辽宁青城子钼—铅锌—银矿床硫化物标型特征研究

发布时间：2018-02-17 06:36

本文关键词： 辽宁青城子铅锌多金属硫化物矿物标型　出处：《中国地质大学(北京)》2017年硕士论文　论文类型：学位论文

【摘要】：辽宁青城子矿集区位于辽东裂谷轴部,是辽东-吉南成矿带一个重要的钼-铅锌-金银矿田。本文以新岭钼矿、榛子沟脉状铅锌矿、高家堡子银矿为典型矿床,通过电子探针(EPMA)、热电性、LA-ICP-MS等手段对硫化物矿物进行了系统的标型研究和对比,总结了该区硫化物的矿物标型特征,以此探讨矿床的成因模式,并对矿区可能的成矿靶区进行推测。青城子铅锌矿中的黄铁矿的热电系数基本上为P型,偶见零星N型黄铁矿出现。P型黄铁矿的热电系数变化范围为0~350μV/K,集中区在250~350μV/K之间。主成矿期近一半的黄铁矿没有热电性,同时该时期的方铅矿基本没有热电性。青城子矿田内早期自形黄铁矿Co/Ni比值指示其为沉积成因,而后期与方铅矿,闪锌矿交互共生的黄铁矿主要为热液成因;As与S呈正相关性,As与Fe呈微弱的负相关性,主成矿期应该的岩浆热液为氧化环境。铅锌矿和银矿中方铅矿的S,Pb含量相似,钼矿中方铅矿的S,Pb含量明显升高,方铅矿中Bi含量均是极低,基本趋近于0,指示方铅矿整体的形成温度较低。闪锌矿中Fe含量和Zn含量存在良好的负线性相关关系,说明Fe呈类质同象方式替代Zn。铅锌矿床与银矿床中的闪锌矿形成在中温环境下,而钼矿床中的闪锌矿形成在较高的温度下。研究区黄铁矿亏S,闪锌矿和黄铜矿整体富S,矿区东部方铅矿呈现亏S现象,As、Sb、Te对S的替换显示成矿热液来源有深部幔源成分,显示成矿过程中有地幔物质参与。青城子矿集区方铅矿、闪锌矿、黄铜矿和黄铁矿都表现出明显的主要金属离子亏损性质,这与该区硫化物发生大量类质同象替换行为有关。成矿流体应从矿区西北区即姚家沟新岭岩体向矿区东南部运移,形成中心斑岩-夕卡岩钼矿、中间夹着大量中低温铅锌矿床、外缘浅成低温金、银矿的组合。新岭岩体向南可能是寻找印支期岩浆热液成矿型铅锌矿床的主要方向,而姚家沟和新岭岩体边缘处是钼矿的找矿靶区。
[Abstract]:Qingchengzi ore concentration area in Liaoning province is located at the axis of Liaodong rift valley and is an important molybdenum, lead-zinc-gold-silver ore field in the Liaodong-Jinan metallogenic belt. In this paper, Xinling molybdenum deposit, hazelnut trench vein lead-zinc ore deposit and Gaojiapuzi silver deposit are typical deposits. The systematic typomorphic study and comparison of sulfide minerals were carried out by means of EPMA, thermoelectric and LA-ICP-MS, and the characteristics of sulfide minerals in this area were summarized, and the genetic model of the deposits was discussed. The thermoelectric coefficient of pyrite in Qingchengzi lead-zinc deposit is basically P type. Occasionally, the variation range of the thermoelectric coefficient of the pyrite is 0 ~ 350 渭 V / K, and the concentration area is between 250 ~ 350 渭 V / K. Nearly half of the pyrite in the main metallogenic period has no thermoelectric property. At the same time, the galena in this period had little thermoelectric property. The Co/Ni ratio of autotype pyrite in Qingchengzi Orefield indicated that it was of sedimentary origin, while in late stage, it was associated with galena. The pyrite in sphalerite is mainly hydrothermal origin with positive correlation between as and Fe. The magmatic hydrothermal solution in the main ore-forming period is oxidized environment. The content of lead Pb in lead zinc ore and galena is similar to that in silver ore. The content of lead in galena is obviously increased, and the content of Bi in galena is very low, which indicates that the formation temperature of galena is low. There is a good negative linear correlation between Fe content and Zn content in sphalerite. The results show that the sphalerite in Zn. Pb-Zn and Ag deposits is replaced by Fe in a metamorphic manner, and the sphalerite is formed in a medium temperature environment. The sphalerite in the molybdenum deposit is formed at a higher temperature. In the studied area, pyrite deficiency, sphalerite and chalcopyrite are rich in the whole body. The replacement of S for S in galena in the eastern part of the ore area shows that the ore-forming hydrothermal source is of deep mantle origin. It is shown that mantle material is involved in the metallogenic process. Galena, sphalerite, chalcopyrite and pyrite in Qingchengzi ore concentration area all show obvious major metal ion depletion properties. This is related to the occurrence of a large number of metamorphic replacement behavior of sulfides in this area. The ore-forming fluids should be migrated from the northwest of the mining area to the southeast of the mining area, forming a central porphyry skarn molybdenum deposit with a large number of medium-low temperature lead-zinc deposits in the middle. The combination of epithermal gold and silver deposits on the outer margin may be the main direction of searching for the Indosinian magmatic hydrothermal ore-forming lead-zinc deposits in the south, while the margin of the Yao Jiagou and Xinling pluton is the prospecting target of the molybdenum deposit.
【学位授予单位】：中国地质大学(北京)
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：P618.2

【参考文献】