Pioneer research of this project’s supervisory team (Emsbo et al. 2015, 2016) demonstrated the unrealized potential of phosphorites from the Upper Ordovician Maquoketa Group (central USA) as stratabound Rare Earth Element (REE) ores, dwarfing the economic potential of the deposits that are currently mined for these resources. In addition, the REEs can be beneficiated in a much more environmentally friendly manner. However, our understanding of the extent, formation and potential exploration of the Maquoketa Group is critically hamstrung by significant uncertainties about its geology. This project will solve standing questions on this unit’s precise stratigraphical position and architecture, in order to understand its formation, context & age, and to accurately map the full extent & volume of its REEphosphateresources. Rooted in this case study, ultimately, our research will help track and target similar REEphosphatedeposits across the globe.