Dating rare earth element enrichment in deep-sea sediments using U-Pb geochronology of bioapatite

Abstract Deep-sea sediments rich in rare earth elements and yttrium (REY) are promising mineral resources that believed to be associated with the burial of fish debris. However, nature REY enrichment is poorly understood, part due a lack robust age constraints. We report bioapatite U-Pb ages from an Ocean Drilling Program (Leg 199, Hole 1218A) core REY-rich sedimentary Pacific Ocean, which yielded ranging 22.8 18.2 Ma 6.5 2.2 Ma, respectively. The teeth 1218A consistent biostratigraphic constraints, shed light on application chronometer, yield absolute time scale for stratigraphy, especially sequences deposited below calcite compensation depth (CCD), where there absence fossil carbonate. successful measurement REY-enriched sediment suggests mineralization occurred no later than Miocene western Ocean. Uranium positively correlated REY, suggesting U were incorporated into lattice simultaneously, making chronometer suitable constraining timing mineralization. When combined published data, our study accumulation event was influenced by high P2O5 MnO2 contents oxic bottom water.