Authigenic phosphate minerals are widely recognized as the primary hosts of rare earth elements (REEs) in pelagic sediments, yet the contribution of biogenic particles to transferring scavenged REEs into surficial sediments remains poorly constrained. Here we combine the GEOTRACES suspended-particle dataset with spatially paired surficial sediment data to investigate this process from a particle-sediment continuum perspective. Sediments from the eastern South Pacific and central North Pacific show substantially higher Nd/Al and Nd/Mn ratios than their corresponding deep-water particles. The excess Nd enrichment clusters in regions of elevated particulate organic carbon export. Combined Eu anomaly and Nd isotope evidence rules out hydrothermal inputs as the additional Nd source required to explain this enrichment. Together, these observations suggest that biogenic particle export amplifies Nd burial by transporting seawater-derived Nd to the seafloor and releasing it during particle remineralization within sediments. Enhanced biogenic export simultaneously supplies phosphorus for authigenic phosphate formation, thereby promoting long-term REE sequestration in sediments.

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