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Identifying the degree of luminescence signal bleaching in fluvial sediments from the Inner Mongolian reaches of the Yellow River

Li F., Pan B., Lai Z., Gao H., Ou X.

Geochronometria

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2018

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Vol. 45, no. 1

82--96

EN

The partial bleaching of the luminescence signal prior to deposition results in age overestimation, and can be a problem in delineating fluvial evolution within an OSL chronological framework. The Inner Mongolian reaches of the Yellow River are characterised by a high sediment load and complex sources of sediments. To test the incomplete bleaching occurring in this type of environment, the residual doses and the luminescence signal characteristics of different particle size fractions from 14 modern fluvial sediment samples were investigated. Furthermore, 26 OSL ages derived from drilling cores were compared with 11 radiocarbon ages. Our results show that the residual equivalent doses principally range between 0.16 and 0.49 Gy for silt grains, and between 0.35 and 3.72 Gy for sand grains of modern samples. This suggests that medium-grained quartz has been well bleached prior to deposition, and is preferable to coarse-grained quartz when dating fluvial sediments in this region. The results also show that the De values of coarse-grained fractions display a stronger correlation with distance downstream. In addition, a comparison of OSL and radiocarbon ages from drilling cores establishes further confidence that any initial bleaching of these sediments was sufficient. As a result, we believe that the studied fluvial samples were well bleached prior to deposition.

2

Speciation and contamination assessment of metals in the sediments from the Lanzhou section of the Yellow River, China

Jun R., Zhen S., Ling T., Jianxiu H.

Environment Protection Engineering

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2017

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Vol. 43, nr 3

113--124

EN

Heavy metals such as Cu, Fe, Mn, Ni, Zn, Cd, Cr and Pb in surface sediments from the Lanzhou Section of the Yellow River were investigated to analyze chemical speciation by a sequential "extraction and to evaluate their pollution level. The metal contents in the sediments were found to be in the range of (mg/kg) Cu 15.52-57.50, Fe 19 600.33-48 350.00, Mn 493.50-698.93, Ni 9.34-53.20, Zn 64.86-168.57, Cd 1.09-4.25, Cr 70.00-139.33, Pb 5.66-19.13. The arrangement of metal contents from higher to lower was: Fe > Mn > Cr > Zn > Ni > Cu > Pb > Cd. Fe, Mn and Cu and could have the same source according to their correlations. The quantity of immobile speciation (residual) was observed to be higher when compared with mobile speciation (acid soluble, reducible, and oxidizable) of Fe, Cu, Cd and Cr. The highly enrichment factors of Ni and Cr created a high environmental risk. The order of contamination level for heavy metals in sediment was Cr > Cd > Pb > Cu > Mn > Ni > Fe > Zn on the basis of performance of the geoaccumulation index, enrichment factor and pollution load index.

3

Gospodarownie wodą w dorzeczu Rzeki Żółtej

Sobkowiak L.

Gospodarka Wodna

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2012

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Nr 12

505--510

PL

W pierwszej części artykułu omówiono rozwój regulacji rzecznych w dorzeczu Rzeki Żółtej od starożytności do drugiej połowy XX w., a w drugiej zarysowano problemy gospodarowania wodą, jakie pojawiły się na omaiwanym obszarze w ciagu ostatnich 60 lat.

EN

The first section of the article is devoted to the Yellow River basin regulation development from the Antiquity to the second half of the 20th century; the second part describes water management issues that have appeared in the discussed region during the last 60 years.

4

Tunel do transportu Wody z Żółtej Rzeki

Dobosz D.

Geoinżynieria : drogi, mosty, tunele

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2011

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nr 3

98-98