Distribution pattern and geochemical analysis of rare earth elements in deep-ocean sediments

Abstract

The content and distribution pattern of rare earth elements (REEs) in surface sediments from the Eastern and Western Pacific Ocean, the Northern and Southern Atlantic Ocean, and the Southwestern Indian Ocean were explored and the resources and geochemical characteristics of REEs in deep-ocean sediments from different oceans were studied. The total REE abundances (∑REE) in the different oceans ranged as follows:Eastern Pacific, 56.88-500.02 μg/g; Western Pacific, 290.68-439.94 μg/g; Northern Atlantic, 55.33-154.90 μg/g; Southern Atlantic, 40.83-69.30 μg/g; and Southwestern Indian Ocean, 20.24-64.76 μg/g. Their corresponding LREE (La-Eu)/HREE (Gd-Lu) average values were 5.18, 5.86, 9.01, 5.21, and 4.59, which indicated that the light REEs were all evidently enriched. δEu and δCe showed slight Eu-negative anomalies and significant Ce-positive anomalies in all sediments. Although the contents of REEs in the sediments varied among the different oceans, the distribution patterns of REEs were similar, and the correlation coefficient was greater than 0.929 0. In the Eastern Pacific sediments, ΣREE showed a significantly positive correlation with Co, Cu, Zn, Mn, Mo and a weak correlation with Fe. In the Western Pacific and Southern Atlantic sediments, ΣREE presented no obvious correlation and a weakly negative correlation with Co, Cu, Zn, Mn, Mo and Fe, respectively. ΣREE in the Southwestern Indian Ocean sediments positively correlated with Cu, Zn, Mn, Mo, Fe, and had a weakly negative correlation with Co.