Fractionation of Rare Earth Elements in Aquatic Geochemical Processes

。将进行实验室实验，以确定三价稀土在水和沉积物中的地球化学相互作用过程中是否以及如何进行分馏。现场数据表明，分馏发生在风化和土壤发育过程中，发生在氧化还原活性海洋沉积物的早期成岩作用期间，发生在具有氧化/缺氧边界的海相和河口盆地的水柱中。人们对控制三价稀土分馏的反应和化学因素知之甚少。而分馏作用又是稀土元素系列的独特特征，是了解这些重要元素的地球化学循环的基础。重点将放在开发自然浓度的溶液和固相的自然过程的实验室模拟上。稀土元素的放射性同位素将被用作不同反应的示踪剂。

. J H.Laboratory experiments will be performed to determine if and how trivalent REE are fractionated during their geochemical interactions in waters and sediments. Field data have shown that fractionation occurs during weathering and soil development, during early diagenesis of redox.reactive marine sediments and in the water column of marine and estuarine basins with oxic/anoxic boundaries. Little is known about the reactions and chemical factors which govern fractionation of trivalent REE. Fractionation, in turn, is a unique characteristic of REE series and forms the basis for understanding geochemical cycling of these important elements. Emphasis will be placed on developing laboratory simulation of natural processes at natural concentrations of solution and solid phases. Radioactive isotopes of REE will be used as tracers for the different reactions.