Rare earth elements and Nd isotopes tracing water mass mixing and particle-seawater interactions in the SE Atlantic

The εNd composition behaves conservatively in intermediate and deep waters, while input processes affect the isotopic signal of subtropical surface waters and Weddell Gyre bottom waters. An Indian Ocean and an Atlantic variety of AAIW have been isotopically differentiated (εNd = −9.3 ± 0.3 and εNd = −8.0 ± 0.5, respectively). Homogeneous signatures characterize circumpolar waters (εNd from −8.2 to −8.4 for CDW). A binary mixing model has been used to assess the contribution of undiluted NADW reaching southern latitudes.