The geochemical evolution of the proterozoic continental crust in northwestern Jiangxi and western Zhejiang, China

Abstract

The petrochemistry and Sm-Nd isotopic compositions and- the geochemical characteristics of REE, U,Th, etc. in the Late Proterozoic and Early Palaeozoic strata in northwestern Jiangxi and western Zhejiang provinces are described in this paper. It seems to be sure that the middle Proterozoic strata of southeastern China are low in the degree of maturation. The strata contain much mantle-derived material. At the end of Late Proterozoic there was an abrupt turn with respect to the crustal geochemical evolution of the eastern part of South China. Since then, the geochemical environment has undergone a change from a simple reducing environment to a complex oxidizing-reducing environment, which would be geochemically beneficial to the formation of Late Sinian to Early Cambrian U-bearing formations.