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赣北地区元古代变质沉积岩的铅、钕同位素研究结果表明,它们与扬子古陆南缘其他元古代地层非常相似,表明它们具有相似的成岩物质来源及构造演化历史。研究结果还显示,双桥山群变质泥质岩的PbPb等时线年龄为(1490±68)Ma,而障公山群、双桥山群、程浪群和修水群的钕模式年龄分别为1.57Ga、1.89Ga、1.77Ga和1.60Ga,均分布在1.5～1.9Ga之间,表明这些地层的形成年龄应小于1.9Ga,是中—晚元古代的产物,同时表明扬子古陆南缘存在古元古代的基底。
The results of Pb and Nd isotope studies of the Proterozoic metamorphic sedimentary rocks in northern Jiangxi show that they are very similar to other Proterozoic strata on the southern margin of Yangtze Palaeogeography and indicate that they have similar diagenetic source and tectonic evolution history. The results also show that the PbPb isochron age of the metamorphic mudstone in Shuangqiao Group is (1490 ± 68) Ma, while that of the Baoguanshan Group, Shuangqiao Group, Chenglang Group and Xiu-Shui Group are 1.57 Ga, 1.89Ga, 1.77Ga and 1.60Ga, all distributed between 1.5 and 1.9Ga, indicating that the formation age of these strata should be less than 1.9Ga, which is the product of the Meso-Late Proterozoic. Meanwhile, the paleo-Proterozoic Of the substrate.