Evaluating Zr/Rb Ratio From XRF Scanning as an Indicator of Grain-Size Variations of Glaciomarine Sediments in the Southern Ocean

doi:10.1029/2020GC009350

CORC > 海洋研究所 > 中国科学院海洋研究所

	Evaluating Zr/Rb Ratio From XRF Scanning as an Indicator of Grain-Size Variations of Glaciomarine Sediments in the Southern Ocean
	Wu, Li 2; Wilson, David J.3; Wang, Rujian 2; Yin, Xuebo 1,4; Chen, Zhihua 5; Xiao, Wenshen 2; Huang, Mengxue 2
刊名	GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS
	2020-11-01
卷号	21 期号:11 页码:26
关键词	bottom currents glaciomarine sediment grain‐ size iceberg rafted debris Southern Ocean XRF core scanning Zr Rb
DOI	10.1029/2020GC009350
通讯作者	Wang, Rujian(rjwang@tongji.edu.cn)
英文摘要	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.
资助项目	National Natural Science Foundation of China ; Postdoctoral Research Foundation of China[41806223] ; Postdoctoral Research Foundation of China[2018M632158] ; Postdoctoral Research Foundation of China[41776191] ; Postdoctoral Research Foundation of China[41676191] ; Ministry of Natural Resources of China ; National Oceanic Administration's Polar Expedition Office[RFSOCC20202022] ; National Oceanic Administration's Polar Expedition Office[16] ; National Oceanic Administration's Polar Expedition Office[17]
WOS研究方向	Geochemistry & Geophysics
语种	英语
出版者	AMER GEOPHYSICAL UNION
WOS记录号	WOS:000595790900027
内容类型	期刊论文
源URL	[http://ir.qdio.ac.cn/handle/337002/169306]
专题	中国科学院海洋研究所
通讯作者	Wang, Rujian
作者单位	1.Chinese Acad Sci, Inst Oceanol, Qingdao, Peoples R China 2.Tongji Univ, State Key Lab Marine Geol, Shanghai, Peoples R China 3.Univ London, Univ Coll London & Birkheck, Inst Earth & Planetary Sci, London, England 4.Qingdao Sparta Anal & Test Co Ltd, Qingdao, Peoples R China 5.State Ocean Adm, Inst Oceanog 1, Qingdao, Peoples R China
推荐引用方式 GB/T 7714	Wu, Li,Wilson, David J.,Wang, Rujian,et al. Evaluating Zr/Rb Ratio From XRF Scanning as an Indicator of Grain-Size Variations of Glaciomarine Sediments in the Southern Ocean[J]. GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS,2020,21(11):26.
APA	Wu, Li.,Wilson, David J..,Wang, Rujian.,Yin, Xuebo.,Chen, Zhihua.,...&Huang, Mengxue.(2020).Evaluating Zr/Rb Ratio From XRF Scanning as an Indicator of Grain-Size Variations of Glaciomarine Sediments in the Southern Ocean.GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS,21(11),26.
MLA	Wu, Li,et al."Evaluating Zr/Rb Ratio From XRF Scanning as an Indicator of Grain-Size Variations of Glaciomarine Sediments in the Southern Ocean".GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS 21.11(2020):26.