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东秦岭松树沟蛇绿岩是秦岭造山带中出露于变质基底岩系之上的、形成于中元古代晚期（１０００～１２５０Ｍａ）的异地蛇绿岩构造岩片，与周围变质地层里构造接触关系，为一自南而北的逆冲推覆岩片，于９８３Ｍａ±发生构造侵位及变质作用。蛇绿岩主要由超镁铁岩和镁铁岩两个单元组成，变质橄榄岩（纯橄榄岩、方辉橄榄岩）具地幔残余成因，ΣＲＥＥ低，ＲＥＥ特征为ＬＲＥＥ富集、ＨＲＥＥ近平坦型式。变质基性火山岩的常量元素、微量元素和稀土元素地球化学特征显示以Ｔ－ＭＯＲＢ为主，兼具有ＯＩＢ特征，形成于小洋盆构造环境，于晋宁期北秦岭活动大陆边缘的俯冲－碰撞过程中发生变形变质并侵位于陆壳当中。
The East Qinling Songshugou ophiolite was exposed in the metamorphic basement rocks in the Qinling orogenic belt and formed in the remote metaphase ophiolite tectonism in the late Mesoproterozoic (1000 ~ 1250Ma) with structural contact with the surrounding metamorphic strata , A thrusting nappe from south to north, tectonic emplacement and metamorphism occurred at 983Ma ±. The ophiolite is mainly composed of two units of ultramafite and mafic rocks. The metamorphic peridotites (dunite and harzburgite) have mantle remnant origin, low ΣREE, REE characterized by LREE enrichment and HREE sub-flat type . The geochemical characteristics of major, trace elements and rare earth elements in the metamorphic basement volcanics show that they are mainly T-MORB and have OIB characteristics. They are formed in a small oceanic basin environment and are subducted and collided on the active continental margin of Qinling North Qinling Period Deformation occurred during the metamorphosis and invasion in the continental crust.