Distribution characteristics and influencing factors of rare earth elements in surface sediments in the southern nearshore waters of the North Yellow Sea

The surface sediments of 52 stations in the coastal waters of the southern part of the North Yellow Sea and the sediments of 7 main inflowing rivers were sampled, and the sample particle size and rare earth elements (REE) were tested. Based on this, the particle size and REE content in the study area were analyzed. Planar distribution characteristics of REE content, and the influencing factors of REE distribution were discussed. Results show that the surface sediments in the study area generally exhibit the characteristics of finer grain size from nearshore to seaward. The content of REEs in the study area is generally higher than those in the Changjiang (Yangtze) River, Huanghe (Yellow) River, and Chinese loess areas, and is generally characterized by the enrichment of light REE and depletion of heavy REEs. The content and distribution characteristics of REEs are affected by various factors such as grain size characteristics, mineral composition, weathering and material sources. Among them, mineral composition has a more significant impact on REEs in the study area. The high content of REE may be related to the enrichment of land-sourced detrital minerals (feldspar minerals, titanium-containing minerals, etc.). Particle size characteristics and weathering have a certain effect on the distribution of REEs in the fine-grained sediments. The effect of weathering on rare earth elements is mainly accomplished through the mixing of multiple sources.The material sources indicated by REEs in the study area are mainly sediments from the Huanghe River.