【作者】 蔡爱良；

【导师】 刘亮明；

【作者基本信息】 中南大学 ， 矿产普查与勘探， 2009， 博士

【摘要】 西昆仑地区是地质研究程度很低,却蕴含着巨大资源潜力的成矿区带。塔木—卡兰古铅锌铜矿带是西昆仑成矿区带的重要组成部分,是当前找矿勘查和成矿研究的热点地区,前人取得了不少找矿和研究成果,但这一区域的各级构造控矿规律一直是研究的薄弱环节,并制约了成矿预测及矿产勘查。正是基于这一背景,笔者在阿克陶县桂新矿业开发有限责任公司的支持下,选择“西昆仑塔木—卡兰古铅锌铜矿带多级构造控矿模式及成矿预测”进行专题研究。持续四年的研究工作主要包括：从区域地球物理和区域遥感分析区域构造格架及其对成矿的控制；从构造几何学和构造动力学分析矿田和矿床构造特征及其对成矿的控制；从矿床地质和地球化学特征分析矿床成因；在创新构造成矿动力学模式的基础上结合地球化学和地球物理找矿信息进行成矿预测。通过这些工作主要获得了如下9个方面的成果。(1)从区域岩石建造和构造变形特征阐述了塔木—卡兰古铅锌铜矿带地壳演化历经了超大陆裂解、板块俯冲、裂陷槽发育至闭合、造山挤压、盆山分异几个构造演化阶段,多期次的构造运动是造成矿带成矿特征复杂的主要原因。(2)ETM遥感图像显示塔木—卡兰古铅锌铜矿带处于NNW向区域性断裂构造带中,矿带的边界为两条NNW向边界断层,其地质特征显示出多期次复杂活动之性质,表明整个矿带构造控制的重要性和复杂性。(3)通过区域尺度、矿田尺度、矿床尺度和矿体尺度的构造特征及其与成矿间关系的分析,首次建立了四级构造控矿模式,即工级的NNW向克孜勒陶—库斯拉甫断裂控制了整个塔木—卡兰古铅锌铜矿带；Ⅱ级NNW向断裂与EW向断裂共同控制了矿田；NNW向Ⅱ级断裂所派生Ⅲ级断裂控制矿床；Ⅳ级的裂隙带、节理等构造控制富矿体。(4)通过对矿体地质的详细解剖,首次发现铅锌富矿体严格受近EW向的裂隙带控制,并将这一新发现规律应用于塔木、阿拉尔恰和卡拉牙斯卡克等矿床的探采工程,工程控矿效率提高了一倍,出矿品位提高了30%以上。(5)首次对塔木铅锌矿主矿体及相关断层F10、裂隙带等地质要素进行了三维形态模拟,更加清晰地揭示了矿体与构造之间的空间关系,表明NNW向断层F10控制了主矿体,F10派生的近EW向裂隙带控制了富矿体。(6)根据典型矿床的地质地球化学特征进一步论证了本区铅锌矿床为MVT,推测成矿物质来源于前泥盆系等上地壳层位；成矿流体主要由以大气降水为补给的深部热卤水及油田卤水的混合；流体为中低温、中高盐度；成矿元素以硫氢配合物形式迁移；成矿流体运移的最主要驱动力来源于构造运动。(7)从区域成矿规律和区域地壳演化规律论证了本区铅锌铜的主要成矿作用是喜马拉雅期造山运动的逆冲推覆所致,首次建立逆冲推覆构造成矿模式。(8)根据矿体的构造控矿模式和高频大地电磁测深(EH4)测量结果,预测了塔木主矿体(Ⅰ号矿体)深部的延伸变化,3个验证钻孔都证实了预测结论,储量接近翻番。应用构造控矿模式对阿拉尔恰和卡拉牙斯卡克的矿体预测也得了工程的证实,新增资源储量达12万吨铅+锌。(9)根据区域构造控矿模式,结合区域地球化学勘查结果进行区域成矿预测分析,圈定了2个A类预测靶区和一个B类预测靶区。更多还原

【Abstract】 The West Kunlun region is poor understood but abundant in mineral resources, where the Tamu-Kalangu Pb-Zn-Cu ore belt, as one of its most important components, is becoming focus of exploration and research recently. However, the rules and ore-controlling mechanism of multi-scale structure on metallogeny in this region are not researched well enough for facilitating predictive exploration.Based on this background, supported by the Guixin Mineral Ltd., the author proceeded monographic study on model of multi-scale structural-controlling on ore formation and metallogenic prediction in Tamu-Kalangu Pb-Zn-Cu ore belt of West Kulun.The research includes analyzing the area structural architecture and its control on mineralization by regional geophysics and remote sense, analyzing the features of field-scale and deposit-scale structure and their control on mineralization by structural geometry and structural dynamics, deducing mineral deposit origin by analyzing mineral deposit geological and geochemical characteristics, conducting metallogenic prognosis based on innovating structural mineralization dynamics and prospecting information of geochemistry and geophysics. The research outcome mainly includes:(1) According to regional petrographic formation and structure distortion characteristics, Tamu-Kalangu Pb-Zn-Cu ore belt has experienced several orogenic stages including dehiscence of the supercontinent, plate subduction, rift trough growth to closure, orogenic extrusion, basin mountain differentiation. Complex mine belt mineralization characteristic is mainly due to multi-stages tectonic activity.(2) The ETM remote sensing image shows that West Kunlun Tamu-Kalangu Pb-Zn-Cu ore belt lies in regional fracture structural belt of NNW, on the boundary, there are two border faults of NNW, its geologic characteristic shows multi-stages tectonic activity and entire ore belt structural controlling significance.(3) By analyzing structural characteristics and their mineralization relationship of region scale, ore field scale, deposit scale and ore body scale, a four scales ore-controlling model is first established, that is,Ⅰ-NNW Keziletao-Kusilafu fracture controls whole Tamu-kalangu Pb-Zn-Cu ore belt;Ⅱ-NNW fracture together with EW fracture controls the ore field;Ⅲ-a series of secondary fractures related with II controls deposit;Ⅳ-rich ore body is controlled by zone of fracture and rock joint, etc.(4) By detailed dissection for ore body geology, it is first detected that Pb-Zn bonanza is rigorously controlled by EW zone of fracture. Moreover, after applying the new discover in exploring and mining engineering in the Tamu, Alaerqia and Kalayasikake mines, the rate of measuring ore reserves by engineering has been doubled, grade of ores mined has been increased about 30%.(5) The 3D morphology of main orebody, F10 fault and fracture zone in the Tamu Pb-Zn mine are first simulated, which more clearly reveals positional relation of orebody and structure. The result demonstrates that NNW fracture F10 controls main orebody, and EW zone of fracture derived F10 controls rich ore body.(6) On the basis of geological and geochemical characteristics of the typical ore deposits, it is further demonstrated that the Pb-Zn ore deposits in this district is MVT; and ore-forming elements are original from the upper crust horizon such as pre-devonian; the high salinity ore-forming fluids are mixture of oil field brine and deep hot brine recharged by meteoric water in middle-low temperature; migration with bisulfide complex form; the main driving force in migration of ore forming fluids origins tectonic stress.(7) By analyzing the regularities of regional metallogeny and crustal evolution, it is demonstrated that main mineralization of Pb-Zn-Cu is caused by thrusting of Himalayan orogenic movement, the mineralization model of thrust nappe structure is first built up.(8) According to the structural metallogenic model and EH4 surveying results, the deep extension of Tamu main ore body is predicted. The prediction has been confirmed by 3 drill holes and the reserves increased almost double. The ore prediction by structural mineralization models in the Alaerqia and Kalayasikake is also confirmed by exploration engineering and new about 120,000 tons of Pb and Zn have been discovered.(9) By using of the model of the regional structural controlling on mineralization and regional geochemical exploration results, regional metallogenic potential is predicted and two target-areas of first-order and and one target-area of second-order have been delineated.更多还原