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东川裂谷因民期火山—岩浆活动强烈，也是重要的铁铜成矿期。火山活动旋回均经历爆发—喷发—喷溢—（喷流）阶段。主要发育在裂谷中心落因火山链和蓑衣坡火山盆地中。落因火山链早期形成火山—沉积角砾岩段，火山活动以喷溢的火山熔岩为主，主要有钠质基性熔岩、玄武岩、安山岩，均已蚀变，并有钠长斑岩的侵入活动。中期火山喷发形成凝灰岩类、火山碎屑岩类，发育了铁铜矿化。在蓑衣坡火山盆地中因民期火山—岩浆活动发育两次火山—沉积旋回，即两次爆发（角砾岩）—喷发（凝灰岩）—喷溢（熔岩）—喷流（硅质岩），在喷流相发育赤铁矿层和含铜硅质岩层。
Dongchuan rift due to the national volcano - strong magmatic activity is also an important iron-copper mineralization. Volcanic activity cycles have experienced an explosion - eruption - jet overflow - (jet) stage. Mainly in the center of the rift fell volcanic chain and Yi clothing slope volcanic basin. The volcano-sedimentary breccia section was formed in the early stage of volcanic eruption, and the volcanic activity was dominated by volcanic lava. The main volcanic lava was basic sodium lava, basalt and andesite, which had been altered and invaded by albite activity. The mid-term volcanic eruptions formed tuffs and pyroclastic rocks and developed iron-copper mineralization. Two volcanic-sedimentary cycles developed in the volcanic-magmatic activity of the Yongyi volcano basin during the Manchipu volcanic period, that is, two episodes of outbreaks (breccias), eruptions (tuffs), spurting (lava) and jet flow (chert) Hematite and copper-bearing siliceous rocks develop in the jet stream.