Neodymium isotopic signature of the Ross Sea Water characterized

The first seawater neodymium isotopic compositions (εNd) and neodymium concentrations [Nd] profiles across the South Pacific circum-Antarctic fronts have been published recently (Basak et al., 2015, see reference below). Thanks to this exceptional GEOTRACES-compliant data, collected on R/V Polarstern cruise PS75, authors characterize the εNd signature of Ross Sea Bottom Water (εNd ~ -7) and show that meridional Nd concentrations changes follow the density structure of the South Pacific. The latter suggests a lateral transport component for the processes controlling Nd concentrations in the Southern Ocean rather than vertical processes.

15 Basak l
Figure: Distribution of εNd and [Nd] across the South Pacific frontal system (map) from the Ross Sea into the southeast Pacific. Left: Distribution of dissolved εNd; right: Distribution of [Nd] with neutral density contours. Click on the following links to view the figures larger: map, distribution of dissolved εNd and distribution of [Nd].

Reference:

Basak, C., Pahnke, K., Frank, M., Lamy, F., & Gersonde, R. (2015). Neodymium isotopic characterization of Ross Sea Bottom Water and its advection through the southern South Pacific. Earth and Planetary Science Letters, 419, 211–221. doi:10.1016/j.epsl.2015.03.011

Latest highlights

Another step towards replacing NOBIAS Chelate PA-1

Kanna and his colleagues successfully carried out the quantitative pre-concentration of seven trace metals…

Neodymium budget in the Arabian Sea is governed by a combination of water mass advection and dominant boundary exchange processes

Karri and Singh established the neodymium concentrations and isotopic compositions along a North-South section in the eastern Arabian Sea…

Cesium isotopes confirm that hydrogenetic iron-manganese crusts are precipitating from the oxygen minimum zone to abyssal depths

Li and co-authors provide new insights on the formation mechanism of ferromanganese crusts.

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…

Rechercher