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北大别杂岩主要由花岗质片麻岩及斜长角闪岩组成 ,含有不同类型、大小不等的麻粒岩岩块和变质超镁铁质岩块 ,侵入有大量白垩纪花岗岩和辉石 -辉长岩类。其中的花岗质片麻岩、斜长角闪岩具有岛弧环境的岩石地球化学特征 ,代表拼贴于扬子陆块北缘的新元古代古岛弧。北大别杂岩北可与庐镇关群相连 ,南俯于超高压变质岩之下 ,在三叠纪扬子陆块与华北陆块的碰撞过程中 ,曾与超高压变质岩一起俯冲到地幔深度并经受榴辉岩相变质作用 ,然后在折返过程中叠加了麻粒岩相及角闪岩相变质作用 ,是扬子陆块北缘陆壳俯冲基底的一部分
The North Dabie complex is mainly composed of granitic gneiss and amphibolite, which contains different types and sizes of granulite and metamorphic ultramafic rocks, intrusion of a large number of Cretaceous granite and Hui Stone - gabbro class. The granitic gneiss and amphibolite have the geochemical characteristics of the island arc environment and represent the Neoproterozoic ancient island arc collapsed in the northern margin of the Yangtze block. The North Dabie complex can be connected with the Guanqun group in Lu Town and the South under the UHP metamorphic rocks. During the collision between the Triassic Yangtze block and the North China continent, the North Dabie complex had been subducted with the UHP metamorphic rocks to the depth of the mantle And undergo eclogite facies metamorphism, and then superimposed granulite facies and amphibolite facies metamorphism during the reentry process, which is a part of the continental crust subduction basement in the northern margin of the Yangtze block