华北克拉通南缘晚中生代钼、金成矿关系:以祁雨沟金矿床和雷门沟钼矿床为例  

Genetic Links Between Late Mesozoic Mo Deposits and Au Deposits in the Xiong’ershan Area,Southern Margin of the North China Craton:A Case Study of Leimengou Mo Deposit and Qiyugou Au Deposit

作　　者：詹强 吴强 陈程[1,2,3] 孟雷 赵太平[1,3] ZHAN Qiang;WU Qiang;CHEN Cheng;MENG Lei;ZHAO Taiping(Key Laboratory of Mineralogy and Metallogeney,Guangzhou Institute of Geochemistry,Chinese Academy of Sciences,Guangzhou 510640,Guangdong,China;University of Chinese Academy of Sciences,Beijing 100049,China;CAS Center for Excellence in Deep Earth Science,Guangzhou 510640,Guangdong,China;State Key Laboratory of Ore Deposit Geochemistry,Institute of Geochemistry,Chinese Academy of Sciences,Guiyang 550081,Guizhou,China)

机构地区：[1]中国科学院广州地球化学研究所矿物学与成矿学重点实验室,广东广州510640 [2]中国科学院大学,北京100049 [3]中国科学院深地科学卓越创新中心,广东广州510640 [4]中国科学院地球化学研究所,矿床地球化学国家重点实验室,贵州贵阳550081

出　　处：《大地构造与成矿学》2023年第6期1267-1290,共24页Geotectonica et Metallogenia

基　　金：国家自然科学基金项目(41872088);矿床地球化学国家重点实验室开放研究基金项目(201806)联合资助。

摘　　要：华北克拉通南缘是我国重要的钼、金成矿带之一,已探明的钼资源量超过800万吨,金资源量超过1300吨。前人研究表明,区内金成矿事件多发生于晚侏罗世‒早白垩世(160~110 Ma),与区内大规模的钼成矿事件(148~112 Ma)及岩浆侵位事件(158~112 Ma)时代相近,且三者在空间上紧密相关,但关于金与钼的成矿关系尚不清楚。本文以位于华北克拉通南缘熊耳山矿集区紧邻的早白垩世祁雨沟金矿床和雷门沟钼矿床为研究对象,分析钼与金的成矿关系。通过对两个矿床中含矿斑岩体中的磷灰石进行详细的主量和微量元素分析,结合前人已有的地球化学资料,认为形成于130 Ma的祁雨沟花岗斑岩与雷门沟花岗斑岩具有相似的母岩浆,但后者的氧逸度和分异程度更高,且相对更富F、贫Cl和S;H-O-S-Pb同位素组成表明,钼与金矿床的成矿流体主要为岩浆热液,成矿物质钼、金均来源于壳幔混合源区,但相对于钼矿床,金矿床的幔源组分所占比例更高。研究区内的钼、金成矿作用受不同演化阶段的岩浆岩控制;造成钼、金差异性矿化的根本原因可能是成矿岩体的性质和金属来源不同,金主要与幔源物质相关,钼主要与古老地壳物质相关。The southern margin of the North China Craton(NCC)is the largest Mo-Au polymetallic belt in China,which contains more than 8 million tons Mo and more than 1300 tons Au.The gold deposits in the belt were mostly formed in the Late Jurassic to Early Cretaceous(160–110 Ma),which are roughly contemporaneous with the spatially closely related large-scale Mo mineralization(148–112 Ma)and granite magmatism(158–112 Ma).Extensive studies in this regard have been conducted,however,the relationship between the Au mineralization and the Mo mineralization remains unclear.The closely spatiotemporal related Qiyugou Au deposit and Leimengou Mo deposit in the Xiong’ershan ore district were formed in the Early Cretaceous.Thus,we chose the two deposits as the research objects to investigate their genetic links,aiming to obtain a better understanding of the metallogenic relationship between molybdenum and gold in this region.Based on detailed analysis of major and trace elements of apatite,combined with the available geochemical data,it is considered that the Qiyugou and the Leimengou granite porphyries were formed in 130 Ma and derived from similar magma source.The oxygen fugacity and degree of magmatic differentiation for the Leimengou granite porphyry are relatively higher,the volatile is relatively rich in F,but poor in Cl and S.The H-O-S-Pb isotopic data of the Mo and Au deposits show that the ore-forming fluids of the Late Mesozoic Mo deposits and Au deposits in the southern margin of the North China Craton are predominantly derived from a magmatic source,the Mo and Au deposits originated from mixed crust-mantle sources.Furthermore,these data suggest that the source of the Au deposits contain more mantle component than that of the Mo deposits.From these results,it can be concluded that the Mo-and Au-related granites are the products of similar magma in different evolution stage.The nature of the ore-related intrusions and metal sources likely play an important role in mineralization types.In detail,mantle-derived compon

关 键 词：华北克拉通南缘 晚中生代 祁雨沟金矿床 雷门沟钼矿床 磷灰石 

分 类 号：P612[天文地球—矿床学] P597[天文地球—地质学]