河南栾川冷水—赤土店钼钨铅锌多金属矿床特征及成矿潜力

Geological Characteristics and Genesis Regional Prospecting Potential of Lengshui-Chitudian Mo-Pb-Zn Deposit in Luanchuan,Henan Province

河南栾川冷水—赤土店钼钨铅锌多金属矿位于华北陆块南缘金银多金属成矿带上的栾川钨钼矿集区内,以野外地质调查、物探、钻探等为主要技术手段,在矿区开展了地质勘查及研究工作,共圈定了钨钼矿体8条,提交钼资源量631.17万t,WO_(3)138.28万t,钼钨资源量达超大型规模。对矿区地质特征、矿床地质特征及成因进行了详细探讨。根据矿体特征、控矿因素、矿化类型,结合前人在该区开展的硫同位素分析和含矿斑岩的SHRIMP、辉钼矿Re-Os同位素年龄成果,综合研究认为:(1)该矿床主要赋存地层为官道口群白术沟组和栾川群三川组、南泥湖组、煤窑沟组;(2)矿化以钼矿化为主,钼钨矿体主要受深部侏罗纪末花岗岩基和逆冲推覆构造体系的联合控制,燕山期中酸性侵入岩(小岩体)与区内钼钨等成矿联系密切,花岗质岩浆为钨钼等成矿元素的主要来源,含矿斑岩为主要成矿地质体;(3)含矿岩浆在运移过程中由于温度变化和围岩的差异,从而使不同的成矿元素组合出现明显的分带现象,并形成不同类型的矿化(床),矿床成因类型为斑岩—矽卡岩型,成矿时代为135~157 Ma。在上述分析的基础上,建立了钨钼铅锌多金属矿的成矿模式和综合找矿模型,对于栾川及豫西地区钼钨矿的找矿工作有一定的参考价值。

Lengshui-Chitudian Mo-Pb-ZnDeposit locates in Luanchuan ore concentrating area,which is a part of metallogenic belt at south margin of North China ContinentalBlock.Taking field geological survey,geophysical exploration and drilling as the main technical means,geological exploration and research work has been carried out,then the eight molybdenumwolfram-molybdenum orebodies have been delineated in the mining area,and the deposit reach super-large ore deposit scale.The geological characteristics of the mining area,geological characteristics of the deposit and deposit genesis are discussed in detail.According to the orebodies characteristics,ore-controlling factors and mineralization types,and combing with the achievements of the predecessors are utilized,such as molybdenite Re-Os age,sulphur molybdenite Re-Os age and SHRIMP of ore-bearing porphyry,the comprehensive study is done.The results show that:(1)The deposit is mainly distributed in Baishugou Formation of Guandaokou Group,Sanchuan Formation,Nannihu Formaiton and Meiyaogou Formaiton of Luanchuan Group.(2)The major mineralization typis molybdenum mineralization,and the orebodies are controlled by granitic batholith and thrust nappe structure together.The molybdenum-tungsten orebody is mainly controlled by the combination of the Late Jurassic granite base and the thrust nappe tectonic system.Yanshan intermediate acid intrusive rock(small rock mass)is closely related to molybdenum and tungsten mineralization in the area,granitic magma is the main source of metallogenic elements such as tungsten and molybdenum,and ore-bearing porphyry is the main metallogenic geological body.(3)Due to the difference of temperature and surrounding rock during the migration of ore-bearing magma,different ore-forming element assemblages appear obvious zoning phenomenon and form different types of mineralization(deposit).The genetic type of the deposit is porphyry-skarn type,and the metallogenic age is 135~157 Ma.Based on the above analysis results,the metallogenic model and integrated prospecting model of W-Mo-Pb-Zn polymetallic deposit are established,which is of certain reference significance to the prospecting of W-Mo deposit in Luanchuan County and Western Henan Province.