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五素火山岩位于哀牢山蛇绿岩带西侧，大地构造位置属于思茅地块。火山岩整合产于早石炭世地层中，厚约８００ｍ，具双峰式特征。野外见４层流纹岩和英安岩，且均与玄武岩呈互层产出。与Ｎ—ＭＯＲＢ比较，五素玄武岩的Ｔｉ含量偏高，Ｔｉ／Ｖ、Ｚｒ／Ｙ比值和ＬＲＥＥ丰度较高，具有Ｅ—ＭＯＲＢ的特征，说明五素玄武岩的原始岩浆可能类似ＯＩＢ的特征，指示其产于板块拉张环境而非岛弧环境。五素玄武岩的Ｔｈ＞Ｔａ，暗示玄武岩经历了陆壳混染作用。综合野外地质和地球化学证据说明，五素双峰式火山岩应当属于大陆溢流玄武岩（ＣＦＢ），产于板块被动陆缘拉张减薄环境。
Wuzuo volcanic rock is located in the west of Ailaoshan ophiolite belt, the earth structure belongs to the Simao block. Volcanic rocks are integrated in the Early Carboniferous strata, about 800 m thick with bimodal characteristics. In the field, there are 4 layers of rhyolite and dacite, both of which are interbedded with basalt. Compared with N-MORB, the pentavalent basalt has high Ti content, high Ti / V, Zr / Y ratio and LREE abundance, and has the characteristics of E-MORB, indicating that the original magma of Wuyuan basalt may be similar to the OIB, Indicate its production in the plate stretch environment rather than the island arc environment. The pentavalent basaltic Th> Ta, suggesting that the basalt experienced continental crusting. Comprehensive geologic and geochemical evidence shows that the five-element bimodal volcanic rocks should belong to the continental overflow basalts (CFB), which are produced in the plateau passive margin stretching and thinning environment.