Magnesium/Calcium ratios in benthic foraminifera from surface sediments
We used modern epibenthic foraminifer tests of Cibicidoides mundulus and Planulina wuellerstorfi from South Atlantic core top sediments in order to establish Mg/Ca-temperature relationships for the temperature range from 0 to 15°C. We obtained the following calibrations: Mg/Ca (mmol/mol) = 0.830*exp...
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ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.759564 2023-05-15T17:25:29+02:00 Magnesium/Calcium ratios in benthic foraminifera from surface sediments Raitzsch, Markus Kuhnert, Henning Groeneveld, Jeroen Bickert, Torsten MEDIAN LATITUDE: -28.834968 * MEDIAN LONGITUDE: -19.330520 * SOUTH-BOUND LATITUDE: -48.013333 * WEST-BOUND LONGITUDE: -58.518200 * NORTH-BOUND LATITUDE: -1.665000 * EAST-BOUND LONGITUDE: 17.755000 * DATE/TIME START: 1988-03-12T00:00:00 * DATE/TIME END: 2003-02-27T00:00:00 * MINIMUM DEPTH, sediment/rock: 0.005 m * MAXIMUM DEPTH, sediment/rock: 0.005 m 2008-04-16 text/tab-separated-values, 246 data points https://doi.pangaea.de/10.1594/PANGAEA.759564 https://doi.org/10.1594/PANGAEA.759564 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.759564 https://doi.org/10.1594/PANGAEA.759564 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess CC-BY Supplement to: Raitzsch, Markus; Kuhnert, Henning; Groeneveld, Jeroen; Bickert, Torsten (2008): Benthic foraminifer Mg/Ca anomalies in South Atlantic core top sediments and their implications for paleothermometry. Geochemistry, Geophysics, Geosystems, 9(5), Q05010, https://doi.org/10.1029/2007GC001788 B_LANDER Bottom lander Brazil Basin Cape Basin Cibicidoides mundulus Magnesium/Calcium ratio standard deviation Continental slope off Brazil Depth bottom/max sediment/rock top/min Equatorial Atlantic Event label GeoB1041-1 GeoB1105-3 GeoB1113-7 GeoB1118-2 GeoB1203-2 GeoB1216-2 GeoB1217-1 GeoB1218-1 GeoB1707-2 GeoB1710-2 GeoB1711-5 GeoB1712-2 GeoB1713-6 GeoB1715-3 GeoB1719-2 GeoB1720-4 GeoB1721-5 GeoB1726-2 GeoB1728-3 GeoB1729-2 GeoB2102-1 GeoB2105-3 GeoB2106-1 GeoB2107-5 GeoB2715-1 GeoB2718-2 GeoB2727-1 GeoB3602-2 GeoB3603-1 GeoB3803-1 GeoB3804-2 GeoB3807-1 Dataset 2008 ftpangaea https://doi.org/10.1594/PANGAEA.759564 https://doi.org/10.1029/2007GC001788 2023-01-20T08:52:08Z We used modern epibenthic foraminifer tests of Cibicidoides mundulus and Planulina wuellerstorfi from South Atlantic core top sediments in order to establish Mg/Ca-temperature relationships for the temperature range from 0 to 15°C. We obtained the following calibrations: Mg/Ca (mmol/mol) = 0.830*exp(0.145*BWT (°C)) for P. wuellerstorfi, and Mg/Ca (mmol/mol) = 0.627*exp(0.143*BWT (°C)) for C. mundulus. However, a number of tests, especially those bathed in North Atlantic Deep Water, revealed higher Mg/Ca ratios than predicted from the calibration. Our data suggest that d[CO3 2-] of bottom water exerts a significant control on dMg/Ca (temperature-corrected) of C. mundulus (dMg/Ca = 0.017*d[CO3 2-] -0.14), while dMg/Ca of P. wuellerstorfi is more likely to be governed by TCO2 (dMg/Ca = -0.007*TCO2 + 15). Since both d[CO3 2-] and TCO2 are closely linked to [CO3 2-], it is inferred that carbonate ion acts as secondary control, after temperature, on benthic shell Mg/Ca below -4°C. A drop in [CO3 2-] by 25 ?mol/kg at 4 km water depth, as suggested for the Last Glacial Maximum, would decrease Mg/Ca by up to 0.4 mmol/mol, which leads to an underestimation of bottom water temperature by -3.5°C. Therefore our results indicate that the Mg/Ca thermometer should be used cautiously for benthic foraminifers where changes in the carbonate chemistry are present in the paleoceanographic record. Dataset North Atlantic Deep Water North Atlantic PANGAEA - Data Publisher for Earth & Environmental Science ENVELOPE(-58.518200,17.755000,-1.665000,-48.013333) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
B_LANDER Bottom lander Brazil Basin Cape Basin Cibicidoides mundulus Magnesium/Calcium ratio standard deviation Continental slope off Brazil Depth bottom/max sediment/rock top/min Equatorial Atlantic Event label GeoB1041-1 GeoB1105-3 GeoB1113-7 GeoB1118-2 GeoB1203-2 GeoB1216-2 GeoB1217-1 GeoB1218-1 GeoB1707-2 GeoB1710-2 GeoB1711-5 GeoB1712-2 GeoB1713-6 GeoB1715-3 GeoB1719-2 GeoB1720-4 GeoB1721-5 GeoB1726-2 GeoB1728-3 GeoB1729-2 GeoB2102-1 GeoB2105-3 GeoB2106-1 GeoB2107-5 GeoB2715-1 GeoB2718-2 GeoB2727-1 GeoB3602-2 GeoB3603-1 GeoB3803-1 GeoB3804-2 GeoB3807-1 |
spellingShingle |
B_LANDER Bottom lander Brazil Basin Cape Basin Cibicidoides mundulus Magnesium/Calcium ratio standard deviation Continental slope off Brazil Depth bottom/max sediment/rock top/min Equatorial Atlantic Event label GeoB1041-1 GeoB1105-3 GeoB1113-7 GeoB1118-2 GeoB1203-2 GeoB1216-2 GeoB1217-1 GeoB1218-1 GeoB1707-2 GeoB1710-2 GeoB1711-5 GeoB1712-2 GeoB1713-6 GeoB1715-3 GeoB1719-2 GeoB1720-4 GeoB1721-5 GeoB1726-2 GeoB1728-3 GeoB1729-2 GeoB2102-1 GeoB2105-3 GeoB2106-1 GeoB2107-5 GeoB2715-1 GeoB2718-2 GeoB2727-1 GeoB3602-2 GeoB3603-1 GeoB3803-1 GeoB3804-2 GeoB3807-1 Raitzsch, Markus Kuhnert, Henning Groeneveld, Jeroen Bickert, Torsten Magnesium/Calcium ratios in benthic foraminifera from surface sediments |
topic_facet |
B_LANDER Bottom lander Brazil Basin Cape Basin Cibicidoides mundulus Magnesium/Calcium ratio standard deviation Continental slope off Brazil Depth bottom/max sediment/rock top/min Equatorial Atlantic Event label GeoB1041-1 GeoB1105-3 GeoB1113-7 GeoB1118-2 GeoB1203-2 GeoB1216-2 GeoB1217-1 GeoB1218-1 GeoB1707-2 GeoB1710-2 GeoB1711-5 GeoB1712-2 GeoB1713-6 GeoB1715-3 GeoB1719-2 GeoB1720-4 GeoB1721-5 GeoB1726-2 GeoB1728-3 GeoB1729-2 GeoB2102-1 GeoB2105-3 GeoB2106-1 GeoB2107-5 GeoB2715-1 GeoB2718-2 GeoB2727-1 GeoB3602-2 GeoB3603-1 GeoB3803-1 GeoB3804-2 GeoB3807-1 |
description |
We used modern epibenthic foraminifer tests of Cibicidoides mundulus and Planulina wuellerstorfi from South Atlantic core top sediments in order to establish Mg/Ca-temperature relationships for the temperature range from 0 to 15°C. We obtained the following calibrations: Mg/Ca (mmol/mol) = 0.830*exp(0.145*BWT (°C)) for P. wuellerstorfi, and Mg/Ca (mmol/mol) = 0.627*exp(0.143*BWT (°C)) for C. mundulus. However, a number of tests, especially those bathed in North Atlantic Deep Water, revealed higher Mg/Ca ratios than predicted from the calibration. Our data suggest that d[CO3 2-] of bottom water exerts a significant control on dMg/Ca (temperature-corrected) of C. mundulus (dMg/Ca = 0.017*d[CO3 2-] -0.14), while dMg/Ca of P. wuellerstorfi is more likely to be governed by TCO2 (dMg/Ca = -0.007*TCO2 + 15). Since both d[CO3 2-] and TCO2 are closely linked to [CO3 2-], it is inferred that carbonate ion acts as secondary control, after temperature, on benthic shell Mg/Ca below -4°C. A drop in [CO3 2-] by 25 ?mol/kg at 4 km water depth, as suggested for the Last Glacial Maximum, would decrease Mg/Ca by up to 0.4 mmol/mol, which leads to an underestimation of bottom water temperature by -3.5°C. Therefore our results indicate that the Mg/Ca thermometer should be used cautiously for benthic foraminifers where changes in the carbonate chemistry are present in the paleoceanographic record. |
format |
Dataset |
author |
Raitzsch, Markus Kuhnert, Henning Groeneveld, Jeroen Bickert, Torsten |
author_facet |
Raitzsch, Markus Kuhnert, Henning Groeneveld, Jeroen Bickert, Torsten |
author_sort |
Raitzsch, Markus |
title |
Magnesium/Calcium ratios in benthic foraminifera from surface sediments |
title_short |
Magnesium/Calcium ratios in benthic foraminifera from surface sediments |
title_full |
Magnesium/Calcium ratios in benthic foraminifera from surface sediments |
title_fullStr |
Magnesium/Calcium ratios in benthic foraminifera from surface sediments |
title_full_unstemmed |
Magnesium/Calcium ratios in benthic foraminifera from surface sediments |
title_sort |
magnesium/calcium ratios in benthic foraminifera from surface sediments |
publisher |
PANGAEA |
publishDate |
2008 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.759564 https://doi.org/10.1594/PANGAEA.759564 |
op_coverage |
MEDIAN LATITUDE: -28.834968 * MEDIAN LONGITUDE: -19.330520 * SOUTH-BOUND LATITUDE: -48.013333 * WEST-BOUND LONGITUDE: -58.518200 * NORTH-BOUND LATITUDE: -1.665000 * EAST-BOUND LONGITUDE: 17.755000 * DATE/TIME START: 1988-03-12T00:00:00 * DATE/TIME END: 2003-02-27T00:00:00 * MINIMUM DEPTH, sediment/rock: 0.005 m * MAXIMUM DEPTH, sediment/rock: 0.005 m |
long_lat |
ENVELOPE(-58.518200,17.755000,-1.665000,-48.013333) |
genre |
North Atlantic Deep Water North Atlantic |
genre_facet |
North Atlantic Deep Water North Atlantic |
op_source |
Supplement to: Raitzsch, Markus; Kuhnert, Henning; Groeneveld, Jeroen; Bickert, Torsten (2008): Benthic foraminifer Mg/Ca anomalies in South Atlantic core top sediments and their implications for paleothermometry. Geochemistry, Geophysics, Geosystems, 9(5), Q05010, https://doi.org/10.1029/2007GC001788 |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.759564 https://doi.org/10.1594/PANGAEA.759564 |
op_rights |
CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1594/PANGAEA.759564 https://doi.org/10.1029/2007GC001788 |
_version_ |
1766116928095518720 |