Diatom chemistry as a potential paleoproxy for sea surface conditions

Diatoms are responsible for over 40% of the total primary production and yet they are not a leading paleo-proxy. Instead, over the past few decades, foraminiferal-based proxies have dominated climate reconstruction research. Developments in analytical techniques have made it possible to look at chemical characteristics of samples on nanometer scale and may thus improve our understanding of the nature of diatoms. In this study we aim to identify changes in elemental ratios related to environmental changes, in both the diatom frustule itself and the occluded organic matter. Here we present the first results from Nano-SIMS (Secondary Ion Mass Spectrometer) analysis on Mediterranean diatoms obtained during the 2016 NESSC cruise.