Thorium and radiocarbon measurements on sediment cores from the Northseast Atlantic
Radiocarbon and 230Thexcess data from six NE Atlantic box cores are considered. The cores form a transect from the Porcupine Abyssal Plain over the East Thulean Rise to the southern end of Feni Drift. The chronology for the cores is established from bulk sediment carbonate radiocarbon data and revea...
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1993
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ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.734066 2024-09-15T18:25:30+00:00 Thorium and radiocarbon measurements on sediment cores from the Northseast Atlantic Thomson, John Colley, S Anderson, Robert F Cook, G T MacKenzie, Angus Harkness, Douglas D MEDIAN LATITUDE: 50.949168 * MEDIAN LONGITUDE: -21.399984 * SOUTH-BOUND LATITUDE: 47.773700 * WEST-BOUND LONGITUDE: -22.592000 * NORTH-BOUND LATITUDE: 53.703500 * EAST-BOUND LONGITUDE: -19.710700 * DATE/TIME START: 1989-07-22T00:00:00 * DATE/TIME END: 1989-07-31T00:00:00 1993 application/zip, 7 datasets https://doi.pangaea.de/10.1594/PANGAEA.734066 https://doi.org/10.1594/PANGAEA.734066 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.734066 https://doi.org/10.1594/PANGAEA.734066 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess Supplement to: Thomson, John; Colley, S; Anderson, Robert F; Cook, G T; MacKenzie, Angus; Harkness, Douglas D (1993): Holocene sediment fluxes in the northeast Atlantic from 230Th excess and radiocarbon measurements. Paleoceanography, 8(5), 631-650, https://doi.org/10.1029/93PA01366 BC Biogeochemical Ocean Flux Study BOFS BOFS11880#5 BOFS11881#4 BOFS11882#3 BOFS11884#2 BOFS11886#4 BOFS11889#4 BOFS3C BOFS4C BOFS5C BOFS7C BOFS8C BOFS9C Box corer D184 Discovery (1962) JGOFS Joint Global Ocean Flux Study Northeast Atlantic dataset publication series 1993 ftpangaea https://doi.org/10.1594/PANGAEA.73406610.1029/93PA01366 2024-07-24T02:31:20Z Radiocarbon and 230Thexcess data from six NE Atlantic box cores are considered. The cores form a transect from the Porcupine Abyssal Plain over the East Thulean Rise to the southern end of Feni Drift. The chronology for the cores is established from bulk sediment carbonate radiocarbon data and reveals that sections exhibiting constant accumulation rates can be identified in all the cores, with rates of 3.0-3.5 cm/kyr on the plain through the Holocene and late Holocene rates of 4.3-6.6 cm/kyr elsewhere. Five out of the six cores show accumulations of more 230Thexcess than is produced in the overlying water column, with the greatest inventories (up to 225% of production) in the cores from the rise and drift. A size fraction comparison between two cores from the plain and rise reveals that the higher overall accumulation rates and 230Thexcess inventories in the off-plain cores are due to an increased fine (<5 µm) component fraction, whereas the flux of coarser material is similar to that received on the plain. This suggests that the higher fluxes of materials observed are physically (rather than biogeochemically) driven and also that drift formation has been continuously active in the late Holocene. Sections of all the cores where regular accumulation is defined by the radiocarbon data are modeled first by a linear radiocarbon age/depth model and second by a constant rain (230Thexcess)0 model prorated for the observed core inventories. These modeling approaches yield historical mass accumulation rate estimates which are generally in reasonable agreement (±30%), but the differences observed appear to be well organized in time rather than random. Other/Unknown Material Northeast Atlantic PANGAEA - Data Publisher for Earth & Environmental Science ENVELOPE(-22.592000,-19.710700,53.703500,47.773700) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
BC Biogeochemical Ocean Flux Study BOFS BOFS11880#5 BOFS11881#4 BOFS11882#3 BOFS11884#2 BOFS11886#4 BOFS11889#4 BOFS3C BOFS4C BOFS5C BOFS7C BOFS8C BOFS9C Box corer D184 Discovery (1962) JGOFS Joint Global Ocean Flux Study Northeast Atlantic |
spellingShingle |
BC Biogeochemical Ocean Flux Study BOFS BOFS11880#5 BOFS11881#4 BOFS11882#3 BOFS11884#2 BOFS11886#4 BOFS11889#4 BOFS3C BOFS4C BOFS5C BOFS7C BOFS8C BOFS9C Box corer D184 Discovery (1962) JGOFS Joint Global Ocean Flux Study Northeast Atlantic Thomson, John Colley, S Anderson, Robert F Cook, G T MacKenzie, Angus Harkness, Douglas D Thorium and radiocarbon measurements on sediment cores from the Northseast Atlantic |
topic_facet |
BC Biogeochemical Ocean Flux Study BOFS BOFS11880#5 BOFS11881#4 BOFS11882#3 BOFS11884#2 BOFS11886#4 BOFS11889#4 BOFS3C BOFS4C BOFS5C BOFS7C BOFS8C BOFS9C Box corer D184 Discovery (1962) JGOFS Joint Global Ocean Flux Study Northeast Atlantic |
description |
Radiocarbon and 230Thexcess data from six NE Atlantic box cores are considered. The cores form a transect from the Porcupine Abyssal Plain over the East Thulean Rise to the southern end of Feni Drift. The chronology for the cores is established from bulk sediment carbonate radiocarbon data and reveals that sections exhibiting constant accumulation rates can be identified in all the cores, with rates of 3.0-3.5 cm/kyr on the plain through the Holocene and late Holocene rates of 4.3-6.6 cm/kyr elsewhere. Five out of the six cores show accumulations of more 230Thexcess than is produced in the overlying water column, with the greatest inventories (up to 225% of production) in the cores from the rise and drift. A size fraction comparison between two cores from the plain and rise reveals that the higher overall accumulation rates and 230Thexcess inventories in the off-plain cores are due to an increased fine (<5 µm) component fraction, whereas the flux of coarser material is similar to that received on the plain. This suggests that the higher fluxes of materials observed are physically (rather than biogeochemically) driven and also that drift formation has been continuously active in the late Holocene. Sections of all the cores where regular accumulation is defined by the radiocarbon data are modeled first by a linear radiocarbon age/depth model and second by a constant rain (230Thexcess)0 model prorated for the observed core inventories. These modeling approaches yield historical mass accumulation rate estimates which are generally in reasonable agreement (±30%), but the differences observed appear to be well organized in time rather than random. |
format |
Other/Unknown Material |
author |
Thomson, John Colley, S Anderson, Robert F Cook, G T MacKenzie, Angus Harkness, Douglas D |
author_facet |
Thomson, John Colley, S Anderson, Robert F Cook, G T MacKenzie, Angus Harkness, Douglas D |
author_sort |
Thomson, John |
title |
Thorium and radiocarbon measurements on sediment cores from the Northseast Atlantic |
title_short |
Thorium and radiocarbon measurements on sediment cores from the Northseast Atlantic |
title_full |
Thorium and radiocarbon measurements on sediment cores from the Northseast Atlantic |
title_fullStr |
Thorium and radiocarbon measurements on sediment cores from the Northseast Atlantic |
title_full_unstemmed |
Thorium and radiocarbon measurements on sediment cores from the Northseast Atlantic |
title_sort |
thorium and radiocarbon measurements on sediment cores from the northseast atlantic |
publisher |
PANGAEA |
publishDate |
1993 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.734066 https://doi.org/10.1594/PANGAEA.734066 |
op_coverage |
MEDIAN LATITUDE: 50.949168 * MEDIAN LONGITUDE: -21.399984 * SOUTH-BOUND LATITUDE: 47.773700 * WEST-BOUND LONGITUDE: -22.592000 * NORTH-BOUND LATITUDE: 53.703500 * EAST-BOUND LONGITUDE: -19.710700 * DATE/TIME START: 1989-07-22T00:00:00 * DATE/TIME END: 1989-07-31T00:00:00 |
long_lat |
ENVELOPE(-22.592000,-19.710700,53.703500,47.773700) |
genre |
Northeast Atlantic |
genre_facet |
Northeast Atlantic |
op_source |
Supplement to: Thomson, John; Colley, S; Anderson, Robert F; Cook, G T; MacKenzie, Angus; Harkness, Douglas D (1993): Holocene sediment fluxes in the northeast Atlantic from 230Th excess and radiocarbon measurements. Paleoceanography, 8(5), 631-650, https://doi.org/10.1029/93PA01366 |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.734066 https://doi.org/10.1594/PANGAEA.734066 |
op_rights |
CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1594/PANGAEA.73406610.1029/93PA01366 |
_version_ |
1810466013941071872 |