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四川盆地西南缘乐山—沐川地区的页岩铜银矿床产于上二叠统宣威组上部。地质和常量元素、稀土元素、热释光等地球化学证据表明， 页岩铜银矿床形成于成岩期，成矿流体和成矿物质主要来源于下伏的峨嵋山玄武岩。流体动力学分析表明成矿流体是以单环对流方式进行迁移，流体在玄武岩中迁移并淋滤Ｃｕ 、Ａｇ 金属形成含矿流体，沿西侧基底隆起上升，然后沿宣威组向盆地中心横向迁移，在盆地中部下渗返回玄武岩中形成一个长约１５ ｋｍ 、高约３００ ｍ 的近水平的对流环。进一步的分析与计算表明，该区具有良好的形成中型铜、大型银页岩矿床的地质、构造和流体动力学条件，但难以形成超大型的页岩铜银矿床。
The shale-copper-silver deposit in the Leshan-Muchuan area on the southwestern margin of the Sichuan Basin was produced in the upper part of the Upper Permian Xuanwei Formation. Geochemical evidences such as geologic and macroscopic elements, rare earth elements, and thermoluminescence indicate that the shale copper-silver deposit formed during diagenesis and that the ore-forming fluids and ore-forming materials are mainly derived from the underlying basalt Mount Emei. Hydrodynamic analysis shows that the ore-forming fluid is migrated by single-ring convection. The fluid migrates and leaches Cu in the basalt. Ag metal forms ore-bearing fluid and rises along the base of the west bank. Migrate and infiltrate into the basalt in the middle of the basin to form a nearly horizontal convective ring about 15 km long and about 300 m high. Further analysis and calculation show that the area has good geologic, tectonic and hydrodynamic conditions for forming medium-sized copper and large silver shale deposits, but it is difficult to form super-large shale copper-silver deposits.