【作者】 李金超；

【导师】 钱壮志； 贾群子；

【作者基本信息】 长安大学 ， 矿产普查与勘探， 2017， 博士

【摘要】 东昆仑地区位于青藏高原东北部,是我国金矿富集区之一。该区构造—岩浆活动强烈,成矿条件优越,已发现金矿床(点)多处,具有良好的找矿前景。本文以东昆仑地区构造—岩浆—成矿作用为研究主线,通过选取典型金矿床、与金矿成矿有关的中酸性岩体进行系统野外观察和室内综合研究,结合同位素年代学及同位素地球化学研究等,探讨典型金矿床的成因及其形成的构造背景;分析区内金矿床的形成时代、成矿物质来源;总结该区金矿的主要控矿因素。根据地质、地球物理以及地球化学信息等,建立区域找矿模型并圈定金矿找矿远景区,为下一步勘查部署提供依据。本文主要研究内容与进展为:1.东昆仑构造带经历了漫长而又复杂的古陆核形成、大陆裂解、俯冲碰撞、陆内伸展等地质演化过程,其中晚古生代—早中生代构造—岩浆作用是区内金等内生金属成矿的主要控矿因素。2.获得阿斯哈等5处与金矿床形成具有重要关系的中酸性岩体成岩年龄,同时获得瑙木浑金矿床成矿年龄数据。系统分析中酸性岩体与成矿的关系,结合前人已获得成矿年龄数据,认为印支期是东昆仑地区主成矿期。3.东昆仑深大断裂对不同类型的沉积建造和岩浆建造的分布有控制作用,从而也制约不同类型矿床与成矿带的分布。次级断裂控制金矿床的产出,两组或多组断裂交汇处往往是矿体产出部位,矿体的形态、产状、规模严格受构造控制。4.该区金矿床主要类型为蚀变岩型和石英脉型金矿。本文系统总结了昆北、昆中、昆南、阿尼玛卿及巴颜喀拉成矿带的空间分布规律,并对各带金矿床的类型、成矿元素组合及成矿温度的差异性等进行了分析。5.建立了东昆仑地区金矿区域找矿模型,并进行成矿预测,圈定了成矿远景区27个,其中A类6个,B类8个、C类13个,并在野外实际工作中对B2成矿远景区进行验证。更多还原

【Abstract】 Located in northeast of the Tibetan Plateau,East Kunlun is one of the gold enrichment areas in China.There is strong tectonic-magmatic activity,superior metallogenetic conditions and good prospecting potential in East Kunlun,where a number of gold deposits(points)formed.In this paper,taking the tectono-magmatic-mineralization in East Kunlun as the main line of research,by systematic field observation and detailed laboratory study on the typical gold deposits and intermediate-acidic rocks related to gold mineralization,combined with isotopic chronology and geochemistry,I discuss the genesis and tectonic background of typical gold deposits,analyze the formation age and metallogenic material source of the gold deposits,and summarize the main ore-controlling factors of gold deposits in East Kunlun.According to the geological,geophysical and geochemical information,the regional prospecting model and the prospecting potential areas of gold deposits are established to provide basis for the next exploration and deployment.The main study contents and progress of this paper are as follows:1.The eastern Kunlun tectonic belt experienced a long and complex geological evolution process,such as the formation of ancient continent nucleus,continental breakup,subduction-collision and intracontinental extension.The tectonomagmatism in Late Paleozoic–Early Mesozoic is the main ore-controlling factor of the endogenetic metal such as gold mineralization in East Kunlun.2.Five diagenetic ages of intermediate-acidic rocks such as Asiha are obtained,which have important relationship with the gold deposits,and the metallogenic age data of Naomuhun gold deposit is also obtained.Systematically analyzing the relationship between intermediate-acidic rocks and mineralization,combined with the metallogenic ages which predecessors have obtained,the author considers that Indosinian is the main metallogenic epoch in East Kunlun.3.The deep-large faults in East Kunlun usually control the distribution of different types of sedimentary and magmatic formation,and also restrict the distribution of different types of mineralization and metallogenic belts.The secondary faults control the occurrence of gold deposits,and ore bodies often occur in the intersection of two or multiple sets of fracture.The shape,occurrence and scale of gold ore bodies are strictly controlled by the structure.4.Altered rock type and quartz vein type are two main types of gold deposits in East Kunlun.The spatial distribution of metallogenic belts,such as northern Kunlun,mid-Kunlun,southern Kunlun,A’nyemaqen and Bayan Har,are summarized systematically,studying the types,ore-forming elements association and difference of metallogenic temperature of gold deposits in different belts.5.The regional prospecting model of gold deposits in East Kunlun is established,the metallogenic prognosis is carried out and 27 metallogenic prospective areas are delineated,including A type 6,B type 8,C type 13,furthermore verified in the field.更多还原