Fig. 9: Geochemical provenance variability in correlative greenish grey interglacial beds with IRD at Sites U1532 and U1533.

Grey shading designates a 97.5 % confidence envelope of a LOWESS regression model fitted through the data. a La/Th values are highly variable in ice-rafted debris (IRD)-bearing interglacial beds deposited between 5.1 and 4.5 Ma, and relatively constant and low in IRD-bearing interglacial beds deposited between ~4.5 and 3.9 Ma. Higher La/Th values indicate an arc-volcanic source in the Cretaceous-Cenozoic central and western domain of West Antarctica and/or a larger pelagic component, whereas lower La/Th ratios coincide with intervals with a larger terrigenous component and a source within the Triassic and older terrains of the eastern domain (Fig. 1 and Supplementary Fig. 1). b Sand wt.% ( >63 µm) in samples from the greenish grey facies are high between ~4.6 and 4.5 Ma. c Linear sedimentation rates (LSR in m/Myr) are high around ~5 Ma and between ~4.6 and 4.5 Ma. The age model and LSR are based on paleomagnetic age tie points and correlations of greenish grey facies to the ages of glacial terminations in the LR04 benthic stack^69,95. Source data are provided as a Source Data file.