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滇西花岗岩类极为发育,本文根据其物源、成岩机制、成岩环境及岩石系列等因素,将滇西花岗岩划分为准原地再生花岗岩、高侵位重熔花岗岩、断裂变质糜棱花岗岩、中酸性浅成侵入花岗岩及碱性花岗岩五种类型。高侵位重熔花岗岩是锡矿的母岩,成矿作用受花岗岩侵入分异及气热蚀变的控制,在岩体不同部位形成含锡(铌、钽)花岗岩型、锡石伟晶岩型、锡石云英岩型、锡石石英脉型、含锡多金属(磁铁矿)型、锡石硫化物型等不同类型的锡矿床(或矿化)。高硅、富碱及高Rb/Sr比是这类含锡花岗岩的特征标志。滇西东部一些锡矿床(或矿化)与断裂变质糜棱花岗岩密切相关,其物源均来自围岩,经同一断裂变质作用形成,多为锡石硅酸盐矿床,锡石与电气石共生。此外,滇西一些中酸性浅成斑岩中,具有明显的锡矿化,对寻找斑岩锡矿值得注意。
Based on the provenance, diagenesis mechanism, diagenetic environment and series of rocks, the granites in western Yunnan are classified into quasi-situ reclaimed granite, highly emplaced reclaimed granite, fault metamorphic mylonite, Acidic intrusive granite and alkaline granite five types. The high-in-situ grained melted granite is the parent rock of tin ore. The mineralization is controlled by granite intrusion and gas-thermal alteration. In the different parts of the rock mass, tin (niobium and tantalum) Different types of tin deposits (or mineralization) such as cassiterite-type, cassiterite-quartz type, tin-bearing polymetallic (magnetite) type and cassiterite type. High silicon, alkali-rich and high Rb / Sr ratios are hallmarks of this type of tin-bearing granite. Some of the tin deposits (or mineralization) in the eastern part of western Yunnan are closely related to the metamorphic mylonitization granites. The provenances are all from the surrounding rocks and are formed by the same fault metamorphism. They are mostly cassiterite deposits. Symbiosis of cassiterite and tourmaline . In addition, some intermediate-acid epicontinental porphyries in western Yunnan have obvious tin mineralization, which is worth noting in search of porphyry tin deposits.