Evaluating Zr/Rb Ratio From XRF Scanning as an Indicator of Grain-Size Variations of Glaciomarine Sediments in the Southern Ocean
The ln(Zr/Rb) count ratio derived from X-ray fluorescence (XRF) core scanning holds potential as a high-resolution tracer for grain-size variations of glaciomarine sediments, and hence current strength. To evaluate this approach, we conducted high-resolution grain-size measurements, together with Rb...
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Language: | English |
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Online Access: | http://ir.qdio.ac.cn/handle/337002/169305 https://doi.org/10.1029/2020GC009350 |
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ftchinacasciocas:oai:ir.qdio.ac.cn:337002/169305 2023-05-15T13:50:09+02:00 Evaluating Zr/Rb Ratio From XRF Scanning as an Indicator of Grain-Size Variations of Glaciomarine Sediments in the Southern Ocean Wu, Li Wilson, David J. Wang, Rujian Yin, Xuebo Chen, Zhihua Xiao, Wenshen Huang, Mengxue 2020-11-01 http://ir.qdio.ac.cn/handle/337002/169305 https://doi.org/10.1029/2020GC009350 英语 eng AMER GEOPHYSICAL UNION GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS http://ir.qdio.ac.cn/handle/337002/169305 doi:10.1029/2020GC009350 bottom currents glaciomarine sediment grain‐ size iceberg rafted debris Southern Ocean XRF core scanning Zr Rb Geochemistry & Geophysics ANTARCTIC ICE-SHEET SORTABLE SILT PALEOCURRENT SPEED CONTINENTAL-SLOPE LABRADOR CURRENT EAST ANTARCTICA ATMOSPHERIC CO2 ROSS SEA CHINA CORE 期刊论文 2020 ftchinacasciocas https://doi.org/10.1029/2020GC009350 2022-06-27T05:43:20Z The ln(Zr/Rb) count ratio derived from X-ray fluorescence (XRF) core scanning holds potential as a high-resolution tracer for grain-size variations of glaciomarine sediments, and hence current strength. To evaluate this approach, we conducted high-resolution grain-size measurements, together with Rb and Zr measurements by XRF core scanning and inductively coupled plasma-mass spectrometry (ICP-MS), on a series of sediment cores from different regions of the Southern Ocean. Downcore changes of the ln(Zr/Rb) count ratio from XRF core scanning are consistent with Zr/Rb concentration ratios derived from ICP-MS analyses, even though Rb and Zr counts deviate significantly from concentrations due to specimen and matrix effects. The ln(Zr/Rb) count ratio displays discrepancies with the bulk mean grain-size, but correlates well with the mean grain-size of the sediment fractions that do not include unsorted sand delivered by ice-rafting. These observations are supported by evidence from a grain-size separation experiment, which indicates that Zr and Rb are concentrated in different grain-size fractions. Consistent with its lack of sensitivity to coarse grain-size fractions derived from ice-rafting, the ln(Zr/Rb) ratio records similar trends to the sortable silt percent (SS%) and sortable silt mean (SS over bar ) grain-size. Universal gradients exist in plots of SS% versus ln(Zr/Rb), and SS over bar versus ln(Zr/Rb), such that the ln(Zr/Rb) ratio provides a convenient way to estimate the magnitude of changes in SS% and SS over bar . Overall, our results support the use of the ln(Zr/Rb) ratio as an indicator of bottom current strength in cases where the sediment is current-sorted. Report Antarc* Antarctic Antarctica East Antarctica Ice Sheet Iceberg* Ross Sea Southern Ocean Institute of Oceanology, Chinese Academy of Sciences: IOCAS-IR Antarctic East Antarctica Ross Sea Southern Ocean Geochemistry, Geophysics, Geosystems 21 11 |
institution |
Open Polar |
collection |
Institute of Oceanology, Chinese Academy of Sciences: IOCAS-IR |
op_collection_id |
ftchinacasciocas |
language |
English |
topic |
bottom currents glaciomarine sediment grain‐ size iceberg rafted debris Southern Ocean XRF core scanning Zr Rb Geochemistry & Geophysics ANTARCTIC ICE-SHEET SORTABLE SILT PALEOCURRENT SPEED CONTINENTAL-SLOPE LABRADOR CURRENT EAST ANTARCTICA ATMOSPHERIC CO2 ROSS SEA CHINA CORE |
spellingShingle |
bottom currents glaciomarine sediment grain‐ size iceberg rafted debris Southern Ocean XRF core scanning Zr Rb Geochemistry & Geophysics ANTARCTIC ICE-SHEET SORTABLE SILT PALEOCURRENT SPEED CONTINENTAL-SLOPE LABRADOR CURRENT EAST ANTARCTICA ATMOSPHERIC CO2 ROSS SEA CHINA CORE Wu, Li Wilson, David J. Wang, Rujian Yin, Xuebo Chen, Zhihua Xiao, Wenshen Huang, Mengxue Evaluating Zr/Rb Ratio From XRF Scanning as an Indicator of Grain-Size Variations of Glaciomarine Sediments in the Southern Ocean |
topic_facet |
bottom currents glaciomarine sediment grain‐ size iceberg rafted debris Southern Ocean XRF core scanning Zr Rb Geochemistry & Geophysics ANTARCTIC ICE-SHEET SORTABLE SILT PALEOCURRENT SPEED CONTINENTAL-SLOPE LABRADOR CURRENT EAST ANTARCTICA ATMOSPHERIC CO2 ROSS SEA CHINA CORE |
description |
The ln(Zr/Rb) count ratio derived from X-ray fluorescence (XRF) core scanning holds potential as a high-resolution tracer for grain-size variations of glaciomarine sediments, and hence current strength. To evaluate this approach, we conducted high-resolution grain-size measurements, together with Rb and Zr measurements by XRF core scanning and inductively coupled plasma-mass spectrometry (ICP-MS), on a series of sediment cores from different regions of the Southern Ocean. Downcore changes of the ln(Zr/Rb) count ratio from XRF core scanning are consistent with Zr/Rb concentration ratios derived from ICP-MS analyses, even though Rb and Zr counts deviate significantly from concentrations due to specimen and matrix effects. The ln(Zr/Rb) count ratio displays discrepancies with the bulk mean grain-size, but correlates well with the mean grain-size of the sediment fractions that do not include unsorted sand delivered by ice-rafting. These observations are supported by evidence from a grain-size separation experiment, which indicates that Zr and Rb are concentrated in different grain-size fractions. Consistent with its lack of sensitivity to coarse grain-size fractions derived from ice-rafting, the ln(Zr/Rb) ratio records similar trends to the sortable silt percent (SS%) and sortable silt mean (SS over bar ) grain-size. Universal gradients exist in plots of SS% versus ln(Zr/Rb), and SS over bar versus ln(Zr/Rb), such that the ln(Zr/Rb) ratio provides a convenient way to estimate the magnitude of changes in SS% and SS over bar . Overall, our results support the use of the ln(Zr/Rb) ratio as an indicator of bottom current strength in cases where the sediment is current-sorted. |
format |
Report |
author |
Wu, Li Wilson, David J. Wang, Rujian Yin, Xuebo Chen, Zhihua Xiao, Wenshen Huang, Mengxue |
author_facet |
Wu, Li Wilson, David J. Wang, Rujian Yin, Xuebo Chen, Zhihua Xiao, Wenshen Huang, Mengxue |
author_sort |
Wu, Li |
title |
Evaluating Zr/Rb Ratio From XRF Scanning as an Indicator of Grain-Size Variations of Glaciomarine Sediments in the Southern Ocean |
title_short |
Evaluating Zr/Rb Ratio From XRF Scanning as an Indicator of Grain-Size Variations of Glaciomarine Sediments in the Southern Ocean |
title_full |
Evaluating Zr/Rb Ratio From XRF Scanning as an Indicator of Grain-Size Variations of Glaciomarine Sediments in the Southern Ocean |
title_fullStr |
Evaluating Zr/Rb Ratio From XRF Scanning as an Indicator of Grain-Size Variations of Glaciomarine Sediments in the Southern Ocean |
title_full_unstemmed |
Evaluating Zr/Rb Ratio From XRF Scanning as an Indicator of Grain-Size Variations of Glaciomarine Sediments in the Southern Ocean |
title_sort |
evaluating zr/rb ratio from xrf scanning as an indicator of grain-size variations of glaciomarine sediments in the southern ocean |
publisher |
AMER GEOPHYSICAL UNION |
publishDate |
2020 |
url |
http://ir.qdio.ac.cn/handle/337002/169305 https://doi.org/10.1029/2020GC009350 |
geographic |
Antarctic East Antarctica Ross Sea Southern Ocean |
geographic_facet |
Antarctic East Antarctica Ross Sea Southern Ocean |
genre |
Antarc* Antarctic Antarctica East Antarctica Ice Sheet Iceberg* Ross Sea Southern Ocean |
genre_facet |
Antarc* Antarctic Antarctica East Antarctica Ice Sheet Iceberg* Ross Sea Southern Ocean |
op_relation |
GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS http://ir.qdio.ac.cn/handle/337002/169305 doi:10.1029/2020GC009350 |
op_doi |
https://doi.org/10.1029/2020GC009350 |
container_title |
Geochemistry, Geophysics, Geosystems |
container_volume |
21 |
container_issue |
11 |
_version_ |
1766253126714654720 |