Benthic foraminifer stable isotope record from Site 849 (0 - 5 Ma) : local and global climate changes
Benthic foraminifer and δ¹³C data from Site 849, on the west flank of the East Pacific Rise (0°11'N, 110°3l'W; 3851 m), give relatively continuous records of deep Pacific Ocean stable isotope variations between 0 and 5 Ma. The mean sample spacing is 4 k.y. Most analyses are from Cibicides...
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ftoregonstate:ir.library.oregonstate.edu:3197xs10q 2024-04-14T08:02:20+00:00 Benthic foraminifer stable isotope record from Site 849 (0 - 5 Ma) : local and global climate changes Mix, Alan C. Pisias, Nicklas G. Rugh, W. Wilson, J. Morey, A. Hagelberg, T. K. https://ir.library.oregonstate.edu/concern/articles/3197xs10q English [eng] eng unknown Proceedings of the Ocean Drilling Program, Scientific Results https://ir.library.oregonstate.edu/concern/articles/3197xs10q Copyright Not Evaluated Article ftoregonstate 2024-03-21T15:41:27Z Benthic foraminifer and δ¹³C data from Site 849, on the west flank of the East Pacific Rise (0°11'N, 110°3l'W; 3851 m), give relatively continuous records of deep Pacific Ocean stable isotope variations between 0 and 5 Ma. The mean sample spacing is 4 k.y. Most analyses are from Cibicides wuellerstorfi> but isotopic offsets relative to Uvigerina peregrina appear roughly constant. Because of its location west of the East Pacific Rise, Site 849 yields a suitable record of mean Pacific Ocean δ¹³C, which approximates a global oceanic signal. The ~lOO-k.y.-period climate cycle, which is prevalent in δ¹⁸O does not dominate the long-term δ¹³C record. For δ¹³C, variations in the -400- and 41-k.y. periods are more important. Phase lags of δ¹³C relative to ice volume in the 41- and 23-k.y. bands are consistent with δ¹³C as a measure of organic biomass. A model-calculated exponential response time of 1-2 k.y. is appropriate for carbon stored in soils and shallow sediments responding to glacial-interglacial climate change. Oceanic δ¹³C leads ice volume slightly in the 100-k.y. band, and this suggests another process such as changes in continental weathering to modulate mean river δ¹³C at long periods. The δ¹³C record from Site 849 diverges from that of Site 677 in the Panama Basin mostly because of decay of ¹³C-depleted organic carbon in the relatively isolated Panama Basin. North Atlantic to Pacific δ¹³C differences calculated using published data from Sites 607 and 849 reveal variations in Pliocene deep water within the range of those of the late Quaternary. Maximum δ¹³C contrast between these sites, which presumably reflects maximum influx of high-δ¹³C northern source water into the deep North Atlantic Ocean, occurred between 1.3 and 2.1 Ma, well after the initiation of Northern Hemisphere glaciation. Export of high-δ¹³C North Atlantic Deep Water from the Atlantic to the circumpolar Antarctic, as recorded by published δ'3C data from Subantarctic Site 704, appears unrelated to the North Atlantic-Pacific δ¹³C contrast. ... Article in Journal/Newspaper Antarc* Antarctic North Atlantic Deep Water North Atlantic ScholarsArchive@OSU (Oregon State University) Antarctic Pacific |
institution |
Open Polar |
collection |
ScholarsArchive@OSU (Oregon State University) |
op_collection_id |
ftoregonstate |
language |
English unknown |
description |
Benthic foraminifer and δ¹³C data from Site 849, on the west flank of the East Pacific Rise (0°11'N, 110°3l'W; 3851 m), give relatively continuous records of deep Pacific Ocean stable isotope variations between 0 and 5 Ma. The mean sample spacing is 4 k.y. Most analyses are from Cibicides wuellerstorfi> but isotopic offsets relative to Uvigerina peregrina appear roughly constant. Because of its location west of the East Pacific Rise, Site 849 yields a suitable record of mean Pacific Ocean δ¹³C, which approximates a global oceanic signal. The ~lOO-k.y.-period climate cycle, which is prevalent in δ¹⁸O does not dominate the long-term δ¹³C record. For δ¹³C, variations in the -400- and 41-k.y. periods are more important. Phase lags of δ¹³C relative to ice volume in the 41- and 23-k.y. bands are consistent with δ¹³C as a measure of organic biomass. A model-calculated exponential response time of 1-2 k.y. is appropriate for carbon stored in soils and shallow sediments responding to glacial-interglacial climate change. Oceanic δ¹³C leads ice volume slightly in the 100-k.y. band, and this suggests another process such as changes in continental weathering to modulate mean river δ¹³C at long periods. The δ¹³C record from Site 849 diverges from that of Site 677 in the Panama Basin mostly because of decay of ¹³C-depleted organic carbon in the relatively isolated Panama Basin. North Atlantic to Pacific δ¹³C differences calculated using published data from Sites 607 and 849 reveal variations in Pliocene deep water within the range of those of the late Quaternary. Maximum δ¹³C contrast between these sites, which presumably reflects maximum influx of high-δ¹³C northern source water into the deep North Atlantic Ocean, occurred between 1.3 and 2.1 Ma, well after the initiation of Northern Hemisphere glaciation. Export of high-δ¹³C North Atlantic Deep Water from the Atlantic to the circumpolar Antarctic, as recorded by published δ'3C data from Subantarctic Site 704, appears unrelated to the North Atlantic-Pacific δ¹³C contrast. ... |
format |
Article in Journal/Newspaper |
author |
Mix, Alan C. Pisias, Nicklas G. Rugh, W. Wilson, J. Morey, A. Hagelberg, T. K. |
spellingShingle |
Mix, Alan C. Pisias, Nicklas G. Rugh, W. Wilson, J. Morey, A. Hagelberg, T. K. Benthic foraminifer stable isotope record from Site 849 (0 - 5 Ma) : local and global climate changes |
author_facet |
Mix, Alan C. Pisias, Nicklas G. Rugh, W. Wilson, J. Morey, A. Hagelberg, T. K. |
author_sort |
Mix, Alan C. |
title |
Benthic foraminifer stable isotope record from Site 849 (0 - 5 Ma) : local and global climate changes |
title_short |
Benthic foraminifer stable isotope record from Site 849 (0 - 5 Ma) : local and global climate changes |
title_full |
Benthic foraminifer stable isotope record from Site 849 (0 - 5 Ma) : local and global climate changes |
title_fullStr |
Benthic foraminifer stable isotope record from Site 849 (0 - 5 Ma) : local and global climate changes |
title_full_unstemmed |
Benthic foraminifer stable isotope record from Site 849 (0 - 5 Ma) : local and global climate changes |
title_sort |
benthic foraminifer stable isotope record from site 849 (0 - 5 ma) : local and global climate changes |
publisher |
Proceedings of the Ocean Drilling Program, Scientific Results |
url |
https://ir.library.oregonstate.edu/concern/articles/3197xs10q |
geographic |
Antarctic Pacific |
geographic_facet |
Antarctic Pacific |
genre |
Antarc* Antarctic North Atlantic Deep Water North Atlantic |
genre_facet |
Antarc* Antarctic North Atlantic Deep Water North Atlantic |
op_relation |
https://ir.library.oregonstate.edu/concern/articles/3197xs10q |
op_rights |
Copyright Not Evaluated |
_version_ |
1796314241351811072 |