黔西南水银洞金矿床矿体数学特征及其勘查意义  

Mathematical Characteristics of the Ore Bodies from the Shuiyindong Carlin-Type Gold Deposit,Southwestern Guizhou Province and Implications for Mineral Exploration

作　　者：陈林杰[1] 王素平[1] 

机构地区：[1]安徽省地质矿产勘查局321地质队,安徽铜陵244033

出　　处：《地质科技情报》2011年第6期75-80,共6页Geological Science and Technology Information

基　　金：危机矿山接替资源找矿项目(200634023)

摘　　要：水银洞金矿床是黔西南地区著名的特大型微细浸染型金矿床。对矿石品位统计分布特征的分析表明,水银洞金矿床为多次成矿作用叠加的产物。通过矿石品位进行混合总体筛分获得两个单一总体,分别对应两次成矿作用,即沉积成岩期的金预富集和构造-热液期的叠加成矿,其中后者成矿强度大但不均匀,前者成矿强度小但较均匀。对矿体自相关特征的变异函数模拟结果表明,对该矿床进行勘探时可采用沿矿体走向和倾向方向布置的矩形勘探网,提出今后矿山和外围的勘探可以使用比目前网距更宽的网距,即75m×190m网距来控制矿体,这将大大降低勘探成本。矿石品位的趋势面分析结果表明,随着标高的降低,即往深部方向矿石品位的平均值和变化系数均呈现明显的下降趋势,说明往深部矿化强度减小,而矿化变得较均匀。结合矿区目前的勘探情况和趋势面分析结果,认为灰家堡背斜的北翼是矿区及其外围进一步找矿的重点区域。The Shuiyindong gold deposit is one of the largest Carlin-type gold deposits in a well-endowed gold district in southwestern Guizhou Province.Statistical analysis shows that gold grades of the ores are characterized by a typical mixture distribution,indicating two distinct stages of mineralization.The first stage reflects pre-enrichment of gold in framboid pyrite formed during diagenesis of the host rocks,whereas the second stage represents overprint of auriferous fluids,likely in the Early Cretaceous.This interpretation is consistent with previous geological and petrographic observations.The second stage mineralization is dominant in terms of gold resource of the deposit.Results from modeling of spatial variation for gold ore bodies indicate that it is more appropriate to use an exploration grid of 75 m×190 m,much less dense than the present exploration grid,and therefore more economic.Trend analysis of the ore grade data reveal that both the mean and variation of gold grade are decreasing towards depth.This implies that gold mineralization tends to diminish but is more homogeneous.When combined with existing data,results from this study suggest that the area of the north limb of the Huijiabao anticline is the important potential target in the future exploration.

关 键 词：矿石品位 数学特征 混合分布 变异函数 趋势面分析 水银洞金矿床 

分 类 号：P618.51[天文地球—矿床学]