广西盘龙铅锌矿床硫化物电子探针分析及指示意义

Electron Probe Analysis and Indicative Significance of Sulfide in Panlong Lead-Zinc Deposit, Guangxi

广西盘龙铅锌矿床位于大瑶山西侧多金属成矿带的南段,是广西知名的中大型铅锌矿床。矿体主要赋存下泥盆统上伦白云岩地层中,主要赋矿围岩为白云岩。矿体与围岩界线清楚,铅锌矿体的延伸展布均受白云岩地层及NE向层间挤压破碎带的严格控制,矿体形态主要呈层状、似层状产出,主要的矿石矿物有闪锌矿、方铅矿、黄铁矿,脉石矿物有白云石、重晶石及石英、方解石等。本文在以矿床的地质特征基础上,对矿区内不同中段矿石的闪锌矿、方铅矿以及黄铁矿进行了电子探针分析,测定结果得出,闪锌矿中的Zn/Fe值为166.13,Fe平均含量为1.31%,反映其产出在中–浅成低温环境中。方铅矿中的Pb平均含量为85.95%,S平均含量为12.59%,表现出Pb、S亏损的特征,黄铁矿中的Fe平均含量为46.52%,S平均含量为51.63%,其Co/Ni比值小于1,说明成因类型为沉积型黄铁矿。综合矿床地质特征和硫化物电子探针分析结果,推测盘龙铅锌矿床类型为MVT矿床。

Electron probe analysis and indicative significance of sulfide in Guangxi Panlong lead-zinc deposit Located in the southern part of poly metallic metallogenic belt on the west side of Dayaoshan Mountain, Guangxi Panlong lead-zinc deposit is a well-known medium-large lead-zinc deposit in Guangxi. The ore body mainly occurs in the upper Lunian dolomite stratum of Lower Devonian series, and the main ore-bearing surrounding rock is dolomite. The boundary between orebody and surrounding rock is clear, and the extension and distribution of lead-zinc ore body are strictly controlled by dolomite stratum and NE-direction interlayer extrusion fracture zone. The orebody form is mainly stratified and stratified, and the main ore minerals are sphalerite, galena, pyrite, and gangue minerals are dolomite, barite, quartz, calcite, etc. Based on the geological characteristics of the deposit, the electron probe analysis of sphalerite, galena and pyrite in different middle ores in the mining area is carried out. The measured results show that the Zn/Fe value of sphalerite is 166.13, and the average Fe content is 1.31%, which reflects that sphalerite is produced in medium-epigenic low temperature environment. The average content of Pb in galena is 85.95%, the average content of S is 12.59%, showing the characteristics of Pb and S loss. The average content of Fe in pyrite is 46.52%, the average content of S is 51.63%, and the Co/Ni ratio is less than 1, indicating that the genetic type is sedimentary pyrite. Based on the geological characteristics of the deposit and the results of sulfide electron probe analysis, it is inferred that the Panlong PB-Zn deposit is a MVT deposit.