Carbonate dissolution revealed by silt grain-size distribution: comparison of Holocene and Last Glacial Maximum sediments from the pelagic South Atlantic
The current issue of global warming and the role of the ocean in global exchange of CO2 increases the interest in solid budgets of marine carbonate production and dissolution. The present study utilizes grain-size composition of pelagic sediments in order to trace spatial and temporal variability of...
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Online Access: | http://nora.nerc.ac.uk/id/eprint/149694/ http://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-3091.2006.00841.x https://doi.org/10.1111/j.1365-3091.2006.00841.x |
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ftnerc:oai:nora.nerc.ac.uk:149694 2023-05-15T13:48:07+02:00 Carbonate dissolution revealed by silt grain-size distribution: comparison of Holocene and Last Glacial Maximum sediments from the pelagic South Atlantic Frenz, M. Henrich, R. 2007-04 http://nora.nerc.ac.uk/id/eprint/149694/ http://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-3091.2006.00841.x https://doi.org/10.1111/j.1365-3091.2006.00841.x unknown Frenz, M.; Henrich, R. 2007 Carbonate dissolution revealed by silt grain-size distribution: comparison of Holocene and Last Glacial Maximum sediments from the pelagic South Atlantic. Sedimentology, 54 (2). 391-404. https://doi.org/10.1111/j.1365-3091.2006.00841.x <https://doi.org/10.1111/j.1365-3091.2006.00841.x> Publication - Article PeerReviewed 2007 ftnerc https://doi.org/10.1111/j.1365-3091.2006.00841.x 2023-02-04T19:34:52Z The current issue of global warming and the role of the ocean in global exchange of CO2 increases the interest in solid budgets of marine carbonate production and dissolution. The present study utilizes grain-size composition of pelagic sediments in order to trace spatial and temporal variability of carbonate sedimentation in the South Atlantic for the Holocene and Last Glacial Maximum (LGM, 19–23 cal kyr BP). A decrease in grain size (e.g. sand content, mean grain size of coarse carbonate silt) indicates increased carbonate dissolution as a result of increased fragmentation of calcareous microfossils. The spatial grain-size pattern suggests a threshold water depth below which a gradual grain-size decrease becomes increasingly rapid. This water depth is considered as the sedimentary lysocline. For the Holocene time slice, a constant, gradual decrease of foraminifer carbonate of about 5–10% per 1000 m water depth above the lysocline gives evidence for supra-lysoclinal dissolution. The water depth of the lysocline for the Holocene is tied to the interface of North Atlantic Deep Water and Antarctic Bottom Water (AABW) (ca 4100 m). Submarine ridges which restrict intrusion of AABW into the Angola Basin cause an asymmetry in carbonate preservation across the Mid-Atlantic Ridge. The lysocline was reconstructed at ca 3100 m for the LGM. These data suggest that the ca 1000 m rise of the lysocline eradicated the Holocene east–west asymmetry. Article in Journal/Newspaper Antarc* Antarctic North Atlantic Deep Water North Atlantic Natural Environment Research Council: NERC Open Research Archive Antarctic Mid-Atlantic Ridge Sedimentology 54 2 391 404 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
unknown |
description |
The current issue of global warming and the role of the ocean in global exchange of CO2 increases the interest in solid budgets of marine carbonate production and dissolution. The present study utilizes grain-size composition of pelagic sediments in order to trace spatial and temporal variability of carbonate sedimentation in the South Atlantic for the Holocene and Last Glacial Maximum (LGM, 19–23 cal kyr BP). A decrease in grain size (e.g. sand content, mean grain size of coarse carbonate silt) indicates increased carbonate dissolution as a result of increased fragmentation of calcareous microfossils. The spatial grain-size pattern suggests a threshold water depth below which a gradual grain-size decrease becomes increasingly rapid. This water depth is considered as the sedimentary lysocline. For the Holocene time slice, a constant, gradual decrease of foraminifer carbonate of about 5–10% per 1000 m water depth above the lysocline gives evidence for supra-lysoclinal dissolution. The water depth of the lysocline for the Holocene is tied to the interface of North Atlantic Deep Water and Antarctic Bottom Water (AABW) (ca 4100 m). Submarine ridges which restrict intrusion of AABW into the Angola Basin cause an asymmetry in carbonate preservation across the Mid-Atlantic Ridge. The lysocline was reconstructed at ca 3100 m for the LGM. These data suggest that the ca 1000 m rise of the lysocline eradicated the Holocene east–west asymmetry. |
format |
Article in Journal/Newspaper |
author |
Frenz, M. Henrich, R. |
spellingShingle |
Frenz, M. Henrich, R. Carbonate dissolution revealed by silt grain-size distribution: comparison of Holocene and Last Glacial Maximum sediments from the pelagic South Atlantic |
author_facet |
Frenz, M. Henrich, R. |
author_sort |
Frenz, M. |
title |
Carbonate dissolution revealed by silt grain-size distribution: comparison of Holocene and Last Glacial Maximum sediments from the pelagic South Atlantic |
title_short |
Carbonate dissolution revealed by silt grain-size distribution: comparison of Holocene and Last Glacial Maximum sediments from the pelagic South Atlantic |
title_full |
Carbonate dissolution revealed by silt grain-size distribution: comparison of Holocene and Last Glacial Maximum sediments from the pelagic South Atlantic |
title_fullStr |
Carbonate dissolution revealed by silt grain-size distribution: comparison of Holocene and Last Glacial Maximum sediments from the pelagic South Atlantic |
title_full_unstemmed |
Carbonate dissolution revealed by silt grain-size distribution: comparison of Holocene and Last Glacial Maximum sediments from the pelagic South Atlantic |
title_sort |
carbonate dissolution revealed by silt grain-size distribution: comparison of holocene and last glacial maximum sediments from the pelagic south atlantic |
publishDate |
2007 |
url |
http://nora.nerc.ac.uk/id/eprint/149694/ http://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-3091.2006.00841.x https://doi.org/10.1111/j.1365-3091.2006.00841.x |
geographic |
Antarctic Mid-Atlantic Ridge |
geographic_facet |
Antarctic Mid-Atlantic Ridge |
genre |
Antarc* Antarctic North Atlantic Deep Water North Atlantic |
genre_facet |
Antarc* Antarctic North Atlantic Deep Water North Atlantic |
op_relation |
Frenz, M.; Henrich, R. 2007 Carbonate dissolution revealed by silt grain-size distribution: comparison of Holocene and Last Glacial Maximum sediments from the pelagic South Atlantic. Sedimentology, 54 (2). 391-404. https://doi.org/10.1111/j.1365-3091.2006.00841.x <https://doi.org/10.1111/j.1365-3091.2006.00841.x> |
op_doi |
https://doi.org/10.1111/j.1365-3091.2006.00841.x |
container_title |
Sedimentology |
container_volume |
54 |
container_issue |
2 |
container_start_page |
391 |
op_container_end_page |
404 |
_version_ |
1766248613357289472 |