Large 14C age offsets between the fine fraction and coexisting planktonic foraminifera in shallow Caribbean sediments
International audience Absolute chronologies in paleoceanographic records are often constructed using the 14C dating of coarse fraction foraminifera (>150 μm). However, due to processes such as changes in sediment sources or abundances, sedimentation rates, bioturbation, reworking, the adsorption...
Published in: | Quaternary Geochronology |
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Main Authors: | , , |
Other Authors: | , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
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HAL CCSD
2017
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Online Access: | https://hal.science/hal-01485928 https://doi.org/10.1016/j.quageo.2016.12.002 |
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ftinraparis:oai:HAL:hal-01485928v1 |
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Open Polar |
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Institut National de la Recherche Agronomique: ProdINRA |
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ftinraparis |
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English |
topic |
[SDU]Sciences of the Universe [physics] |
spellingShingle |
[SDU]Sciences of the Universe [physics] Sepulcre, Sophie Durand, N. Bard, E. Large 14C age offsets between the fine fraction and coexisting planktonic foraminifera in shallow Caribbean sediments |
topic_facet |
[SDU]Sciences of the Universe [physics] |
description |
International audience Absolute chronologies in paleoceanographic records are often constructed using the 14C dating of coarse fraction foraminifera (>150 μm). However, due to processes such as changes in sediment sources or abundances, sedimentation rates, bioturbation, reworking, the adsorption of modern carbon, etc., several studies conducted in different environmental settings have shown time-lags between records obtained from various granulometric fractions. In this study, we examined temporal phasing between the coarse foraminifera and fine fractions by studying changes in the abundances of δ18O, the 14C ages of the planktonic foraminifera Globigerinoides ruber (G. ruber, 250–350 μm), and the sediment fine fraction (<63 μm) over the last 45 ka in a core obtained from the northern Caribbean Sea. All of the records were found to be in phase during part of the Holocene (at least for the last ≈6 ka). As determined from δ18O records and 14C ages, the fine fraction was younger than G. ruber during the Last Deglaciation (of 1.89 ka). The coupling between bioturbation and changes in the fine fraction, and G. ruber abundances, as tested using a numerical model of the bioturbation record within a mixed-layer depth of 8 cm, was sufficient to explain the results. 14C age discrepancies increased from 5.64 to 8.5 ka during Marine Isotopic Stages (MIS) 2 and 3, respectively. These chronological discrepancies could not be explained by only one process and seemed to result from the interplay between mechanisms: size-differentiated bioturbation (for 1.5 to 2.5 ka), the adsorption of modern atmospheric CO2 (for 3.04 to 5.92 ka), and variations in sedimentological processes that influenced the fine carbonate fraction. However, even if variations in the mineralogical composition of the fine carbonate fraction were identified using scanning-electron microscopy observations, X-ray diffraction measurements, and geochemical analyses (the mol % MgCO3 of magnesian calcite and the Sr/Ca ratio of the bulk fine fraction), they ... |
author2 |
Collège de France - Chaire Evolution du climat et de l'océan Centre Européen de Recherche et d'Enseignement des Géosciences de l'Environnement (CEREGE) Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) Géosciences Paris Sud (GEOPS) Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS) Laboratoire de mesure du carbone 14 (LMC14 - UMS 2572) Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Radioprotection et de Sûreté Nucléaire (IRSN)-Ministère de la Culture et de la Communication (MCC)-Centre National de la Recherche Scientifique (CNRS) Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE) Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)) Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA) |
format |
Article in Journal/Newspaper |
author |
Sepulcre, Sophie Durand, N. Bard, E. |
author_facet |
Sepulcre, Sophie Durand, N. Bard, E. |
author_sort |
Sepulcre, Sophie |
title |
Large 14C age offsets between the fine fraction and coexisting planktonic foraminifera in shallow Caribbean sediments |
title_short |
Large 14C age offsets between the fine fraction and coexisting planktonic foraminifera in shallow Caribbean sediments |
title_full |
Large 14C age offsets between the fine fraction and coexisting planktonic foraminifera in shallow Caribbean sediments |
title_fullStr |
Large 14C age offsets between the fine fraction and coexisting planktonic foraminifera in shallow Caribbean sediments |
title_full_unstemmed |
Large 14C age offsets between the fine fraction and coexisting planktonic foraminifera in shallow Caribbean sediments |
title_sort |
large 14c age offsets between the fine fraction and coexisting planktonic foraminifera in shallow caribbean sediments |
publisher |
HAL CCSD |
publishDate |
2017 |
url |
https://hal.science/hal-01485928 https://doi.org/10.1016/j.quageo.2016.12.002 |
genre |
Planktonic foraminifera |
genre_facet |
Planktonic foraminifera |
op_source |
ISSN: 1871-1014 Quaternary Geochronology https://hal.science/hal-01485928 Quaternary Geochronology, 2017, 38:, pp.61-74 (IF 3,142). ⟨10.1016/j.quageo.2016.12.002⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1016/j.quageo.2016.12.002 hal-01485928 https://hal.science/hal-01485928 doi:10.1016/j.quageo.2016.12.002 |
op_doi |
https://doi.org/10.1016/j.quageo.2016.12.002 |
container_title |
Quaternary Geochronology |
container_volume |
38 |
container_start_page |
61 |
op_container_end_page |
74 |
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1802649257557098496 |
spelling |
ftinraparis:oai:HAL:hal-01485928v1 2024-06-23T07:56:16+00:00 Large 14C age offsets between the fine fraction and coexisting planktonic foraminifera in shallow Caribbean sediments Sepulcre, Sophie Durand, N. Bard, E. Collège de France - Chaire Evolution du climat et de l'océan Centre Européen de Recherche et d'Enseignement des Géosciences de l'Environnement (CEREGE) Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) Géosciences Paris Sud (GEOPS) Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS) Laboratoire de mesure du carbone 14 (LMC14 - UMS 2572) Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Radioprotection et de Sûreté Nucléaire (IRSN)-Ministère de la Culture et de la Communication (MCC)-Centre National de la Recherche Scientifique (CNRS) Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE) Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)) Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA) 2017 https://hal.science/hal-01485928 https://doi.org/10.1016/j.quageo.2016.12.002 en eng HAL CCSD Elsevier info:eu-repo/semantics/altIdentifier/doi/10.1016/j.quageo.2016.12.002 hal-01485928 https://hal.science/hal-01485928 doi:10.1016/j.quageo.2016.12.002 ISSN: 1871-1014 Quaternary Geochronology https://hal.science/hal-01485928 Quaternary Geochronology, 2017, 38:, pp.61-74 (IF 3,142). ⟨10.1016/j.quageo.2016.12.002⟩ [SDU]Sciences of the Universe [physics] info:eu-repo/semantics/article Journal articles 2017 ftinraparis https://doi.org/10.1016/j.quageo.2016.12.002 2024-06-11T15:06:06Z International audience Absolute chronologies in paleoceanographic records are often constructed using the 14C dating of coarse fraction foraminifera (>150 μm). However, due to processes such as changes in sediment sources or abundances, sedimentation rates, bioturbation, reworking, the adsorption of modern carbon, etc., several studies conducted in different environmental settings have shown time-lags between records obtained from various granulometric fractions. In this study, we examined temporal phasing between the coarse foraminifera and fine fractions by studying changes in the abundances of δ18O, the 14C ages of the planktonic foraminifera Globigerinoides ruber (G. ruber, 250–350 μm), and the sediment fine fraction (<63 μm) over the last 45 ka in a core obtained from the northern Caribbean Sea. All of the records were found to be in phase during part of the Holocene (at least for the last ≈6 ka). As determined from δ18O records and 14C ages, the fine fraction was younger than G. ruber during the Last Deglaciation (of 1.89 ka). The coupling between bioturbation and changes in the fine fraction, and G. ruber abundances, as tested using a numerical model of the bioturbation record within a mixed-layer depth of 8 cm, was sufficient to explain the results. 14C age discrepancies increased from 5.64 to 8.5 ka during Marine Isotopic Stages (MIS) 2 and 3, respectively. These chronological discrepancies could not be explained by only one process and seemed to result from the interplay between mechanisms: size-differentiated bioturbation (for 1.5 to 2.5 ka), the adsorption of modern atmospheric CO2 (for 3.04 to 5.92 ka), and variations in sedimentological processes that influenced the fine carbonate fraction. However, even if variations in the mineralogical composition of the fine carbonate fraction were identified using scanning-electron microscopy observations, X-ray diffraction measurements, and geochemical analyses (the mol % MgCO3 of magnesian calcite and the Sr/Ca ratio of the bulk fine fraction), they ... Article in Journal/Newspaper Planktonic foraminifera Institut National de la Recherche Agronomique: ProdINRA Quaternary Geochronology 38 61 74 |