Determination of the Mg/Mn ratio in foraminiferal coatings: An approach to correct Mg/Ca temperatures for Mn-rich contaminant phases
The occurrence of manganese-rich coatings on foraminifera can have a significant effect on their bulk Mg/Ca ratios thereby biasing seawater temperature reconstructions. The removal of this Mn phase requires a reductive cleaning step, but this has been suggested to preferentially dissolve Mg-rich bio...
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ftunivbern:oai:boris.unibe.ch:90474 2023-08-20T04:00:37+02:00 Determination of the Mg/Mn ratio in foraminiferal coatings: An approach to correct Mg/Ca temperatures for Mn-rich contaminant phases Hasenfratz, Adam P. Martinez-García, Alfredo Jaccard, Samuel Vance, Derek Wälle, Markus Greaves, Mervyn Haug, Gerald 2017-01-01 application/pdf https://boris.unibe.ch/90474/1/Hasenfratz%20et%20al.,%2017.pdf https://boris.unibe.ch/90474/ eng eng Elsevier https://boris.unibe.ch/90474/ info:eu-repo/semantics/restrictedAccess Hasenfratz, Adam P.; Martinez-García, Alfredo; Jaccard, Samuel; Vance, Derek; Wälle, Markus; Greaves, Mervyn; Haug, Gerald (2017). Determination of the Mg/Mn ratio in foraminiferal coatings: An approach to correct Mg/Ca temperatures for Mn-rich contaminant phases. Earth and planetary science letters, 457, pp. 335-347. Elsevier 10.1016/j.epsl.2016.10.004 <http://dx.doi.org/10.1016/j.epsl.2016.10.004> 550 Earth sciences & geology info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion PeerReviewed 2017 ftunivbern https://doi.org/10.1016/j.epsl.2016.10.004 2023-07-31T21:30:15Z The occurrence of manganese-rich coatings on foraminifera can have a significant effect on their bulk Mg/Ca ratios thereby biasing seawater temperature reconstructions. The removal of this Mn phase requires a reductive cleaning step, but this has been suggested to preferentially dissolve Mg-rich biogenic carbonate, potentially introducing an analytical bias in paleotemperature estimates. In this study, the geochemical composition of foraminifera tests from Mn-rich sediments from the Antarctic Southern Ocean (ODP Site 1094) was investigated using solution-based and laser ablation ICP-MS in order to determine the amount of Mg incorporated into the coatings. The analysis of planktonic and benthic foraminifera revealed a nearly constant Mg/Mn ratio in the Mn coating of ∼0.2mol/mol. Consequently, the coating Mg/Mn ratio can be used to correct for the Mg incorporated into the Mn phase by using the down core Mn/Ca values of samples that have not been reductively cleaned. The consistency of the coating Mg/Mn ratio obtained in this study, as well as that found in samples from the Panama Basin, suggests that spatial variation of Mg/Mn in foraminiferal Mn overgrowths may be smaller than expected from Mn nodules and Mn–Ca carbonates. However, a site-specific assessment of the Mg/Mn ratio in foraminiferal coatings is recommended to improve the accuracy of the correction. Article in Journal/Newspaper Antarc* Antarctic Southern Ocean BORIS (Bern Open Repository and Information System, University of Bern) Antarctic Southern Ocean The Antarctic Earth and Planetary Science Letters 457 335 347 |
institution |
Open Polar |
collection |
BORIS (Bern Open Repository and Information System, University of Bern) |
op_collection_id |
ftunivbern |
language |
English |
topic |
550 Earth sciences & geology |
spellingShingle |
550 Earth sciences & geology Hasenfratz, Adam P. Martinez-García, Alfredo Jaccard, Samuel Vance, Derek Wälle, Markus Greaves, Mervyn Haug, Gerald Determination of the Mg/Mn ratio in foraminiferal coatings: An approach to correct Mg/Ca temperatures for Mn-rich contaminant phases |
topic_facet |
550 Earth sciences & geology |
description |
The occurrence of manganese-rich coatings on foraminifera can have a significant effect on their bulk Mg/Ca ratios thereby biasing seawater temperature reconstructions. The removal of this Mn phase requires a reductive cleaning step, but this has been suggested to preferentially dissolve Mg-rich biogenic carbonate, potentially introducing an analytical bias in paleotemperature estimates. In this study, the geochemical composition of foraminifera tests from Mn-rich sediments from the Antarctic Southern Ocean (ODP Site 1094) was investigated using solution-based and laser ablation ICP-MS in order to determine the amount of Mg incorporated into the coatings. The analysis of planktonic and benthic foraminifera revealed a nearly constant Mg/Mn ratio in the Mn coating of ∼0.2mol/mol. Consequently, the coating Mg/Mn ratio can be used to correct for the Mg incorporated into the Mn phase by using the down core Mn/Ca values of samples that have not been reductively cleaned. The consistency of the coating Mg/Mn ratio obtained in this study, as well as that found in samples from the Panama Basin, suggests that spatial variation of Mg/Mn in foraminiferal Mn overgrowths may be smaller than expected from Mn nodules and Mn–Ca carbonates. However, a site-specific assessment of the Mg/Mn ratio in foraminiferal coatings is recommended to improve the accuracy of the correction. |
format |
Article in Journal/Newspaper |
author |
Hasenfratz, Adam P. Martinez-García, Alfredo Jaccard, Samuel Vance, Derek Wälle, Markus Greaves, Mervyn Haug, Gerald |
author_facet |
Hasenfratz, Adam P. Martinez-García, Alfredo Jaccard, Samuel Vance, Derek Wälle, Markus Greaves, Mervyn Haug, Gerald |
author_sort |
Hasenfratz, Adam P. |
title |
Determination of the Mg/Mn ratio in foraminiferal coatings: An approach to correct Mg/Ca temperatures for Mn-rich contaminant phases |
title_short |
Determination of the Mg/Mn ratio in foraminiferal coatings: An approach to correct Mg/Ca temperatures for Mn-rich contaminant phases |
title_full |
Determination of the Mg/Mn ratio in foraminiferal coatings: An approach to correct Mg/Ca temperatures for Mn-rich contaminant phases |
title_fullStr |
Determination of the Mg/Mn ratio in foraminiferal coatings: An approach to correct Mg/Ca temperatures for Mn-rich contaminant phases |
title_full_unstemmed |
Determination of the Mg/Mn ratio in foraminiferal coatings: An approach to correct Mg/Ca temperatures for Mn-rich contaminant phases |
title_sort |
determination of the mg/mn ratio in foraminiferal coatings: an approach to correct mg/ca temperatures for mn-rich contaminant phases |
publisher |
Elsevier |
publishDate |
2017 |
url |
https://boris.unibe.ch/90474/1/Hasenfratz%20et%20al.,%2017.pdf https://boris.unibe.ch/90474/ |
geographic |
Antarctic Southern Ocean The Antarctic |
geographic_facet |
Antarctic Southern Ocean The Antarctic |
genre |
Antarc* Antarctic Southern Ocean |
genre_facet |
Antarc* Antarctic Southern Ocean |
op_source |
Hasenfratz, Adam P.; Martinez-García, Alfredo; Jaccard, Samuel; Vance, Derek; Wälle, Markus; Greaves, Mervyn; Haug, Gerald (2017). Determination of the Mg/Mn ratio in foraminiferal coatings: An approach to correct Mg/Ca temperatures for Mn-rich contaminant phases. Earth and planetary science letters, 457, pp. 335-347. Elsevier 10.1016/j.epsl.2016.10.004 <http://dx.doi.org/10.1016/j.epsl.2016.10.004> |
op_relation |
https://boris.unibe.ch/90474/ |
op_rights |
info:eu-repo/semantics/restrictedAccess |
op_doi |
https://doi.org/10.1016/j.epsl.2016.10.004 |
container_title |
Earth and Planetary Science Letters |
container_volume |
457 |
container_start_page |
335 |
op_container_end_page |
347 |
_version_ |
1774719293075750912 |