Figure 4: Integrated redox interpretations compared with local ecology.

A comprehensive redox interpretation is shown for each of the nine localities in the Nama Group, determined using combined Fe and Ce signals. In situ fossils (grey lines), and local ecologies⁵ and general ecology from the literature^17,18 are shown alongside local water column redox conditions (b). The bar chart plots the frequency that different biota are found in each redox zone⁵ (a). Large skeletal fossils and burrows are found exclusively in well-oxygenated settings and small skeletal fossils are largely restricted to well-oxygenated conditions, but may occur where conditions were only fleetingly oxic.