Pb, Nd isotopic study of Proterozoic metamorphic sediments in North Jiangxi and its tectonic significance

Nd, Pb isotopic study of metamorphic sediments of Zhanggongshan Group, Shuangqiaoshan Group, Chenglang Group and Xiushui Group in North Jiangxi shows that the components of Nd and Pb are identical to those of Proterozoic strata from southern margin of the Yangtze block, indicating that they have the same source and tectonic evolution history. The Pb Pb isochron of metamorphic argillite in Shuangqiaoshan Group is 1 490±68 Ma, while the Nd mode ages of Zhanggongshan Group, Shuangqiaoshan Group, Chenglang Group and Xiushui Group are 1.57 Ga, 1.89 Ga, 1.77 Ga, 1.60 Ga,respectively, less than 1.6-1.9 Ga, which suggest that they formed in Middle Proterozoic Subera.