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沿金沙江 墨江缝合带出露了一套年龄为 2 6 5～ 37 6Ma的富碱斑岩 ,大多数斑岩在岩石化学上属碱钙质系列 ,以轻稀土富集和无铕异常为特征 .这些岩石形成在碰撞后的构造环境 ;斑岩、角闪岩捕虏体和玄武岩的 ( 87Sr/86Sr) i 分别是0 70 73,0 70 6 5～ 0 70 71和 0 70 5 8～ 0 70 76 .εNd(T)分别为 - 3 4～ - 6 3,- 2 1～ - 7 4和 - 3 3.这些岩石的Pb同位素也略有差异 .有证据表明 ,斑岩的岩浆源是来自“壳 幔混合层”的部分熔融 .讨论了新生代岩浆活动与板内变形的关系 .
Along the Jinshajiang suture, a set of alkali-rich porphyries aged 26-676 Ma are revealed. Most porphyries are alkaline-calcareous series in petrochemistry and are characterized by light rare earth enrichment and non-Eu anomalies These rocks formed in the post-collision tectonic setting; the (87Sr / 86Sr) i of porphyry, amphibolite xenoliths and basalts were 0 70 73,0 70 6 5 0 70 71 and 0 70 5 8 0 70 76.εNd (T) is -3.4 to -6.3, -2,1 to -7,4 and -3 respectively. The Pb isotopes of these rocks are also slightly different. There is evidence that the porphyry magma originates from Partial melting of “crust-mantle mixed layer” discusses the relationship between Cenozoic magmatic activity and in-plane deformation.