勉县－略阳结合带变质火山岩以基性和中基性岩石为主体，见有少量英安质火山岩。可区分为两种岩石－构造组合类型：一类为低钾高钛、轻稀土亏损的拉斑玄武岩，Ｔｉ／Ｖ、Ｔｈ／Ｔａ、Ｔｈ／Ｙｂ、Ｔａ／Ｙｂ表明其应属于ＭＯＲＢ型玄武岩；另一类为岛弧火山岩组合，以钙碱性安山岩类为主体，并有少量岛弧拉斑玄武岩类。 The Mianxian-Lueyang combination zone metamorphic volcanic rocks are mainly composed of basic and medium-basic rocks, with a few of the amphibolite-bearing volcanic rocks. There are two types of rock-tectonic assemblages: Ti / V, Th / Ta, Th / Yb and Ta / Yb, which are low-K, The other is the arc-arc volcanic assemblage, mainly composed of calc-alkaline andesite and a small amount of island arc tholeiite basalts.