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文章系统研究了金堆城钼矿床的含矿钾长斑岩、围岩、矿石、矿石中的黄铁矿及矿化围岩的地球化学特征,深入探讨了矿区成矿物质的来源。金堆城含矿斑岩的稀土元素分布和特征地球化学参数显示,金堆城含矿斑岩富集LREE(LaN/YbN=5.40～16.84),轻、重稀土元素分馏较明显,Eu异常不明显或无Eu异常(δEu=0.70～0.96)。矿石中黄铁矿富集LREE(LaN/YbN=3.15～26.28),具有弱的Eu负异常,无Ce异常(δEu=0.64～0.81,δCe=0.88～1.03),并与金堆城含矿钾长斑岩和矿石具有一致的球粒陨石标准化配分曲线和特征的地球化学参数,显示金堆城钼矿床的成矿物质来源与钾长斑岩同源。矿床铅、硫、碳和氢-氧同位素地球化学综合研究表明,成矿物质来源于深部,与钾长斑岩同源。围岩在矿化和蚀变过程中元素的迁移计算结果表明,在热液成矿过程中Mo随成矿流体加入到围岩并使围岩发生蚀变和矿化。钼矿床的成矿物质主要来自钾长斑岩,围岩不提供成矿物质。金堆城含矿斑岩和钼矿化的发生处于秦岭造山带在中新生代的挤压-伸展转变期,受板片断离作用和壳幔边界附近发生的基性岩浆底侵作用影响,加厚的华北地块南缘下地壳物质发生熔融形成花岗质岩浆,并沿构造薄弱带上升到浅部侵位,形成金堆城等同熔型斑岩和斑岩型矿床。
The paper systematically studied the geochemical characteristics of the ore-bearing porphyry porphyry in the Jinduicheng molybdenum deposit, the geochemistry of pyrite and mineralized rock in the surrounding rock, ore and ore, and discussed the source of ore-forming material in the mining area. The REE distribution and the characteristic geochemical parameters of the Jinduicheng porphyry porphyry show that the Jinduicheng ore-bearing porphyry is enriched in LREE (LaN / YbN = 5.40 ~ 16.84), the fractionation of light and heavy rare earth elements is obvious, and the Eu anomaly is not Significant or no Eu anomaly (δEu = 0.70 ~ 0.96). The pyrite in the ore is enriched in LREE (LaN / YbN = 3.15-26.28) and has weak Eu anomaly without Ce anomaly (δEu = 0.64-0.81, δCe = 0.88-1.03) The long-term porphyry and ore have the same chondrite normalized distribution curve and the characteristic geochemical parameters, indicating that the metallogenic source of the Jinduicheng molybdenum deposit is homologous with the kypic porphyry. The lead, sulfur, carbon and hydrogen-oxygen isotope geochemical studies of the deposits show that the ore-forming materials are derived from the deep and are homologous to the porphyry. The calculation results of migration of elements in mineralization and alteration of surrounding rock indicate that Mo is added into the surrounding rock with mineralization fluid during the hydrothermal mineralization process and causes alteration and mineralization of the surrounding rock. The ore-forming materials of the molybdenum deposit mainly come from the porphyry of porphyries, and the surrounding rocks do not provide ore-forming materials. The occurrence of Jinduicheng ore-bearing porphyry and molybdenum mineralization is in the mid-Cenozoic extrusion-extension transition of the Qinling orogenic belt and is affected by the basaltic magma underplating caused by the detachment of the plate and the crust and mantle boundary The lower crust in the thick southern margin of North China massifacts and melts to form granitic magmatism, which rises up to shallow emplacement along the tectonic weak belt, forming the Jinduicheng equivalent melt type porphyry and porphyry deposits.