Analytical Methods: Dissolved Fe, Zn, Cu and Cd in the seawater samples were analyzed using Mg(OH)2 coprecipitation ID-ICPMS (isotope dilution - Inductively Coupled Plasma Mass Spectrometry) (Wu and Boyle, 1997; 1998). Dissolved Mn was measured using the same method modified by Boyle et al (2005). The precision and analytical blanks vary for each station and are provided together with each profile in the submitted file.
References: Wu J. and Boyle E. A. (1997) Low blank preconcentration technique for the determination of lead, copper, and cadmium in small-volume seawater samples by isotope dilution ICPMS. Anal. Chem. 69, 2464-2470.
Wu J. and Boyle E. A. (1998) Determination of iron in seawater by isotope dilution inductively couple plasma mass spectrometry after Mg(OH)2 coprecipitation. Anal. Chim. Acta 367, 183-191.
Boyle E. A., Bergquist R. A., Hayser R. A. and Mahowald N. (2005) Iron, manganese, and lead at Hawaii ocean time-series station ALOHA: temporal variability in an intermediate water hydrothermal plume. Geochim. Cosmochim. Acta 69, 933-952.
BCO-DMO edits:
- Depth and Pressure occupied the 'Depth(m)' column. To be consistent, where necessary corrected to Depth in meters. (information from GT-C Bottle file)
- Cadmium concentration reported in both nM and pM. PI said change to pM.
- Cadmium concentration was displayed without decimal precision when submitted, although the Excel cells had 16 decimals of precision. DMO changed to two decimal places to be consistent with other Cd submitted. Submitted Cd blanks have zero to two decimals.
- Two portions of KN204-01, KN204-01A and KN204-01B, were reported as 'cruise_part'.
- Station nominal locations were provided by Chief Scientists because casts were not all in the same place as the original station location. This dataset had no cast information.
- 'nd's put in blank cells.
- KN199-04:
station 7 depth changed to 751 from 757
station 10 depth changed to 800 from 780
station 12 Wu depths were Measures' pressure, so I changed the numbers to match Measures depths, according to instructions from the PI.
Reference Concentrations