Twenty seawater profiles and twenty core-top 231-protactinium (231Pa) and 230-thorium (230Th) analyses were realised by Ng and colleagues (2020, see reference below) along five depth transects across the northern tropical Atlantic open ocean. Among them, eighteen seawater-sediment pairs from nearby sites were compared. A thorough examination of this coupling associated to published data of 231Pa and 230Th in the North Atlantic Ocean, allow the authors to i) confirm the dominance of the 231Pa-export signal in the deep Atlantic associated with the southward advection of North Atlantic Deep Water (NADW) but also ii) observe contrasting local increases of sedimentary 231Pa/230Th above the production ratio, with higher values at intermediate depths (0.5–1.5 km) and in the eastern and mid-Atlantic sites. These last observations reflect either an additional input of 231Pa to the intermediate depths, or enhanced 231Pa scavenging at the eastern and mid-Atlantic sites, and/or the influence of boundary scavenging near the eastern margin.
Ng, H. C., Robinson, L. F., Rowland, G. H., Chen, S. S., & McManus, J. F. (2020). Coupled analysis of seawater and sedimentary 231Pa/230Th in the tropical Atlantic. Marine Chemistry, 227, 103894. DOI: https://doi.org/10.1016/J.MARCHEM.2020.103894