Phys.org September 24, 2024
Iron oxide-apatite (IOA) deposits have substantial rare earth elements potential, but their rare earth element (REE) enrichment mechanisms remain uncertain. An international team of researchers (Australia, China) used novel layered piston-cylinder experiments to address these questions. Seventeen magmatic FeP–Si immiscibility experiments, across 800–1150 °C, and at 0.4 and 0.8 GPa, reproduced many natural textural and geochemical features of IOA deposits. Magmatic-hydrothermal fluid bubbles and iron oxide-bubble pairs also formed. The results strongly supported FeP–Si immiscibility as a controlling factor in IOA deposits, although not mutually exclusive with other models. Light REE partition into FeP liquids, preferentially to heavy REE, explaining the light REE enrichment of IOA deposits. Some values reach above 100, much higher than previously reported… read more. Open Access TECHNICAL ARTICLE
