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扬子地台西缘海相火山岩主要分布在海域裂陷构造、碰撞诱发的裂谷盆地－撞击槽及晋宁－澄江期增生的各类地体中，并以中元古代、二叠－三叠纪最为发育。划分了均一玄武岩组合、玄武岩－安山岩－英安岩－流纹岩组合、玄武岩－流纹岩双峰组合、玄武岩－英安岩－流纹岩－粗面岩组合、细碧角斑岩组合等５种火山岩构造－岩石组合类型。提出以地幔动力部分熔融为主的裂陷－拗拉槽型细碧角斑岩组合和以结晶分异为主岛弧、洋岛、洋脊及部分弧后裂谷型细碧角斑岩组合以及岛弧裂谷（拗拉槽）玄武岩－流纹岩双峰组合是最主要的控制铜多金属矿的构造－火山岩石组合类型。研究表明，碱－偏碱性分异良好的富钠细碧角斑岩系内中酸性火山岩发育的喷发中心相—近火口相、火山喷发旋回末期或喷发间隙期的有利岩石组合是形成中—大型铜多金属矿床的重要条件。
The marine volcanic rocks in the western margin of the Yangtze platform are mainly distributed in marine rift structures, collision-induced rift basins and impingement trenches and various types of terrane accreted in the Jinning-Chengjiang period, and are dominated by Mesoproterozoic-Permian-Triassic Ji most developed. It is divided into two groups: basalt-andesite-dacite-rhyolite assemblage, basaltic-rhyolite bimodal assemblage, basalt-dacite-rhyolite-lithofacies assemblage, Five types of volcanic rock - rock assemblages. It is suggested that the main arc, oceanic island, oceanic ridges and part of postbackback rift-type emeraldite porphyry assemblage, which are dominated by the mantle dynamic melting, As well as the island arc rift (aulacogen) basaltic-rhyolite bimodal assemblages are the most dominant types of tectono-volcanic assemblages that control copper polymetallic deposits. The results show that the favorable lithogenic assemblages of eruption center facies-near-fire facies, late volcanic eruptions or eruption gap periods of alkaline-alkaline breccia fine-grained Meso-acidic volcanic rocks are formed in the mid- Important copper-polymetallic deposits of the important conditions.