The rare earth element compositions of sediments from the loess tableland in the Liyang Plain, southern China: implications for provenance and weathering intensity

Abstract

To identify the weathering intensity and to deduce the provenance of sediments (black-brown soil and loess) from the loess tableland in the Liyang Plain is of great importance for understanding the development and origin of civilization of this critical region in China. The geochemical results show similar REE distribution patterns among sediments sampled from the YC profile in the Liyang Plain, reticulated red soils from the Dongting lake area, Xiashu loess in Zhenjiang, and loess from the Loess Plateau in China. These similarities imply a single provenance, from dust storms. REEs, especially the LREE/ HREE ratio and Eu anomaly, can trace weathering intensity. Higher LREE/HREE ratios, and remarkably Eu anomalies, are present in the top loess (L 0 ), Lower LREE/ HREE ratios and insignificant Eu anomalies are present in black-brown soil (S 0 *) from the Liyang Plain. These demonstrate that the black-brown soils have undergone a lower intensity of weathering than the loess of YC profile. Moreover, CIA values for sediments from the YC profile provide powerful evidence to support the above result. Comparisons of analyses of the REE contents of sediments from the YC profile, of reticulated red soils from the Dongting Lake area, Xiashu loess from the Yangtze River, and loess from the Loess Plateau, clearly show the weathering intensity decreases according to the following sequence: reticulated red soil from the Dongting Lake area [ sediments of YC profile from the Liyang Plain, which formed from dust storms & Xiashu loess from lower reach of the Yangtze River [ loess from the Loess Plateau.

Normalized Rare Earth Elements in Water, Sediments, and Wine: Identifying Sources and Environmental Redox Conditions

“…Taylor et al [59] reported that these deposits, collected from several continents, have REE curves (Figure 7) that closely resemble the shale curve (Figure 2), with slight fractionation between light and heavy REE as a function of grain size [60] and surface weathering [61]. Their bulk composition might, however, be represented by a single grain size, by the <4 µ fraction [62].…”

Health risk assessment of rare earth elements in cereals from mining area in Shandong, China

“…It is estimated that the REE enriched fertilizers released into the cultivated soil were 5,200 tons in 2002 in China 6 . In addition, large-scale exploitation activities of REE resources have resulted in substantial increase of the contamination levels in soil and water around the mining area 7 – 11 . Huang et al .…”

Lithologically-related rare earth element variations the Mio-Pliocene Poznań Formation (Poland)

“…The study shows that the value of eu ro pium anom a lies in the Poznañ clays is higher than in Por tu guese Paleogene and Mio cene clays, in which the Eu/Euchondrite* ra tios range from 0.48 to 0.69, and is also higher than in the loess from the Liyang Plain in south ern China (0.63-0.67) (Mao et al, 2011;Lisboa et al, 2015). The value of eu ro pium anom a lies in Poznañ For mation clays is com pa ra ble or even lower than in sig nif i cantly older Perm ian clays from de pos its in Iran where Eu/Euchondrite* ratios range from 0.79 to 1.34 (Mahjoor et al, 2009).…”