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马厂箐钼铜金矿床是金沙江-哀牢山断裂带上与喜马拉雅期富碱斑岩有关的典型矿床之一,其成矿作用具有特殊性。本文应用透岩浆流体成矿理论,重点探讨了马厂箐钼铜金矿床深部地质过程中成岩与由地幔流体作用引发壳幔混染并形成系列成矿的关系。通过对马厂箐矿床成岩成矿时代的厘定、岩矿石稀土和微量元素、稀有气体及Pb-Sr-Nd同位素研究,论证了成矿流体和岩浆流体均来自于富集地幔,这种成矿流体是包含于富碱岩浆并与其互不混溶的地幔流体。在上升运移过程中,地幔流体可随富碱岩浆的结晶成岩过程对岩体进行同步自交代蚀变而在斑岩体内或其深部形成矿床;也可与岩浆分离而独立运移,在岩体与围岩的接触带及地层围岩中进行交代蚀变成矿。在这一成岩成矿过程中,引发并促进壳幔物质混染和叠加成矿,由此导致了马厂箐矿区成矿分带表现为从岩体到围岩、从高温到低温的不同矿种和不同类型的系列成矿效应。
The Machangba molybdenum copper-gold deposit is one of the typical deposits related to Himalayan alkali-rich porphyries in the Jinshajiang-Ailaoshan fracture belt, and its metallogenesis is special. In this paper, we use the theory of metallogenic fluidization through magmatic fluids and focus on the relationship between diagenesis in the deep geologic process of Ma-Cu-Mo molybdenum-copper-gold deposit and the mantle-fluid mixing and formation of a series of metallogenic processes. Based on the determination of diagenesis and mineralization age, rare earth elements and trace elements, rare gas and Pb-Sr-Nd isotopes in the Machangwan deposit, it is demonstrated that the ore-forming fluids and magma fluids are all from the enrichment mantle. The fluid is a mantle fluid that is contained in alkali-rich magma and immiscible with it. During the process of uplift and migration, the mantle fluid can form self-alteration and alteration along with the crystallization of alkali-rich magma during the process of crystallization and diagenesis, forming ore deposits in the porphyry or in the deep part of the porphyry. It can also separate and separate from the magma, The contact zone between the rock mass and the surrounding rock and the surrounding rock of the strata carry out alteration alteration and mineralization. In this process of diagenesis and mineralization, the crust-mantle material contamination and superimposition mineralization are initiated and promoted, resulting in the ore-forming zoning of the Mazhangwan mining area from rock mass to surrounding rock and from high temperature to low temperature A series of different types of metallogenic effects.