Abstract:

Recently, the nontraditional stable isotopic geochemistry has achieved great advancement in the study of the evolution of paleooceanic environment, in which the stable isotopes of redoxsensitive elements (Se,Mo,Fe,etc.) have played an important role. In comparison, the use of stable isotopes of some disperse elements (Ge,Cd,Tl) in tracing the paleooceanic environment was overlooked for years. But these elements have their own special recycling mechanism in the marine system, and thus, the trace of the stable isotopes of these elements may provide potential geological implications for the paleooceanic environment. Their sources and sinks are simple in the marine system; moreover, both inorganic and organic adsorption could control their isotopic fractionations. On the other hand, Ge, Cd and Tl are easily evaporated at high temperature, and their major isotopic fractionation may have occurred during the formation of the primary nebula. There are large scale lowtemperature deposit field in South China, which would provide the best chance to the improvement of Ge,Cd,Tl stable isotopes. In addition, Cd and Tl are the potential toxic elements in the supergene environment; therefore, their isotopic composition could be used to trace the source of contamination.

Key words:

Key words: disperse element; Ge,Cd,Tl stable isotope; isotopic fractionation