[Enrichment and release of uranium during weathering of sedimentary rocks in Wujiang catchments].
Thirteen weathering profiles of typical rocks such as limestone, dolomitic limestone, dolomite, sillcalite, black shale and purple sandrock from Wujiang catchments were selected for discussing enrichment and release behavior of uranium (U) during rock weathering, and studying its impact on riverine U distribution in the catchments during weathering of these rocks with methods of correlation analysis and mass balance calculation. The purpose of this study is to improve our understanding on biogechemical cycling of U and set a basis for catchment protection against U pollution. The results show that the enrichment extent of U in soils from the Wujiang catchments is usually higher than that of upper continental crust (UCC), China soil (CS) and world soil (WS). The ability of enrichment and release of U is partly controlled by content of U in bedrocks, contents and adsorption ability of clay minerals and Fe-oxides/hydroxides in weathering profiles. Our study also reveals that release of U mainly from weathering of limestone and partly from weathering of dolomite and clastic rocks exerts an important control on riverine U distribution.
Song
Zhao-Liang
ZL
State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China. songzl78@163.com
Liu
Cong-Qiang
CQ
Han
Gui-Lin
GL
Wang
Zhong-Liang
ZL
Yang
Cheng
C
Liu
Zhan-Min
ZM
D002681:China; D004787:Environmental Pollution / Q000032:analysis / Q000517:prevention & control; D005618:Fresh Water / Q000032:analysis; D005843:Geography; D019015:Geologic Sediments / Q000737:chemistry*; D045483:Rivers; D012990:Soil Pollutants, Radioactive / Q000032:analysis*; D014501:Uranium / Q000032:analysis*; D014875:Water Pollutants, Radioactive / Q000032:analysis*
D012990:Soil Pollutants, Radioactive; D014875:Water Pollutants, Radioactive; D014501:Uranium