川西北微细浸染型金矿床石英脉及其特征  

QUARTZ VEINS AND THEIR FEATURES OF MICRO-GRAIN TYPE DISSEMINATED GOLD DEPOSITS IN NORTH-WESTERN SICHUAN PROVINCE

作　　者：王可勇[1] 姚书振[2] 张保民[2] 张晓军[2] 

机构地区：[1]长春科技大学地球科学学院,长春130061 [2]中国地质大学资源学院,武汉430074

出　　处：《地球科学（中国地质大学学报）》2001年第2期118-122,共5页Earth Science-Journal of China University of Geosciences

基　　金：国土资源部矿产资源定量预测及勘查评价开放研究实验室资助

摘　　要：川西北地区是我国主要的微细浸染型金矿化集中区之一 ,产有马脑壳等 2 0余处重要金矿床 (点 ) .研究表明 ,区内此类金矿床范围内常发育多种类型的石英脉体 ,其中黄铁矿 -毒砂 -石英脉、石英 -辉锑矿脉及石英 -雄 (雌 )黄脉与金矿化关系密切 ,是主要金矿化阶段产物 ,它们在空间上多分布于矿化带范围 ,其发育程度在一定意义上指示金矿化作用的强度 ,因而构成区内该类金矿床找矿评价的重要宏观标志 .流体包裹体研究表明 ,上述类型的石英脉主要形成于温度为 170～ 2 10℃及盐度w(NaCl)为 4%～ 11%的热液条件下 ,其热液气相成分中w(CO2 ) /w (H2 O)比值一般变化于 0 .2 40～ 0 .491,石英红外吸收光谱相对光密度D(H2 O) /D(CO2 )值一般小于 8.0 ,与其他类型石英脉具明显区别 ,因而上述参数值构成了该区金矿床找矿评价的重要石英脉微观标志 .The north-western Sichuan Province, one of the main micro-grain disseminated gold metallogenic zone in China, possesses about twenty important gold deposits (or occurrences) such as Ma'naoke etc. Studies show that several kinds of quartz veins are often developed in the mining districts in this region, among which pyrite-arsenopyrite-quartz, quartz-stibnite as well as quartz-realgar (orpiment) veins are intimately related with gold mineralization and their spatial distribution is mainly constrained in the gold mineralization belts. While the development degree of these three kinds of quartz veins can indicate gold mineralization intensity to some extent, so they are important macroscopic marks for exploration and evaluation of this type of gold deposits in the region. Studies on fluid inclusions show that these kinds of quartz veins formed in a hydrothermal condition with temperature range from 170 ℃ to 210 ℃ and salinity of fluids range from 4% to 11%, the w (CO 2)/ w (H 2O) value of the gaseous compositions of fluid inclusions is between 0.240 and 0.491 in general, and the relatively light density values of quartz are usually lower than 8.0. All these are obviously different from other kinds of quartz veins, so these parameters of quartz form the important microscopic marks for exploration and evaluation of gold deposits in the region.

关 键 词：石英脉 微细浸染型金矿床 流体包裹体 找矿标志 评价 矿化作用 

分 类 号：P618.51[天文地球—矿床学]