The lithology of c petrofabric is marble , accidental gneiss . by field attitude , rock association character , petrography and petrochemistry , we know that the protolith of a petrofabric is mainly composed of pelite , sandstone and basic to acidic volcanic , that of b petrofabric mainly a suite of pelite , sandstone ( maybe include volcanic ) , and that of c petrofabric mainly limestone , impurity limestone , a few of pelite and pyroclastic rock A岩组的岩性主要是各种角闪岩类和片麻岩类夹有片岩，偶有变粒岩、大理岩。 b岩组的岩性主要是各种片岩夹有大理岩、石英岩。 c岩组主要是一套大理岩，偶有片麻岩。
