Seasonal and spatial variations of rare earth elements in rainwaters, river waters and total suspended particles in air in South Korea

The concentrations and fractionation of 14 rare earth elements (REEs) such as La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu in filtered water, suspended particles and surface sediments at 10 sampling sites from Gansu, Ningxia and Inner Mongolia sections of the Yellow River of China were studied by HR-ICP-MS. The results demonstrated that the total concentrations of REEs (REEs) in filtered water varied from 0.017 to 0.079 μg/L and had high concentration at S3 (0.079), S1 (0.070) and S4 (0.063) in Inner Mongolia section, while in suspended particles and surface sediments, the ranges were 148.9-246.8 mg/kg (mean 176.4) and 109.9-252.0 mg/kg (mean 179.9), respectively, and showed high concentration at S9 (246.8), S7 (252.0), S8 (229.8) in Baiyin (Gansu section) and S1 (209.5) in Baotou (Inner Mongolia section). The ratios of L/H, δEu and δCe in suspended particles and surface sediments implied light-REEs enrichment in the water compared with the background value of Chinese soil. And the chondrite-normalized REEs patterns of the suspended particles and surface sediments also showed light REEs enrichment at S1, S7, S8 and S9. The high concentrations of REEs in the Yellow River were probably due to the weathering of soil and anthropogenic activities near the river.

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New insights about the rare earth elements (REE) mobility in river waters

BSGF - Earth Sciences Bulletin ◽

10.2113/173.2.147 ◽

2002 ◽

Vol 173 (2) ◽

pp. 147-160 ◽

Cited By ~ 20

Author(s):

Samuel Deberdt ◽

Jérôme Viers ◽

Bernard Dupré

Keyword(s):

Rare Earth ◽

Rare Earth Elements ◽

River Waters ◽

Geological Processes ◽

Ree Distribution ◽

Colloidal Matter ◽

Ree Mobility ◽

First Time ◽

Colloidal Fraction ◽

The Rare Earth

Abstract While the rare earth elements (REE) have largely contributed to the understanding of some internal geological processes, their use as tracers of superficial mechanisms (i.e., weathering and elements transport) remains tricky. This results from the poor knowledge we have of the REE distribution in the different fractions of solutions. Up to recently, the studies carried out on the REE behavior in continental aquatic systems were mainly based on the “paniculate” and “solution” fractions separated by an arbitrary filtration through a 0.20 or 0.45 μm pore size membrane. Some recent work has shown, using ultrafiltration experiments, that REE are mainly contained in the colloidal fraction (i.e., 0.20 μm - 1 nm). However, studies devoted to the control of REE by the colloidal matter, have essentially focused on the organic pool (i.e., humic substances). By contrast, the mineral colloidal pool has received little attention. In order to model these processes, we have developed a combined approach that consider (1) ultrafiltration experiments performed on a series of rivers located in Africa (Cameroon) and south America (Brazil, Venezuela) and (2) speciation calculations. This quantitative approach reveals, for the first time, that more than 60 % of the total REE in the solution of river waters is controlled by the mineral colloidal pool.

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