(Table 1) Th and U concentrations and activity ratios in deep-sea sediments at ODP Hole 105-646B
The Labrador Sea is a particularly suitable high-latitude basin for investigating U and Th behavior in deep-sea sediments. During the late Quaternary, the cyclic development and decay of huge ice sheets on adjacent land masses resulted in large-amplitude changes in sedimentation rates and organic pa...
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ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.711768 2024-09-15T18:09:40+00:00 (Table 1) Th and U concentrations and activity ratios in deep-sea sediments at ODP Hole 105-646B Hillaire-Marcel, Claude Aksu, Ali E Causse, Christiane de Vernal, Anne Ghaleb, Bassam LATITUDE: 58.209300 * LONGITUDE: -48.369100 * DATE/TIME START: 1985-10-04T08:45:00 * DATE/TIME END: 1985-10-13T21:01:00 * MINIMUM ELEVATION: -3459.0 m * MAXIMUM ELEVATION: -3459.0 m 1990 text/tab-separated-values, 352 data points https://doi.pangaea.de/10.1594/PANGAEA.711768 https://doi.org/10.1594/PANGAEA.711768 en eng PANGAEA Hillaire-Marcel, Claude; Aksu, Ali E; Causse, Christiane; de Vernal, Anne; Ghaleb, Bassam (1990): Response of Th/U in deep Labrador Sea sediments (ODP Site 646) to changes in sedimentation rates and paleoproductivities. Geology, 18(2), 162-165, https://doi.org/10.1130/0091-7613(1990)018%3C0162:ROTUID%3E2.3.CO;2 https://doi.pangaea.de/10.1594/PANGAEA.711768 https://doi.org/10.1594/PANGAEA.711768 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess 105-646B AGE error Alpha spectrometry Calculated DRILL Drilling/drill rig DSDP/ODP/IODP sample designation Joides Resolution Labrador Sea Leg105 Ocean Drilling Program ODP Sample optional label/labor no Sample code/label Thorium-230 Thorium-230/Thorium-232 ratio Thorium-230/Thorium-232 ratio error Thorium-230/Uranium-234 activity ratio standard deviation Thorium-232 Uranium-234/Uranium-238 activity ratio Uranium-238 Uranium-238/Thorium-232 ratio Uranium-238/Thorium-232 ratio error dataset 1990 ftpangaea https://doi.org/10.1594/PANGAEA.71176810.1130/0091-7613(1990)018%3C0162:ROTUID%3E2.3.CO;2 2024-07-24T02:31:30Z The Labrador Sea is a particularly suitable high-latitude basin for investigating U and Th behavior in deep-sea sediments. During the late Quaternary, the cyclic development and decay of huge ice sheets on adjacent land masses resulted in large-amplitude changes in sedimentation rates and organic paleoproductivities. The resulting magnification of U and Th response is well illustrated by high-resolution studies on piston-cored sediments from the Greenland continental rise at Ocean Drilling Program Leg 105 Site 646 spanning isotopic stages 8 to 1. Our results show a clear positive correlation of 238U/232Th ratios with organic paleoproductivity indicators (e.g., dinocyst) due to U uptake in the water column and/or during the early early diagenesis of organic matter responding to carbon fluxes and to their climate forcing. 230Th excesses over 234U exceed the theoretical value of the 230Th rain from the overlying water column, indicating lateral input possibly from the Greenland slope and shelf. Because these horizontal fluxes of 230Th may be partly controlled by physical parameters, 230Th excesses cannot be unequivocally correlated with sedimentation rates and/or productivity as reported elsewhere. In this subarctic basin characterized by low overall organic carbon burial, the 238U/232Th ratio appears to be a sensible geochemical indicator of organic activity and paleoproductivity. Dataset Greenland Labrador Sea Subarctic PANGAEA - Data Publisher for Earth & Environmental Science ENVELOPE(-48.369100,-48.369100,58.209300,58.209300) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
105-646B AGE error Alpha spectrometry Calculated DRILL Drilling/drill rig DSDP/ODP/IODP sample designation Joides Resolution Labrador Sea Leg105 Ocean Drilling Program ODP Sample optional label/labor no Sample code/label Thorium-230 Thorium-230/Thorium-232 ratio Thorium-230/Thorium-232 ratio error Thorium-230/Uranium-234 activity ratio standard deviation Thorium-232 Uranium-234/Uranium-238 activity ratio Uranium-238 Uranium-238/Thorium-232 ratio Uranium-238/Thorium-232 ratio error |
spellingShingle |
105-646B AGE error Alpha spectrometry Calculated DRILL Drilling/drill rig DSDP/ODP/IODP sample designation Joides Resolution Labrador Sea Leg105 Ocean Drilling Program ODP Sample optional label/labor no Sample code/label Thorium-230 Thorium-230/Thorium-232 ratio Thorium-230/Thorium-232 ratio error Thorium-230/Uranium-234 activity ratio standard deviation Thorium-232 Uranium-234/Uranium-238 activity ratio Uranium-238 Uranium-238/Thorium-232 ratio Uranium-238/Thorium-232 ratio error Hillaire-Marcel, Claude Aksu, Ali E Causse, Christiane de Vernal, Anne Ghaleb, Bassam (Table 1) Th and U concentrations and activity ratios in deep-sea sediments at ODP Hole 105-646B |
topic_facet |
105-646B AGE error Alpha spectrometry Calculated DRILL Drilling/drill rig DSDP/ODP/IODP sample designation Joides Resolution Labrador Sea Leg105 Ocean Drilling Program ODP Sample optional label/labor no Sample code/label Thorium-230 Thorium-230/Thorium-232 ratio Thorium-230/Thorium-232 ratio error Thorium-230/Uranium-234 activity ratio standard deviation Thorium-232 Uranium-234/Uranium-238 activity ratio Uranium-238 Uranium-238/Thorium-232 ratio Uranium-238/Thorium-232 ratio error |
description |
The Labrador Sea is a particularly suitable high-latitude basin for investigating U and Th behavior in deep-sea sediments. During the late Quaternary, the cyclic development and decay of huge ice sheets on adjacent land masses resulted in large-amplitude changes in sedimentation rates and organic paleoproductivities. The resulting magnification of U and Th response is well illustrated by high-resolution studies on piston-cored sediments from the Greenland continental rise at Ocean Drilling Program Leg 105 Site 646 spanning isotopic stages 8 to 1. Our results show a clear positive correlation of 238U/232Th ratios with organic paleoproductivity indicators (e.g., dinocyst) due to U uptake in the water column and/or during the early early diagenesis of organic matter responding to carbon fluxes and to their climate forcing. 230Th excesses over 234U exceed the theoretical value of the 230Th rain from the overlying water column, indicating lateral input possibly from the Greenland slope and shelf. Because these horizontal fluxes of 230Th may be partly controlled by physical parameters, 230Th excesses cannot be unequivocally correlated with sedimentation rates and/or productivity as reported elsewhere. In this subarctic basin characterized by low overall organic carbon burial, the 238U/232Th ratio appears to be a sensible geochemical indicator of organic activity and paleoproductivity. |
format |
Dataset |
author |
Hillaire-Marcel, Claude Aksu, Ali E Causse, Christiane de Vernal, Anne Ghaleb, Bassam |
author_facet |
Hillaire-Marcel, Claude Aksu, Ali E Causse, Christiane de Vernal, Anne Ghaleb, Bassam |
author_sort |
Hillaire-Marcel, Claude |
title |
(Table 1) Th and U concentrations and activity ratios in deep-sea sediments at ODP Hole 105-646B |
title_short |
(Table 1) Th and U concentrations and activity ratios in deep-sea sediments at ODP Hole 105-646B |
title_full |
(Table 1) Th and U concentrations and activity ratios in deep-sea sediments at ODP Hole 105-646B |
title_fullStr |
(Table 1) Th and U concentrations and activity ratios in deep-sea sediments at ODP Hole 105-646B |
title_full_unstemmed |
(Table 1) Th and U concentrations and activity ratios in deep-sea sediments at ODP Hole 105-646B |
title_sort |
(table 1) th and u concentrations and activity ratios in deep-sea sediments at odp hole 105-646b |
publisher |
PANGAEA |
publishDate |
1990 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.711768 https://doi.org/10.1594/PANGAEA.711768 |
op_coverage |
LATITUDE: 58.209300 * LONGITUDE: -48.369100 * DATE/TIME START: 1985-10-04T08:45:00 * DATE/TIME END: 1985-10-13T21:01:00 * MINIMUM ELEVATION: -3459.0 m * MAXIMUM ELEVATION: -3459.0 m |
long_lat |
ENVELOPE(-48.369100,-48.369100,58.209300,58.209300) |
genre |
Greenland Labrador Sea Subarctic |
genre_facet |
Greenland Labrador Sea Subarctic |
op_relation |
Hillaire-Marcel, Claude; Aksu, Ali E; Causse, Christiane; de Vernal, Anne; Ghaleb, Bassam (1990): Response of Th/U in deep Labrador Sea sediments (ODP Site 646) to changes in sedimentation rates and paleoproductivities. Geology, 18(2), 162-165, https://doi.org/10.1130/0091-7613(1990)018%3C0162:ROTUID%3E2.3.CO;2 https://doi.pangaea.de/10.1594/PANGAEA.711768 https://doi.org/10.1594/PANGAEA.711768 |
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.71176810.1130/0091-7613(1990)018%3C0162:ROTUID%3E2.3.CO;2 |
_version_ |
1810447241501999104 |