The power of combining geochemical tracer data with direct current measurements

By using an original combination between seawater Rare Earth Elements  (REE) concentrations and direct physical oceanographic observations (e.g., current velocity data), Behrens and collaborators (2020, see reference below) characterised the geochemical composition, origin and pathways of the complex surface and upper layer currents of the Tropical Western Pacific Ocean. They show that surface water enrichments are largely derived from the basaltic Papua New Guinea margin sediments and/or the Sepik river solid discharge, while the Sepik dissolved input represents less than 3.5% input of the neodymium flux leaving the Solomon Sea by the Vitiaz Strait. The combination also allows discussing the temporal variability of the REE sources in this area.

Figure: (a) Transect of surface currents and (b) plot of (Yb/Er)N vs. 1/[Nd] of surface waters from stations sampled along the SEC (inverted triangle, Behrens et al., 2018a) via the Vitiaz Strait (triangle, Pham et al., 2019) to the equatorial SC (dot, this study) along with (Yb/Er)N of Papua New Guinea (PNG) sources (black squares, volcanic rocks, Sepik River water and sediment, Sholkovitz et al., 1999; Woodhead et al., 2010) indicating input from PNG to the equatorial SC.

Reference:

Behrens, M. K., Pahnke, K., Cravatte, S., Marin, F., & Jeandel, C. (2020). Rare earth element input and transport in the near-surface zonal current system of the Tropical Western Pacific. Earth and Planetary Science Letters, 549, 116496. DOI: https://doi.org/10.1016/J.EPSL.2020.116496

Latest highlights

Science Highlights

Dissolved iron and manganese fates reveal processes along the hydrothermal TAG plume

González-Santana and co-workers performed high-spatial resolution analyses of dissolved iron and manganese samples collected at the Mid Atlantic Ridge

20.10.2020

Science Highlights

Loss of old Arctic sea ice increases methylmercury concentrations

Researchers from the SCRIPPS, the Stockholm Natural Museum and the Mediterranean Institute of Oceanography show the importance of sea ice composition on methylmercury budgets

02.09.2020

Science Highlights

Estimating Atmospheric Trace Element Deposition Over the Global Ocean

A recently developed method based on the natural radionuclide beryllium-7 has provided a means to estimate the bulk atmospheric trace element deposition velocity

Science Highlights

Dissolved gallium unravels Pacific and Atlantic waters in the Arctic Ocean

Whitmore and co-workers demonstrate that the dissolved gallium distribution provide a better water source deconvolution than the nutrient tracers

22.07.2020

Rechercher