Ordovician Phosphate-bearing Carbonate Rocks

Sedimentary phosphate deposits are potential sources of rare earth elements (REEs) with the capacity to meet global demand. However, the processes influencing REE incorporation and distribution in these rocks—such as depositional environment, ocean chemistry, and post-depositional alteration—are not fully understood. The Ordovician Lexington Limestone in Kentucky, known for contributing to phosphate-rich soils supporting the state’s equine industry, also contains REEs and uranium, posing radon-related health risks. Dr. Lukoczki’s recently funded project applies crystallographic and geochemical tools to trace phosphate crystallization and recrystallization, uncovering the mechanisms controlling incorporation of trace elements like REEs and uranium in sedimentary phosphates.