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扬子板块西缘晋宁期格宗、东谷花岗岩体具有较高的εＮｄ（ｔ）值（－０．８２～＋２．５４），较低的８７Ｓｒ／８６Ｓｒ初始比值（０．７０３５～０．７０４５），２０６Ｐｂ／２０４Ｐｂ，２０７Ｐｂ／２０４Ｐｂ，２０８Ｐｂ／２０４Ｐｂ分别为１７．４４４～１７．６９５，１５．４０３～１５．５６６，３６．６７１～３７．１８１，δ１８Ｏ值为９．０１‰～１０．１１‰。它们与扬子板块其它边缘（北缘、东缘、东南缘）晋宁期花岗岩的同位素组成特征相类似，都是扬子古大陆板块之古岛孤或古活动大陆边缘非成熟地壳的产物。从扬子板块东缘、西缘、北缘到东南缘，晋宁期花岗岩同位素组成的微小差异显示其物质来源中幔源组分含量依次减少，壳源组分含量依次增加。扬子东南缘西南端的广西摩天岭花岗岩则是古大陆边缘相对较古老成熟地壳的产物。
In the west margin of the Yangtze plate, the Jingzong and Zonggou granite bodies have higher εNd (t) values (-0.82 ~ + 2.54) and lower initial 87Sr / 86Sr ratios (0.7035 ~ 0.7045 ), 206Pb / 204Pb, 207Pb / 204Pb and 208Pb / 204Pb were 17.444-17.695,15.403-15.566,36.671-37.181, respectively, and the δ18O value was 9.01-10.10 ‰. They are similar to the isotopic composition of the Jinning Period granite at the other edges of the Yangtze plate (northern margin, eastern margin and southeastern margin), all of which are the product of the ancient island solitary or ancient palaeoclimate marginal immature crust in the Yangtze ancient continental plate. The slight differences of the isotopic composition of the Jinning Period granitoid from the eastern margin, the western margin, the northern margin to the southeast margin of the Yangtze block show that the source materials of the mantle source components decrease in turn and the contents of crust source components increase in turn. On the southwestern margin of the southeastern margin of the Yangtze River, the Motianling granite in Guangxi Province is the product of relatively ancient and mature crust on the ancient continental margin.