Calcium isotope (δ 44/40 Ca ) variations of Neogene planktonic foraminifera
Measurements of the calcium isotopic composition (δ44/40Ca) of planktonic foraminifera from the western equatorial Pacific and the Indian sector of the Southern Ocean show variations of about 0.6‰ over the past 24 Myr. The stacked δ44/40Ca record of Globigerinoides trilobus and Globigerina bulloides...
Published in: | Paleoceanography |
---|---|
Main Authors: | , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
AGU (American Geophysical Union)
2005
|
Subjects: | |
Online Access: | https://oceanrep.geomar.de/id/eprint/4910/ https://oceanrep.geomar.de/id/eprint/4910/1/palo1169.pdf https://doi.org/10.1029/2004PA001048 |
id |
ftoceanrep:oai:oceanrep.geomar.de:4910 |
---|---|
record_format |
openpolar |
spelling |
ftoceanrep:oai:oceanrep.geomar.de:4910 2023-05-15T18:00:35+02:00 Calcium isotope (δ 44/40 Ca ) variations of Neogene planktonic foraminifera Heuser, Alexander Eisenhauer, Anton Böhm, Florian Wallmann, Klaus Gussone, Nikolaus Pearson, P. N. Nägler, T. F. Dullo, Wolf-Christian 2005 text https://oceanrep.geomar.de/id/eprint/4910/ https://oceanrep.geomar.de/id/eprint/4910/1/palo1169.pdf https://doi.org/10.1029/2004PA001048 en eng AGU (American Geophysical Union) https://oceanrep.geomar.de/id/eprint/4910/1/palo1169.pdf Heuser, A., Eisenhauer, A. , Böhm, F., Wallmann, K. , Gussone, N., Pearson, P. N., Nägler, T. F. and Dullo, W. C. (2005) Calcium isotope (δ44/40Ca ) variations of Neogene planktonic foraminifera. Open Access Paleoceanography, 20 . PA2013. DOI 10.1029/2004PA001048 <https://doi.org/10.1029/2004PA001048>. doi:10.1029/2004PA001048 info:eu-repo/semantics/openAccess Article PeerReviewed 2005 ftoceanrep https://doi.org/10.1029/2004PA001048 2023-04-07T14:50:19Z Measurements of the calcium isotopic composition (δ44/40Ca) of planktonic foraminifera from the western equatorial Pacific and the Indian sector of the Southern Ocean show variations of about 0.6‰ over the past 24 Myr. The stacked δ44/40Ca record of Globigerinoides trilobus and Globigerina bulloides indicates a minimum in δ44/40Casw (seawater calcium) at 15 to 16 Ma and a subsequent general increase toward the present, interrupted by a second minimum at 3 to 5 Ma. Applying a coupled calcium/carbon cycle model, we find two scenarios that can explain a large portion of the observed δ44/40Casw variations. In both cases, variations in the Ca input flux to the ocean without proportional changes in the carbonate flux are invoked. The first scenario increases the riverine calcium input to the ocean without a proportional increase of the carbonate flux. The second scenario generates an additional calcium flux from the exchange of Ca by Mg during dolomitization. In both cases the calcium flux variations lead to drastic changes in the seawater Ca concentrations on million year timescales. Our δ44/40Casw record therefore indicates that the global calcium cycle may be much more dynamic than previously assumed. Article in Journal/Newspaper Planktonic foraminifera Southern Ocean OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Indian Pacific Southern Ocean Paleoceanography 20 2 n/a n/a |
institution |
Open Polar |
collection |
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
op_collection_id |
ftoceanrep |
language |
English |
description |
Measurements of the calcium isotopic composition (δ44/40Ca) of planktonic foraminifera from the western equatorial Pacific and the Indian sector of the Southern Ocean show variations of about 0.6‰ over the past 24 Myr. The stacked δ44/40Ca record of Globigerinoides trilobus and Globigerina bulloides indicates a minimum in δ44/40Casw (seawater calcium) at 15 to 16 Ma and a subsequent general increase toward the present, interrupted by a second minimum at 3 to 5 Ma. Applying a coupled calcium/carbon cycle model, we find two scenarios that can explain a large portion of the observed δ44/40Casw variations. In both cases, variations in the Ca input flux to the ocean without proportional changes in the carbonate flux are invoked. The first scenario increases the riverine calcium input to the ocean without a proportional increase of the carbonate flux. The second scenario generates an additional calcium flux from the exchange of Ca by Mg during dolomitization. In both cases the calcium flux variations lead to drastic changes in the seawater Ca concentrations on million year timescales. Our δ44/40Casw record therefore indicates that the global calcium cycle may be much more dynamic than previously assumed. |
format |
Article in Journal/Newspaper |
author |
Heuser, Alexander Eisenhauer, Anton Böhm, Florian Wallmann, Klaus Gussone, Nikolaus Pearson, P. N. Nägler, T. F. Dullo, Wolf-Christian |
spellingShingle |
Heuser, Alexander Eisenhauer, Anton Böhm, Florian Wallmann, Klaus Gussone, Nikolaus Pearson, P. N. Nägler, T. F. Dullo, Wolf-Christian Calcium isotope (δ 44/40 Ca ) variations of Neogene planktonic foraminifera |
author_facet |
Heuser, Alexander Eisenhauer, Anton Böhm, Florian Wallmann, Klaus Gussone, Nikolaus Pearson, P. N. Nägler, T. F. Dullo, Wolf-Christian |
author_sort |
Heuser, Alexander |
title |
Calcium isotope (δ 44/40 Ca ) variations of Neogene planktonic foraminifera |
title_short |
Calcium isotope (δ 44/40 Ca ) variations of Neogene planktonic foraminifera |
title_full |
Calcium isotope (δ 44/40 Ca ) variations of Neogene planktonic foraminifera |
title_fullStr |
Calcium isotope (δ 44/40 Ca ) variations of Neogene planktonic foraminifera |
title_full_unstemmed |
Calcium isotope (δ 44/40 Ca ) variations of Neogene planktonic foraminifera |
title_sort |
calcium isotope (δ 44/40 ca ) variations of neogene planktonic foraminifera |
publisher |
AGU (American Geophysical Union) |
publishDate |
2005 |
url |
https://oceanrep.geomar.de/id/eprint/4910/ https://oceanrep.geomar.de/id/eprint/4910/1/palo1169.pdf https://doi.org/10.1029/2004PA001048 |
geographic |
Indian Pacific Southern Ocean |
geographic_facet |
Indian Pacific Southern Ocean |
genre |
Planktonic foraminifera Southern Ocean |
genre_facet |
Planktonic foraminifera Southern Ocean |
op_relation |
https://oceanrep.geomar.de/id/eprint/4910/1/palo1169.pdf Heuser, A., Eisenhauer, A. , Böhm, F., Wallmann, K. , Gussone, N., Pearson, P. N., Nägler, T. F. and Dullo, W. C. (2005) Calcium isotope (δ44/40Ca ) variations of Neogene planktonic foraminifera. Open Access Paleoceanography, 20 . PA2013. DOI 10.1029/2004PA001048 <https://doi.org/10.1029/2004PA001048>. doi:10.1029/2004PA001048 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1029/2004PA001048 |
container_title |
Paleoceanography |
container_volume |
20 |
container_issue |
2 |
container_start_page |
n/a |
op_container_end_page |
n/a |
_version_ |
1766169728504561664 |