Fe2+ in Ice Cores as a New Potential Proxy to Detect Past Volcanic Eruptions
François Burgay, Tobias Erhardt, Damiano Della Lunga, Camilla Marie Jensen, Andrea Spolaor, Paul Vallelonga, Hubertus Fischer, Carlo Barbante
Science of the Total Environment
Layers from past volcanic eruptions are of great interest in ice core research because they can be used to date and synchronize ice cores. Typically, sulphate is used as the main indicator for such volcanic layers. However, sulphate quantification methods easily applicable to high-resolution ice core studies are lacking.
Thus, Burgay and co-workers set out to demonstrate that iron (i.e., Fe2+) is another suitable proxy for fingerprinting past volcanic eruptions. They present a new high-resolution continuous flow analysis chemiluminescence method for the continuous determination of Fe2+ in ice cores (CFA-CL-Fe2+).
In this study, an icpTOF R was used to determine the total iron content, present both as soluble and particulate fractions. For this, the icpTOF was directly connected to the meltwater stream of the CFA system. To enable the determination of iron using the isotope 56Fe, which is known to be compromised by an interference of 40Ar16O, the collision/reaction cell (Q-Cell) was used with a mixture of H2 and He.
With their combined CFA-CL-Fe2+ and ICP-TOFMS datasets, the authors present the first complete continuous iron chemical speciation dataset ever to be retrieved from an ice core.