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丹巴地区位于川西松潘－甘孜造山带东缘，出露较多的斜长角门岩类．这些岩石通常里透镜状与碳酸盐岩、泥质岩相伴生。地球化学研究表明，这类斜长角闪岩为正斜长角闪岩，原岩主要为钙碱性玄武岩类．岩石富Ｆｅ，Ｍｇ，Ｃａ和Ｔｉ，大离子亲石元素Ｓｒ，Ｂａ，Ｔｈ，Ｎｂ，Ｔａ等比较富集；轻稀土稍富集，铕亏损不明显（δＥｕ＝０．８２～０．９９），稀土总量变化在１１９．４～２０９．９９×１０－６之间．岩石的地球化学特征与拉张构造背景下形成的玄武岩类非常相似．古构造环境研究表明，这类玄武岩形成于晚元古代活动大陆边缘的弧后盆地内，玄武岩浆来自地幔，在上升过程中受到大陆地壳物质混染。
Danba area is located in the eastern margin of the Songpan-Garzê orogenic belt in the western Sichuan Province, exposing more of the longhorn and longhorn door rocks. These rocks are usually lenticular with carbonate and argillaceous rocks. Geochemical studies show that these amphibolite amphibolite is a positive amphibolite, the original rock is mainly calc-alkaline basalt. The rocks are rich in Fe, Mg, Ca and Ti, and large ion lithophile elements such as Sr, Ba, Th, Nb and Ta are relatively enriched. The light rare earth is slightly enriched and the europium depletion is insignificant (δEu = 0.82 ~ 0.99) , The total amount of rare earth changes between 119.4 ~ 209.99 × 10-6. The geochemical characteristics of rocks are very similar to those of basalts formed in the context of extensional tectonics. Paleo-tectonic environment studies have shown that these basalts were formed in the back-arc basin on the margin of the Late Proterozoic continental margin. Basalt magma came from the mantle and was contaminated by the continental crust material during its ascent.