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本文阐述了该区出露的超基性岩、基性侵入——喷出岩的区域地质背景、岩石组合及其特征,与世界公认为蛇绿岩套的岩石组合及矿产进行了对比,认为基本相同,但本区规模较小。它既近于洋中脊似拉斑玄武岩,也类似于大陆裂谷的碱性玄武岩,从Na_2O与K_2O的比值来看,认为应该接近后者。本文分析了本区蛇绿岩形成的地壳演化过程,认为铜厂街裂谷属地堑型滇西裂谷系,形成于早石炭世。蛇绿岩属陆间裂谷型。
This paper describes the regional geological background, rock assemblage and its characteristics of ultramafic rocks and basic intrusive-expelling rocks exposed in this area, and compares them with the rock assemblages and minerals recognized as ophiolite sets in the world. Basically the same, but the area is smaller. It is close to mid-ocean ridge like tholeiite basalt and similar to alkaline basalts in continental rift. From the aspect of ratio of Na2O to K2O, it should be close to the latter. This paper analyzes the evolution of the crust formed by ophiolites in this area, and considers that the rift valley of Tongchang Street belongs to the graben-type western Yunnan rift system and formed in the Early Carboniferous. Ophiolite is continental rift type.