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在滇西单拉铜矿区发现了４层硅质岩，该硅质岩具有低的ＴｉＯ２，Ａｌ２Ｏ３与高的成矿元素（Ｃｕ，Ａｕ，Ａｇ）含量特征．硅质岩稀土元素总量很低，其球粒陨石标准化配分模 式为向右倾的曲线，具有明显的负Ｅｕ异常与弱的正Ｃｅ异常，与矿区早期形成的块状硫 化物矿石、矿石矿物及脉石矿物具有一致的稀土元素球粒陨石标准化配分模式，而与 成矿中晚期形成的夕卡岩型矿石及破碎带充填交代型矿石明显不同．硅质岩的硅同位 素组成与热水沉积的硅华及硅质岩一致，它的铅同位素组成与块状硫化物矿石一致， 它的 Ｒｂ－Ｓｒ等时线年龄为 ２７２ Ｍａ± ６ Ｍａ，与赋矿地层时代一致．研究表明羊拉矿区硅 质岩为典型的热水沉积硅质岩，且与矿区块状硫化物矿体关系密切，这为该矿床块状 硫化物矿体为海底喷流热水沉积作用形成提供了直接的证据．
Four layers of chert are found in the Shanla copper deposit in western Yunnan. The chert is characterized by low contents of TiO2, Al2O3 and high metallogenic elements (Cu, Au, Ag). The total amount of rare earth elements in chert is very low. The normalized distribution pattern of chondrites has a right-leaning curve with obvious negative Eu anomaly and weak positive Ce anomaly, which is in close relationship with the massive sulphide ores, ore minerals and The gangue minerals have the same uniform distribution pattern of rare earth chondrules, which is obviously different from the skarn-type ores formed in the middle and late stages of mineralization and the filling of metasomatic rocks with broken belts. The silicon isotope composition of the chert is consistent with the hydrothermal sedimentary silicic and chert, and its lead isotopic composition is consistent with that of the massive sulphide ore. Its Rb-Sr isochron age is 272 Ma ± 6 Ma, The age of ore deposit is consistent. The results show that the cherts in Yangla mining area are typical hydrothermal sedimentary cherts and are closely related to massive sulphide ore bodies in the ore area, providing the massive sulphide orebodies for the formation of hydrothermal sediments in submarine jets The direct evidence.