乌江干支流河水中U元素的地球化学特征  

Geochemical Characteristics of Dissolved U in the Wujiang River

作　　者：杨曦[1,2,3] 王中良[1,3] 

机构地区：[1]中国科学院地球化学研究所环境地球化学国家重点实验室,贵州贵阳550002 [2]中国科学院研究生院,北京100049 [3]天津师范大学天津市水环境与水资源重点实验室,天津300387

出　　处：《地球与环境》2010年第4期402-408,共7页Earth and Environment

基　　金：中科院知识创新工程重要方向项目(kzcx2-yw-137);国家自然科学基金(40773011;40721002);973计划课题(2010CB434806)资助

摘　　要：本研究对乌江流域河水U浓度进行了测定,系统讨论了乌江流域干支流河水中U的元素地球化学特征,并对其主要来源进行了辨析。研究结果显示,乌江河水中溶解态U的平均浓度约为0.504μg/L,比世界河流平均水平0.186μg/L及长江平均含量0.45μg/L高,但是低于黄河U含量4.86μg/L,同时也低于世界平均海水U浓度3.3μg/L。来源分析显示,乌江河水中的U主要来源于碳酸盐岩风化,尤其是白云岩的风化,对U行为有决定性的控制作用,说明了在海洋沉积成岩过程中生物作用过程对U行为的重要性。蒸发岩和硅酸盐等的风化过程对乌江河水U的贡献不大。和十年前相比,人类活动对流域河水U的影响明显增加。The concentrations of dissolved U were measured in the Wujiang River and its major tributaries. Meanwhile, the geochemical characteristics of dissolved U have been discussed, including the relations between the water chemical characteristics , lithological characters and human activities. The results showed that the average concentration of dissolved U in the Wujiang River is 0.504 μg/L, higher than the global average （0.186 μg/L） and Yangtze average （0.45 μg/L）, but lower than that of the Yellow River （4.86 μg/L）. The concentrations of dissolved U in the Wujiang River Basin are mainly controlled by dissolution of carbonate rocks, especially by dolostones, indicating that the geochemical characteristics of U are effected significantly by biological activities during diagenesis of marine carbonates. Compared with the situation ten years ago, the impact of human activities on U concentrations in the Wujiang River Basin has been obviously enhanced.

关 键 词：乌江流域 铀 风化 碳酸盐岩 

分 类 号：P595[天文地球—地球化学] X143[天文地球—地质学]