Novel isotopic tracers in Marine Sciences: Neodymium and boron analysis at nanogram levels

VII International Symposium on Marine Sciences (ISMS 2020), 1-3 July 2020 (Barcelona).-- 2 pages

Recent advancements in mass spectrometry allow the possibility to measure precise and accurate isotopic ratios of different elements present in the ocean with very low natural abundances (nanograms). This opens a new realm of possibilities in the Marine Sciences. In this regard, neodymium and boron isotopes are becoming nowadays solid tools to study the ocean both during present day and past times. Neodymium isotopes in seawater are used as tracers of modern ocean circulation, whereas the analysis of marine sedimentary substrates (foraminifera, corals and fish teeth) provides information about the effect of past climate changes on ocean circulation. Boron speciation in seawater is determined by the pH, leading to a modification of the B(0H)4− isotopic signature as a result of ocean acidification processes. Since B(0H)4− is incorporated into carbonates, boron isotopes in foraminifers and corals are used to reconstruct past changes in ocean acidification and the associated atmospheric pCO2 levels. Owing to the small size of someof these samples and the high precision of isotope ratio results required for these applications, special care must be taken during sample preparation and analysis in order to obtain high quality results. This is now possible at the University of Barcelona thanks to two newly available facilities (LIRA and PANTHALASSA). LIRA (Laboratori d’Isòtops Radiogènics i Ambientals) is a metal-free clean laboratory with certified ISO 5 air quality, whereas PANTHALASSA is the last generation Plasma 3 Multi-Collector Inductively Coupled Plasma Mass Spectrometer. With these two facilities we have setup methods for the high-precision isotopic analysis of neodymium and boron in samples containing only a few nanograms of these elements

This work has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (ERC-Consolidator project TIMED, Grant agreement No. 683237). The authors also thank the financial support from the MINECO (CHIMERA project, CTM2016-75411-R)

Peer reviewed