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在滇西昌宁—孟连带中,泥盆纪到三叠纪地层呈南北向条带分布。根据岩性在横向分布和纵向上的变化情况,可将泥盆纪到三叠纪的地层序列大致划分成4种类型:①碎屑岩向上在中部夹灰岩透镜体,并在上部变成细粒碎屑岩和硅质岩交互出现;②碎屑岩向上夹灰岩透镜体和少量硅质岩,顶部为二叠纪基性火山岩;③碎屑岩—基性火山岩和火山碎屑岩及碎屑岩夹层—碳酸岩—碎屑岩;④灰岩、白云质灰岩—灰黑色薄层灰岩、泥质灰岩、泥岩夹硅质泥岩。
In the Changning-Menglian belt in western Yunnan, the Devonian-Triassic strata are distributed in the north-south direction. According to the horizontal and vertical changes of lithology, the Devonian-Triassic stratigraphic sequences can be broadly divided into four types: (1) clastic rocks are sandwiched upward in the middle of the limestone body and become Fine-grained clastic rocks interact with chert; (2) clastic rocks uplifted limestone lenses and a small amount of cherts, with Permian basic volcanic rocks on the top; clastic rocks-basic volcanic rocks and pyroclastic rocks And clastic interlayer - carbonate rocks - clastic rocks; ④ limestone, dolomitic limestone - gray-black thin layer of limestone, argillite, mudstone with siliceous mudstone.