, A Nicholl, J A L Roberts, N Wilson, D J Clegg, J A Yu, Jimin http://hdl.handle.net/1885/71887 https://doi.org/10.1016/j.epsl.2012.09.036 https://openresearch-repository.anu.edu.au/bitstream/1885/71887/5/f5625xPUB2934_2012.pdf.jpg https://openresearch-repository.anu.edu.au/bitstream/1885/71887/7/01_Piotrowski_Reconstructing_deglacial_North_2012.pdf.jpg unknown Elsevier 0012-821X http://hdl.handle.net/1885/71887 doi:10.1016/j.epsl.2012.09.036 https://openresearch-repository.anu.edu.au/bitstream/1885/71887/5/f5625xPUB2934_2012.pdf.jpg https://openresearch-repository.anu.edu.au/bitstream/1885/71887/7/01_Piotrowski_Reconstructing_deglacial_North_2012.pdf.jpg Earth and Planetary Science Letters Keywords: Atlantic Ocean Authigenic Bottom water Chemical gradients Deep Water Deglacial Deglaciations Holocene values Isotopic signatures Nd isotopes Nd isotopic compositions North Atlantic North Atlantic Deep Water Northeastern Atlantic Ocean circul Geochemistry Neodymium isotopes Ocean circulation Paleoceanography Paleoclimate Journal article ftanucanberra https://doi.org/10.1016/j.epsl.2012.09.036 2023-12-15T09:35:12Z During the last few decades, neodymium isotopes have been increasingly used as a paleoceanographic and paleoclimate proxy on million-year through millennial time-scales. The widespread use of the Nd isotope proxy depends on whether the Nd isotopic composition of past seawater can be reliably extracted from authigenic sediment phases. Here we show evidence that planktonic foraminifera with authigenic coatings preserve a deep water Nd isotopic signature and thus can be used to reconstruct past deep water Nd isotopes. Applying this method downcore on South Atlantic Deep Cape Basin core TNO57-21 (41.1°S, 7.9°E, 4981. m), the Nd isotopic composition of the planktonic foraminiferal Fe-Mn oxide coatings is identical with and confirms that of the reductively leached bulk sediment fraction (Piotrowski et al., 2004, 2005, 2008) as reflecting changes in bottom water sourcing. In the case of northeastern North Atlantic core BOFS 8K (52.5°N 22.1°W, 4045. m), the planktonic foraminiferal Fe-Mn oxide coatings have different Nd isotopes from reductive sediment leaches. Clearly acid-reductive leaching must be tested in more detail. We observe that the Nd isotopic composition of the deep northeastern Atlantic core shifted during the deglaciation, from glacial values similar to the South Atlantic Cape Basin towards Holocene values similar to the Bermuda Rise (Roberts et al., 2010). Taken as a whole, the Nd isotope record from foraminiferal authigenic coatings suggests large-scale changes in the proportion of northern and southern deep water sources occurred throughout the Atlantic Ocean, with substantial chemical gradients at times, during the last deglaciation. Article in Journal/Newspaper North Atlantic Deep Water North Atlantic Planktonic foraminifera Australian National University: ANU Digital Collections Earth and Planetary Science Letters 357-358 289 297 |
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Open Polar |
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Australian National University: ANU Digital Collections |
op_collection_id |
ftanucanberra |
language |
unknown |
topic |
Keywords: Atlantic Ocean Authigenic Bottom water Chemical gradients Deep Water Deglacial Deglaciations Holocene values Isotopic signatures Nd isotopes Nd isotopic compositions North Atlantic North Atlantic Deep Water Northeastern Atlantic Ocean circul Geochemistry Neodymium isotopes Ocean circulation Paleoceanography Paleoclimate |
spellingShingle |
Keywords: Atlantic Ocean Authigenic Bottom water Chemical gradients Deep Water Deglacial Deglaciations Holocene values Isotopic signatures Nd isotopes Nd isotopic compositions North Atlantic North Atlantic Deep Water Northeastern Atlantic Ocean circul Geochemistry Neodymium isotopes Ocean circulation Paleoceanography Paleoclimate Piotrowski, Alexander Galy, A Nicholl, J A L Roberts, N Wilson, D J Clegg, J A Yu, Jimin Reconstructing deglacial North and South Atlantic deep water sourcing using foraminiferal Nd isotopes |
topic_facet |
Keywords: Atlantic Ocean Authigenic Bottom water Chemical gradients Deep Water Deglacial Deglaciations Holocene values Isotopic signatures Nd isotopes Nd isotopic compositions North Atlantic North Atlantic Deep Water Northeastern Atlantic Ocean circul Geochemistry Neodymium isotopes Ocean circulation Paleoceanography Paleoclimate |
description |
During the last few decades, neodymium isotopes have been increasingly used as a paleoceanographic and paleoclimate proxy on million-year through millennial time-scales. The widespread use of the Nd isotope proxy depends on whether the Nd isotopic composition of past seawater can be reliably extracted from authigenic sediment phases. Here we show evidence that planktonic foraminifera with authigenic coatings preserve a deep water Nd isotopic signature and thus can be used to reconstruct past deep water Nd isotopes. Applying this method downcore on South Atlantic Deep Cape Basin core TNO57-21 (41.1°S, 7.9°E, 4981. m), the Nd isotopic composition of the planktonic foraminiferal Fe-Mn oxide coatings is identical with and confirms that of the reductively leached bulk sediment fraction (Piotrowski et al., 2004, 2005, 2008) as reflecting changes in bottom water sourcing. In the case of northeastern North Atlantic core BOFS 8K (52.5°N 22.1°W, 4045. m), the planktonic foraminiferal Fe-Mn oxide coatings have different Nd isotopes from reductive sediment leaches. Clearly acid-reductive leaching must be tested in more detail. We observe that the Nd isotopic composition of the deep northeastern Atlantic core shifted during the deglaciation, from glacial values similar to the South Atlantic Cape Basin towards Holocene values similar to the Bermuda Rise (Roberts et al., 2010). Taken as a whole, the Nd isotope record from foraminiferal authigenic coatings suggests large-scale changes in the proportion of northern and southern deep water sources occurred throughout the Atlantic Ocean, with substantial chemical gradients at times, during the last deglaciation. |
format |
Article in Journal/Newspaper |
author |
Piotrowski, Alexander Galy, A Nicholl, J A L Roberts, N Wilson, D J Clegg, J A Yu, Jimin |
author_facet |
Piotrowski, Alexander Galy, A Nicholl, J A L Roberts, N Wilson, D J Clegg, J A Yu, Jimin |
author_sort |
Piotrowski, Alexander |
title |
Reconstructing deglacial North and South Atlantic deep water sourcing using foraminiferal Nd isotopes |
title_short |
Reconstructing deglacial North and South Atlantic deep water sourcing using foraminiferal Nd isotopes |
title_full |
Reconstructing deglacial North and South Atlantic deep water sourcing using foraminiferal Nd isotopes |
title_fullStr |
Reconstructing deglacial North and South Atlantic deep water sourcing using foraminiferal Nd isotopes |
title_full_unstemmed |
Reconstructing deglacial North and South Atlantic deep water sourcing using foraminiferal Nd isotopes |
title_sort |
reconstructing deglacial north and south atlantic deep water sourcing using foraminiferal nd isotopes |
publisher |
Elsevier |
url |
http://hdl.handle.net/1885/71887 https://doi.org/10.1016/j.epsl.2012.09.036 https://openresearch-repository.anu.edu.au/bitstream/1885/71887/5/f5625xPUB2934_2012.pdf.jpg https://openresearch-repository.anu.edu.au/bitstream/1885/71887/7/01_Piotrowski_Reconstructing_deglacial_North_2012.pdf.jpg |
genre |
North Atlantic Deep Water North Atlantic Planktonic foraminifera |
genre_facet |
North Atlantic Deep Water North Atlantic Planktonic foraminifera |
op_source |
Earth and Planetary Science Letters |
op_relation |
0012-821X http://hdl.handle.net/1885/71887 doi:10.1016/j.epsl.2012.09.036 https://openresearch-repository.anu.edu.au/bitstream/1885/71887/5/f5625xPUB2934_2012.pdf.jpg https://openresearch-repository.anu.edu.au/bitstream/1885/71887/7/01_Piotrowski_Reconstructing_deglacial_North_2012.pdf.jpg |
op_doi |
https://doi.org/10.1016/j.epsl.2012.09.036 |
container_title |
Earth and Planetary Science Letters |
container_volume |
357-358 |
container_start_page |
289 |
op_container_end_page |
297 |
_version_ |
1788063224680153088 |