Unveiling Foraminiferal Records of Abrupt Climate Change with High-Resolution Synchrotron Imaging

This project aims to determine the mechanisms behind elemental banding in foraminiferal shells, which control the reliability of geochemical proxies. We focus on Globigerinoides ruber, analysing fossil and modern specimens to assess how shell microstructure influences elemental distributions and how patterns are preserved across abrupt climate transitions, including glacial–interglacial shifts (MIS 7→6, 6→5, 5→4, 4→3, 2→1), Heinrich events, Dansgaard–Oeschger cycles, and the Younger Dryas. High-resolution synchrotron nano-CT will characterise the 3D architecture of shell walls—lamellae, pores, and nanogranular domains—while 2D XRF maps of selected fragments will provide spatial distributions of Mg, Ca, Sr, Mn, and Ba. This correlative approach tests hypotheses for band formation and preservation, yielding a mechanistic understanding of biomineralisation, improving proxy interpretation, and enhancing reconstructions of past ocean and climate variability.