Xie and co-workers (2017, see reference below) report cadmium (Cd) isotopic compositions from five stations and 15 tow-Fish surface waters from 50ºS to the equator along GEOTRACES GA02 Leg 3. Along this transect, the coupled Cd concentrations and Cd isotopes reflect classical behaviour dominated by preferential uptake of light Cd by the biological species at the surface, release in the twilight zone and water mass mixing deeper. Surprisingly, ε112/110Cd displays a "flattening off" pattern in the surface and subsurface waters of stations north of the Subantarctic Front, while Cd concentrations decrease to low levels; this observation can be extended to the global Cd isotope dataset at hand for Cd concentrations below a nominal value of 0.1 nmol kg-1. Two explanations are proposed for this behaviour: 1) either Cd is bound by organic detritus, colloids or ligands and passes the 0.2μm filtration of the samples, products which could dominate ε112/110Cd over that of the dissolved pool; or 2) the ε112/110Cd values result from a simple open system, steady-state model for the (sub)surface layer, fed with an in-flux of Cd from deeper waters.

17 Xie
Map of the five super stations (color circles) and tow-Fish surface sites (crosses) for Cd isotopes along GA02 Leg 3 (Left), and Cd isotope systematics in the western South Atlantic (Middle) and the global ocean (right). Color circles for profile samples, and open circles for tow-Fish seawater samples (this study). In the right-hand panel: grey diamonds – North Atlantic (Boyle et al., 2012; Conway and John 2015a; John and Conway, 2014); open triangles – North (Conway and John, 2015b; Ripperger et al., 2007) and South Pacific (New Zealand (Gault-Ringold et al., 2012), South China Sea and Philippine Sea (Yang et al., 2012, 2014)); open squares – Southern Ocean (Abouchami et al., 2011, 2014; Xue et al., 2013). Red dashed lines in the middle and right-hand panels schematically highlight the evolution of seawater e112/110Cd toward low Cd concentrations. Error bars (2s) are shown. Click here to view the figure larger.


Xie, R. C., Galer, S. J. G., Abouchami, W., Rijkenberg, M. J. A., de Baar, H. J. W., De Jong, J., & Andreae, M. O. (2017). Non-Rayleigh control of upper-ocean Cd isotope fractionation in the western South Atlantic. Earth and Planetary Science Letters (Vol. 471). DOI: 10.1016/j.epsl.2017.04.024

Filter by Keyword

Aerosol Inputs Aerosols Aluminium Analysis Anoxia Antarctic Geology Arctic Ocean Arsenic Artificial Intelligence Atlantic Ocean Atmospheric Dynamic Barium Barium Isotopes Behavior Benthic Beryllium BioGEOSCAPES Biological Pump Black Sea Boundary Exchange Boundary Scavenging Budget Cadmium Cadmium Isotopes Cadmium Sulfide Chromium Chronium Isotopes Circulation Climate Change CO2 Degassing Coastal Area Cobalt Copper Copper Isotopes Cycles Data Compilation Deep Water Dissolved Concentrations Distribution Distribution Coefficient Ecosystem Eddy Kinetic Energy Environmental Change Estuaries Experiments Export Fluxes Fate Fertilisation Fractionation Gadolinium Gallium Global Scale Hafnium Hafnium Isotopes Helium Helium Isotopes Hydrothermal Hypoxia Ice ICPMS Indian Ocean Inputs Intercalibration Intercomparison International Polar Year Iodine Iron Iron Isotopes Iron Sulfide Isotopes Land Ocean Inputs Lanthanum Lead Lead Isotopes Limitation Lithogenic Macronutriments Mammals Manganese Mediterranean Sea Mercury Mesopelagic Mesoscale Transport Methylmercury Microbial Micronutriments Modelling Multiple TEIs Neodymium Neodymium Isotopes Nepheloids Nickel Nitrate Nitrogen Nutrients Organic Matter Osmium Oxygen Pacific Ocean Paleoceanography Paleocirculation Particle Fluxes Particles Particulate Organic Carbon Phosphate Phosporus Phytoplankton Pitzer Equations Precipitation Procedure Processes Productivity Protactinium Protocol Proxy Radium Radium Isotopes Rare Earth Elements Red Sea Remineralization Residence Times River SAFE Samples Scandium Scavenging Sea Ice Sediments Shelf Silicon Silicon Isotopes Southern Ocean Speciation Submarine Ground Water Discharge Surface Waters Thorium Thorium Isotopes Thorium-Protactinium Time Series Total Hg Transmissiometer Uranium Uranium Isotopes Yttrium Zinc Zinc Isotopes

 Data Product (IDP2017)


 Data Assembly Centre (GDAC)


Subscribe Mailing list

Contact us

To get a username and password, please contact the GEOTRACES IPO.

This site uses cookies to offer you a better browsing experience. Find out more on how we use cookies and how you can change your settings.