【作者】 张之武；

【导师】 彭齐鸣； 李惠；

【作者基本信息】 中国地质大学（北京） ， 矿物学、岩石学、矿床学， 2014， 博士

【摘要】 大王顶金矿是广西古袍金矿田中新发现的重要金矿床之一。本研究密切结合该矿山生产建设和深部找矿需求，在综合研究成矿地质地球化学背景及矿床地质特征的基础上，对大王顶金矿开展了构造叠加晕和成矿预测研究。取得以下主要成果：1、矿区内大王顶岩体与近EW和NE的断层控制了矿体三维空间形态。矿体整体上近东西走向，倾向在大王顶花岗斑岩体以北，主要是北西和北北西倾；以南，主要是西倾。2、计算了大王顶金矿围岩10件背景样品的几何平均值，获得了矿山指示元素地球化学背景，为构造叠加晕研究的异常分带提供了依据。3、在大量系统的样品采集和化学分析基础上，研究了矿床元素组合及不同阶段元素地球化学特征；在三维空间内，制作了各元素构造叠加晕系列图件，为原生晕轴向分带变化规律分析奠定了基础。编制了能够反映成矿流体活动规律的系列元素分布图，以此为依据，对矿体进行了重新圈定，较好地揭示了矿体的分布规律。4、编制了系列构造叠加晕剖面图和纵投影图，对前缘晕、近矿晕和尾晕进行了剥离解析，近矿晕元素组合为Au、Ag、Cu、Pb，前缘晕元素组合为As、Sb、Hg和尾晕元素组合为Mo、Bi；多期次成矿叠加晕表现为：Au具有一个或多个强异常中心，不同期次成矿过程形成的矿体-晕在构造空间上有同位-近于同位-部分同位-或只有上部矿尾晕与深部盲矿前缘晕叠加等复杂的叠加结构，揭示了热液化学晕的叠加规律，建立了该矿床的构造叠加晕模型：认为大王顶金矿床构造叠加晕模式最佳指示元素组合为：Au、Ag、As、Sb、Hg、Cu、Pb、Zn、Bi、Mo；确定了盲矿预测的构造叠加晕标志。5、根据盲矿体预测的标志，提出了41个盲矿预测靶位和1个有利成矿部位。6、大王顶金矿矿体所研究的元素衬度值明显低于已知的其它研究实例金矿，显示出该金矿成矿热液活动不强烈，成矿规模相应较其它研究矿山小。大王顶金矿在大瑶山金矿成矿区具有很好的代表性，本研究为矿山下一步生产及勘查指明了方向，且对于该成矿区其它金矿具有较好的借鉴意义。由于大王顶金矿目前仅有三个中段，中段少导致从巷道采集样品数量少，且矿区内存在破矿构造，使其控矿规律更加复杂，加剧了样品代表局限性，导致对矿床地球化学特征研究局限性的存在。建议随着矿山中段增加，继续跟踪研究。此外，构造叠加晕模型是建立在就矿找矿和对已有数据统计分析基础上。该模式虽在生产实践中显示了强大的生命力，但由于各种地质因素共同作用下成矿过程的复杂性，热液矿床原生晕分带形成的机制等，需要在今后进一步加强理论研究。更多还原

【Abstract】 The Dawangding gold deposit located in the Gupao Town of Zhaoping County, is one ofthe most important and newly discovered gold deposits in the Gupao gold ore field. In order tofigure out the distribution of the ore body and the potential of the resources, structuralsuperimposed halo and metallogenic prognosis study of the Dawangding gold deposit aresystematacially carried out in this dissertation. Combined with comprehensive study of itsdeposit geology and ore-forming geochemical background, the following achievements areobtained.1. In the mining district, three-dimensional morphology of the ore body is controlled bythe Dawangding intrusion, nearly EW-striking and NE-striking faults. The ore body strikesnearly EW, with the trend of W and NNW in the north of the Dawangding intrusion, whereasin the south it turns into west.2.According to computing the geometric mean of10background samples from the wallrock in the mine, the elements of Bi, As, Au, Pb, Sb, W, Sn, Ba and Ag are enriched. Andthrough doing this, the geochemical background of the indicator elements are obtained, whichprovides the standard for the structural superimposed halo anomaly analysis.3.Based on systematic collection of709samples and analysis of their contents of18elements, the element assemblage and their quantitative geochemical characteristics of theDawangding gold deposit have been obtained. A series of structural superimposed halo chartsof each element have also been made in the three-dimensional space, which lay the foundationfor variation analysis on the axial zoning of the primary halo. We have also made distributioncharts of the18elements in order to reflect activity rule of the ore-forming fluid. Based on this,the ore body has been delineated again, which can better reveal the distribution of the orebody.4.Section and vertical projection drawings of the structural superimposed halo inDawangding gold deposit have been made. The corresponding metallogenic pattern of headhalo, near-ore halo and tailing halo has also been set up.The near-ore halo is composed ofAu、Ag、Cu、Pb, the head halo ofAs、Sb、Hg and the tailing halo of Mo、Bi. TheAu element hasone or more abnormal centers. The halo of the ore body, derived from different ore-formingprocessed, is characterized by apposition, or near apposition, or part apposition, or some ofthem is characterized by superimposed structure of the hailing halo of the upper ore and the head halo of the blind ore. This helps to better reveal the superimposed rule of thehydrothermal halo and also to build the structural superimposed halo metallogenic pattern inthe Dawangding gold deposit. Thus, we suggest that the best indicator elements of theDawangding gold ore body are Au, Ag, As, Sb, Hg, Cu, Pb, Zn, Bi, and Mo, which helps toconfirm mark of the structural superimposed halo used to predict the blind ore.5. According to the above indicative mark of the blind predicting, the prospecting targetsof41blind ore and one favorable ore-forming location have been proposed.6.The contrast values of the18elements studied in the Dawangding gold deposit aresignificantly lower than the other known gold mines. This shows that the metallogenichydrothermal activity is not strong in the Dawangding gold deposit, and thus indicates that themineralization scale is smaller than other mines studied before.As a representative in the Dayaoshan gold metallogenic region, structural superimposedhalo study of the Dawangding gold deposit provides a great help for the next exploration ofDawangding deposit and also for the other gold mines in the area. But there are only threedifferent middle sections, resulting in that the samples collected from the tunnels are notenough. Besides, there are also structures destroying the ore body, so the ore-controllingregularity is more complex and the representative samples are limited. All of the above factorslimit in-depth study of the geochemistry of the Dawangding deposit. It is suggested that thetracking study should be continued with the increasing of the mining middle sections. Inaddition, the structural superimposed halo metallogenic pattern is prospecting of unknown oresbased on the known ore deposits, which also needs to statistically analyze the existing data. Inconclusion, although the pattern has been widely used in many gold mines, it also needsfurther theoretical study for improving because of the complexity of the ore-forming processin various geological factors and aslo the complex formation mechanism of the primary halozone in hydrothermal deposits, etc.更多还原