(a) Simplified structural map of the western High Atlas in Morocco, modified from El Bamiki et al. (2020). (b) Detailed lithostratigraphic column of the Erguita section with interpreted regressive and transgressive trends. (c) Gamma-ray curve showing the U content within the sediments. It is assumed that U reflects the proportion of phosphate minerals because of their great incorporation of trace elements, including U, compared to carbonates, sandstones, and marls (Aubineau et al., 2022a; Nathan, 1984).