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研究区内有两类密切共生的活动陆缘型幔源侵入岩组合，它们分属拉斑系列和钙碱系列。这两个系列的侵入岩存在系统的化学差异，而且在高位岩浆房中普遍经历了镁铁矿物的分离结晶作用。拉斑系列与钙碱系列均具有板块会聚边缘幔源岩浆的地球化学特征。它们均不同程度地富集大离子亲石元素而贫高场强元素、过渡族元素和重稀土元素。地球化学研究证明，这两个系列的岩浆起源于同一贫化型地幔源区，源岩类型为尖晶石橄榄岩。大离子亲石元素的富集应归因于消减板块的脱水作用或熔融作用。两个系列间的化学差异起因于拉斑系列的熔融程度高于钙碱系列。它们均为晋宁期古秦岭洋盆闭合过程的产物
There are two types of closely-intergrated active margin mantle-derived intrusive rock assemblages in the study area, which belong to the plaque series and the calcium-alkali series. There are systematic chemical differences between these two series of intrusive rocks, and they generally undergo the separation and crystallization of mafic minerals in the high magmatic chambers. Plaque series and calcareous series all have geochemical characteristics of mantle-derived magma at plate convergence margin. They are enriched to varying degrees, large ion lithophile elements and poor high field strength elements, transitional elements and heavy rare earth elements. Geochemical studies have shown that these two series of magma originated from the same depleted mantle source and the source rock type is spinel peridotite. The enrichment of large ion lithophile elements should be attributed to the dehydration or melting of the abatement plate. The chemical differences between the two series are due to the higher degree of melting of the plaque series than the caustic soda series. They are the product of the closed Qinling ancient Qinling basin