심해퇴적물 내 희토류원소의 분포와 연구 현황 = Distribution of rare earth elements and Yttrium in deep-sea sediments and current research status

다국어 초록 (Multilingual Abstract)

Rare earth elements and yttrium (REY) are critical resources for advanced industries and have recently attracted attention as alternative sources due to their high concentrations in Pacific deep-sea sediments. This review summarizes recent studies on the spatial distribution, host minerals, enrichment mechanisms and depositional timing of REY in major oceanic regions, with a particular focus on the Pacific, in order to improve the geochemical understanding of their occurrence and behavior. In deep-sea sediments, REY is often highly concentrated within specific stratigraphic horizons, indicating episodic enrichment events associated with specific geological time periods.
Biogenic apatite has been identified as the primary host phase, with Fe-Mn oxides acting as secondary sources or carriers. REY enrichment is considered to be strongly associated with paleoceanographic conditions such as enhanced bottom currents. However, interpretation of the chronology and spatial distribution of REY-rich layers remains challenging due to low sedimentation rates and complex seafloor bathymetry.
This review highlights these limitations in current understanding and emphasizes the need for multi-proxy age models and integrated multi-core geochemical analyses to better understand the paleoceanographic significance of REY enrichment events and to enhance future deep seabed resources exploration.