个旧锡矿区两个成岩系列的演化

The Evolution of Two Diagenetic Series of the Gejiu Tin Ore District

根据岩浆岩的物源、岩类、物化特征及成因将个旧地区的火成岩划分为幔源分异系列和壳源重熔系列。幔源分异系列经历了从火山岩到侵入岩演化阶段,火山岩阶段由拉斑玄武岩系经高铝玄武岩系演化到碱性玄武岩系;侵入岩阶段由基性演化到碱性岩浆岩(斑岩)。壳源重熔系列在矿区仅有重熔岩浆阶段,经历了从混染型(斑状)到侵入型(粒状)花岗岩的发展过程。

The magmatites are divided into two diagenetic series in Gejiu area according to magma source, lithofacies, physicochemical characteristics, and genetic connection. They are mantle source differentiation and crust source remelting. Mantle source differentiation series experience an evolution from volcanic rock stage to intrusive rock stage. Volcanic stage means the evolution of tholeiites—high-alumina basalts—alkalibasalts. And intrusive rock stage means the evolution of basic rocks-alkaline rocks—porphyry veins. Crust source remelting series contains only anatectic magma stage. It experience the development processes from contaminated granite (porphyritic) to intrusive one (granular texture).