The sedimentary flux of dissolved rare earth elements to the ocean

This work highlights the importance of the sedimentary source of dissolved Rare Earth Elements (REE) to the oceanic waters. Indeed, strong subsurface REE concentration maxima are evidenced in pore fluids in core tops collected along the Californian and Oregon margins (above, within and below the oxygen minimum zone of the North-East Pacific). Diffusive flux of neodymium (Nd) out of the sediments matches preceding estimates of the “missing term” of Nd in modeled global Nd budgets. Also interesting, the decoupling between REE and iron fates in these pore fluids…

15 Abbott l
Figure: Site locations and the associated pore fluid profiles. Neodymium (Nd) and iron (Fe) profiles plotted against sediment depth in pore fluids from (clockwise from top left) the Oregon shelf, the Oregon slope, and the California shelf. Filled symbols represent sites unique to this study and open symbols are sites from prior expeditions. Rivers are indicated in blue and labeled. Click here to view the figure larger.

Reference:

Abbott, A. N., Haley, B. A., McManus, J., & Reimers, C. E. (2015). The sedimentary flux of dissolved rare earth elements to the ocean. Geochimica et Cosmochimica Acta, 154, 186–200. doi:10.1016/j.gca.2015.01.010. Please click here to access the paper.

Latest highlights

Continuous record of the Antarctic Circumpolar Current latitude over the last glacial-interglacial cycles

The meridional positions of the oceanic fronts separating subtropical and Antarctic waters are key to constraining the mechanisms that drive the degassing of deeply-stored CO2 at the end of the glacial periods…

23 Million Years of iron sources reconstructed in the Northwest Pacific Ocean using iron isotopes in a ferromanganese crust

Using iron isotopes and elemental records, Chu and co-workers analysed an iron-manganese crust recovered from the Hongyan Seamount, and reconstructed the sources of dissolved Fe to the Northwest Pacific Ocean…

Variability of the past deep-water masses in the Arabian Sea over the last 41ka

Shukla and colleagues propose a high-resolution authigenic ƐNd record measured from a sediment core located in the eastern Arabian Sea…

Arctic outflows to Davis Strait and the Labrador Sea traced by radionuclide distributions

This study demonstrates that Arctic outflows through the Canadian Arctic Archipelago play a much more significant role than previously recognised.

Rechercher