北淮阳东段铅锌矿床镉的赋存状态及其富集特征研究

Cd occurrence status and its enrichment characteristics of the sphalerite in lead-zinc deposits,eastern Beihuaiyang district

文章利用电子探针分析手段,对北淮阳东段典型铅锌矿床中Cd的赋存状态和富集特征进行了分析研究。结果表明,北淮阳东段铅锌矿床中分散元素Cd主要赋存在闪锌矿中,少量赋存于方铅矿、黄铁矿等硫化物矿物,且闪锌矿中的Cd质量分数与Zn质量分数成反比关系,表明Cd是以类质同象方式置换Zn而进入闪锌矿晶格中。北淮阳东段典型铅锌矿床中不同颜色闪锌矿与Cd质量分数的关系研究显示,Cd富集与闪锌矿颜色无明显关系。研究发现北淮阳东段铅锌矿床中闪锌矿Cd质量分数的富集程度从大到小依次为隐爆角砾岩型(汞洞冲)、矽卡岩型(银水寺)、热液交代充填型(银冲)。

This paper studied Cd occurrence status and its enrichment characteristics of the sphalerite from the typical lead-zinc deposits in the eastern section of Beihuaiyang district based on the petrographic observation and EPMA analysis.The results show that Cd resource is mainly occurred within sphalerite,with a small amount occurring in galena and pyrite.The mass fraction of Cd in sphalerite is negatively related with Zn,indicating that Cd replaces Zn in an isomorphic manner and enters the lattice of sphalerite.The statistic results suggest that there is no significant relationship between Cd enrichment in sphalerite grains and their colors.In the eastern Beihuaiyang district,the Cd enrichment of sphalerite in the lead-zinc deposits exhibits a descending trend from the explosive breccia type(Gongdongchong)to the skarn type(Yinshuisi),and then to the low-temperature hydrothermal type(Yinchong)deposits.