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大别山北部变质镁铁- 超镁铁质岩带中的中酸性片麻岩主要可分为三类:①英云闪长质片麻岩、②花岗闪长质片麻岩和③二长花岗质片麻岩,其原岩属于一套钙碱性的中酸性花岗岩系列。岩石地球化学特征表明,它们分别形成于板块碰撞前消减地区( 消减的活动板块边缘) 、板块碰撞后隆起花岗石区和同碰撞花岗岩区。其中,形成于800 ~1000 Ma 左右的英云闪长质片麻岩经受过麻粒岩相变质作用并与该带中属于蛇绿岩成员的变基性熔岩有亲缘关系, 可能属于蛇绿岩中的浅色组分。
The intermediate-acid gneisses from the metamorphic mafic-ultramafic belt in the northern part of the Dabie Mountains can be divided into three main types: ① dioritic dioritic gneiss, ② granodiorite gneiss and ③ two long flowers Gangitic gneiss, the original rock belongs to a series of calcium-alkaline granite series. Petrological and geochemical characteristics indicate that they were formed in the area of abatement before slab collision (abatement of the active plate margin). After plate collision, the granite area and the collisional granite area were uplifted. Among them, the Ying-dioritic gneisses formed at about 800-1000 Ma have undergone granulite-facies metamorphism and are related to the metamorphic lavas that belong to the ophiolite in the belt and may belong to the ophiolite In the light-colored components.