Geochemistry, Geophysics, Geosystems Supporting Information for
Efficient extraction of past seawater Pb and Nd isotope signatures from Southern Ocean derived bulk sediments
H. Huang1, M. Gutjahr1, G. Kuhn2, Ed C. Hathorne1 and A. Eisenhauer1
1GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany.
2Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven, Germany.
Corresponding author: Huang Huang (huanghuang@mail.sysu.edu.cn)
Contents of this file
Table captions from S1 to S9 Tables S7 to S9
Introduction
Supporting information for this manuscript include: 1) mass bias-corrected and normalised leaching isotopic and concentration data; 2) porewater isotopic data; 3) details of the sediment sampling locations for leaching lest;
4) description of Ion chromatography for separating Pb from Mg(OH)2
precipitates and 3) reproducibility information of Pb and Nd isotopic ratio measurements. The Table S1 to S6 are shown in a separate Excel file due to their large sizes.
1
Table S1.Sediment sampling locations used during this study.
Table S2.Isotopic compositions and concentrations data in the leachate with and without MgCl2 prewash.
Table S3.Isotopic compositions and concentrations data in the leachate with different chelate ligands.
Table S4.Isotopic compositions and concentrations data in the leachate of different treatment time.
Table S5.Isotopic compositions and concentrations data of Pb and Nd in the CTD seawater and MUC bottom water.
Table S6.Porewater and leachate Nd and Pb isotopic compositions of the MUC samples.
2
volume Eluate Stage
1 mL 1 M HNO3 Clean column
1 mL Milli Q water Clean column
0.5 mL 2% HNO3 Load resin
0.1 mL AG1X8 resin, 100–200 mesh Load resin
0.2 mL 2 M HBr/0.1 M HF Pre-conditioning
0.2 mL 2 M HBr/0.1 M HF Pre-conditioning
3x 2 mL In 2 M HBr/0.1 M HF Load sample
0.5 mL 2 M HBr/0.1 M HF Elute matrix (collect Nd)
0.5 mL 2 M HBr/0.1 M HF Elute matrix (collect Nd)
0.1 mL 0.5 M HNO3/0.2 M HBr Elute matrix (collect Nd) 0.1 mL 0.5 M HNO3/0.2 M HBr Elute matrix (collect Nd) 0.15 mL 0.5 M HNO3/0.2 M HBr Elute matrix (collect Nd) 0.15 mL 0.5 M HNO3/0.2 M HBr Elute matrix (collect Nd)
0.15 mL 0.5 M HNO3/0.03 M HBr Collect pure Pb
0.3 mL 0.5 M HNO3/0.03 M HBr Collect pure Pb
0.2 mL 0.5 M HNO3/0.03 M HBr Collect pure Pb
Table S7. Column purification procedure for the separation of Pb co- precipitated in Mg(OH)2 from MUC bottom water and CTD seawater.
3
206Pb/204Pb 207Pb/204Pb 208Pb/204Pb 208Pb/206Pb 207Pb/206Pb 208Pb/207Pb Leachate
standards (n=169)
28ppb Pb:7ppb Tl
NOD-A-1 18.959 15.679 38.933 2.0535 0.8270 2.4831
2 S.D. 0.009 0.010 0.035 0.0009 0.0002 0.0006
Seawater standards (n=16)
1ppb Pb:1ppb Tl
NOD-A-1 18.960 15.680 38.942 2.0539 0.8270 2.4836
2 S.D. 0.015 0.015 0.043 0.0013 0.0003 0.0012
Porewater standards (n=11)
20ppt Pb:20ppt Tl
NOD-A-1 18.864 15.587 38.558 2.0486 0.8256 2.4825
2 S.D. 1.924 1.467 3.614 0.0145 0.0074 0.0185
Literature value
Baker et
al. 2004 18.964 15.685 38.956 2.0543 0.8271
2 S.D. 0.001 0.001 0.003 0.0001 0.0000
Table S8. The reproducibility of the secondary standard USGS NOD-A-1 for seawater, porewater and leachate Pb isotopic compositions.
4
143Nd/144Nd εNd
Regular standards
(n=98) 50 ppb Nd NIST 3135a 0.512450 -3.67
2 S.D. 0.000010 0.20
MUC bottom water standards
(n=5)
2 ppb Nd
NIST 3135a 0.512436 -3.94
2 S.D. 0.000064 1.25
Table S9. Reproducibility of the secondary standard NIST 3135a for seawater and leachate Nd isotopic compositions. Note that NIST 3135a standard is only certified for its Nd concentration and not for its isotopic composition.
