摘要
铷锶等时线法测定地质体年龄是目前普遍应用而准确度较高的方法之一,用该法测得金牙金矿床(JY金矿床)的成矿年龄为206Ma±12,为中三叠世晚期;含金黄铁矿、毒砂矿物包体年龄为276Ma±28,代表成矿物质来源地层的时代,和桂西基性岩时代相同。用铷锶等时线法测得桂西北地区辉绿岩时代为263.1Ma,和峨眉山玄武岩相当,属海西晚期。因此,有根据认为,金牙金矿床的硫砷金等成矿物质主要来自下伏晚二叠世基性岩和基性火山碎屑沉积岩。
It is a popular and relative accurate method for geological body dating to use strontium and rubidium isotime. By this method,the author got the age of ore-forming in Jinya gold mining around 206 Ma ±12, Later Middle Triassic in age , and the age of enclosures in gold - bearing pyrite and dalanite around 276 Ma ±28, which indicates the age of strata of ore-forming materials. It is approximates to that of basic rock in this district. In same way, the age of diabase in this district is around 263. 1 Ma and corresponding to Emeishan Basalt in Sichuan Province, formed in Late Hercynian. It is though that ore-forming materials such as sulfur, arsenic and gold in Jinya gold mining must come from underlying basic rock and basic volcaniclastic rock Late Permian in age.
