【作者】 周余国；

【导师】 刘继顺；

【作者基本信息】 中南大学 ， 矿产普查与勘探， 2009， 博士

【摘要】 滇东南地区是我国著名的卡林型金矿集中区——滇黔桂“金三角”之一角,对该区卡林型金矿的系统研究目前仍显不足。本文以板块构造理论、区域成矿学、地球化学、成矿预测学和找矿系统工程学为指导,基于十余年滇东南地区的金矿找矿实践,以大量地质地球化学数据为支撑,以滇东南地区卡林型金矿不同亚类典型矿床解剖为切入点,以成矿系列的概念将本区金矿与钨锡、铜铅锌银、砷锑汞(钡)等矿产时空分布上连成一线,以卡林型金矿成矿作用、成矿规律、成矿预测为主线,系统研究了滇东南地区卡林型金矿地质地球化学特征、控矿要素和成矿规律,并开展成矿预测。论文工作重点是以区域成矿学为主的多学科的综合研究,取得的主要成果和认识如下:1、结合对卡林型金矿研究现状的探讨,提出了卡林型金矿的再定义问题,将卡林型金矿定义为区带上集中分布的(超)微细、浸染、中低温热液金矿床。2、运用地物化遥等资料系统论述了滇黔桂菱块体(“金三角”)区域成矿地质背景,肯定了右江裂谷带(幔隆带)的存在,论证了滇黔桂“金三角”地区卡林型金矿的物源主要与裂谷和区域性深大断裂附近峨眉地幔柱长期活动相伴的基性火成岩及火山碎屑浊流沉积有关,区域构造运动及其与之相伴的酸性和基性岩浆活动是滇东南地区乃至滇黔桂地区金矿成矿作用最为主要的热源。3、论证了南盘江盆地的形成与演化,是印度板块、欧亚板块、太平洋板块相互碰撞导致地幔上隆引起玄武岩喷溢和水平拉伸在构造薄弱地段造成差异性下陷的结果,从区域地层地球化学角度指出右江裂谷活动至少始于寒武纪,随着时间的推移,由桂西北逐渐影响到滇东南及黔西南。4、对滇东南地区卡林型金矿地质特征作了概略性介绍,根据金矿的产出特点、容矿岩石等将滇东南地区卡林型金矿分为细碎屑岩-不纯碳酸盐岩型、不整合面型、基性岩型、红色粘土型。探讨了滇东南地区卡林型金矿与含金建造、岩浆岩、构造的关联,并以典型金矿床为例阐述了该区卡林型金矿的常量元素、微量元素、稀土元素、包裹体、同位素和黄铁矿单矿物等地球化学特征。5、系统论述了滇东南地区卡林型金矿成矿作用,指出壳幔不均一性及其相互作用→预成矿作用→成矿作用→后成矿作用是大自然对壳幔物质所进行的一系列“选矿”过程,各种成矿作用之间既相互联系又递进发展。提出了“预成矿作用”的概念、可能性及其对卡林型金矿等中低温矿产成矿作用的重要影响。从地球化学角度探讨了金的迁移沉淀机制。6、用成矿系列的理论将滇东南地区的金矿与钨锡、铜铅锌银、金砷锑汞等矿产进行时空上的关联,提出滇东南地区主要存在如下成矿系列组合:①越北古陆北缘与南盘江盆地演化相关联的预成矿系列组合;②与峨眉地幔柱活动相关联的中低温成矿系列组合;③与燕山期花岗岩浆活动、区域构造运动相关联的叠加改造成矿系列组合。7、提出了滇东南地区卡林型金矿矿床成因的三因素:(1)壳幔的不均一性及地球从起始演化到现今的过程中元素的分布再分配是形成矿种区域空间分布差异的基础因素;(2)预成矿作用是滇东南地区主要沿加里东不整合面形成不整合面型金矿的重要因素。(3)越北古陆的向北逆冲推覆和几大板块平移走滑所形成的驱动热力和与此相关的断褶带、层间破碎带及岩体外围由岩浆侵位、冷缩形成的密集张裂带是滇东南乃至滇黔桂“金三角”地区卡林型金矿及其他内生矿产形成的决定因素,进一步总结了滇东南地区卡林型金矿成矿规律和成矿模式。8、以成矿系列理论、区域成矿学、成矿预测学作为指导,对该区金矿进行了有针对性的预测研究。并将研究成果重点应用在曼龙沟金矿深边部及外围新区的地质找矿和工程验证工作中;对个旧矿区外围和邱北某金矿深部进行成矿靶区预测,提出在滇黔桂菱块体内除右江裂谷外金等亲铁元素仍然有其他上升通道,因此,在滇东南乃至滇黔桂“金三角”地区具有找寻大型、超大型原生金矿的良好前景。更多还原

【Abstract】 Southeast Yunnan province is a part of Dian-Qian-Gui gold-triangle, one of the famous concentration area of carlin-type gold deposits,and presently the systematic research is still insufficient for it.Guided by theory of plate tectonics,regional metallogenics,geochemistry, metallogenic prognosis,prospecting systematic engineering,based on more than ten years of gold-prospecting practice in Southeastern Yunnan area,the author has collected a large number of geological and geochemical data,analyzed different sub-types of the carlin-type gold deposits,and pay attention to the temporal and spatial distribution of gold and tin-tungsten,copper lead,zinc and silver,antimony arsenic mercury(Ba).Furthermore,took the mineralization,metallogenic law, forming within this area as the main line,the author has conducted systematic studies about its geological and geochemical characteristics, metallogenesis,metallogenesis law and metallogenic prognosis.The main achievements and cognitions are as follows:1.Combined with its existing studies,a redefinition of Carlin-type gold deposits is put forward that is(ultra) fine,disseminated, meso-epithermal gold deposits with concentrated zoning distribution.2.Regional metallogery geological setting of Dian-Qian-Gui gold-triangle was systematically discussed with geology,geophysics, geochemistry and remote sense data,the existence of Youjiang valley(mantle swell) was also be confirmed,and it was demonstrated that the source material of Carlin-type gold deposits in Dian-Qian-Gui gold-triangle is mainly relative to the basic igneous rock and volcaniclastic turbidite deposition which accompanied with the Emei mantle plume activity happened nearby the rift valley and regional discordogenic fault.The regional structure movement and acidity and the basic magmatic activity accompanying were the most important heat source.3.It is demonstrated that the formation and evolution of Nanpanjiang basin is the result of the differential subsidence on the weak district caused by the effusion and horizontal stretching of basalt which originated from the collision of Indian,Eurasian and Pacific plates and then the mantle thriving.It is pointed out that,from the regional geochemistry standpoint,the Youjiang Rift activity begins as early as Cambrian Period at least,and splits gradually form western Guangxi to southeastern Yunnan and southwestern Guizhou.4.A brief introduction about the geological characteristics of carlin-type gold deposit in Southeast Yunnan province is given in the paper.On the basis of its yielding features,host rocks etc.,the Karlin gold ore in southeast Yunnan region could be divided into fine clastic rock-impure carbonatite type,unconformity type,basic rock type and red clay type.Discussed the relationship between Carlin-type gold deposits and gold-bearing construction,magmatic rocks,tectonic,and took the typical gold deposits in this studying area for example,the author presented the geochemical characteristic of the major elements,trace elements,REE,fluid inclusion,isotopes and pyrite single mineral and so on.5.As for the mineralization of Carlin-type gold deposit in Southeastern Yunnan province,it is indicated that crust-mantle inhomogeneity and their interactions→pre-metallogenesis→metallogenesis→post-metallogenesis is a series of natural "Beneficiation" Process and they contacted and promoted with each other. "pre-metallogenesis" concept,the possibility and its implications for mineralization of epithermal-mesothermal ore deposits(such as carlin-type gold deposit etc.) were put forward in the paper.Furthermore, from the geochemical point of view,the author discussed the mechanism of ore-forming transfer and sedimentation.6.Using the theory of metallogenic series,the author discussed the space-time relationship between gold deposit and tungsten,tin,copper, lead,zinc,silver,antimony,arsenic,mercury and other minerals,and put forward there are some major metallogenic series combination in Southeast Yunnan including:(1) the pre-metallogenesis series related to the evolution of northern Vietnam oldland and Nanpanjiang basin;(2) the epithermal-mesothermal minerogentic series related to the Emei mantle column activity;(3) the superimpositiom and transformation minerogentic series related to the Yanshanian granitic magma activity and regional tectonic movement.7.As for the genesis of Carlin-type gold deposit in Southeastern Yunnan,three conclusion are summarized:(1) Crust-mantle inhomogeneity and distribution and redividsion of the elements from original evolution to present are the basic factors of special distribution difference of different ore(2) Pre-metallogenesis is the key factor of the unconformity type gold deposit mainly forming along the Caledonian unconformity surface;(3) Driving heating power came from the northward thrust overriding of Vietnam oldland and strike-slip of a few macroplate,and associated with fault-fold zone,cut-layer fracture structure and the intensive tension zone formed by magmatic intrusion and shrinkage at the external magmatic-body are determinate for the formation of Carlin-type gold deposit and other endogenetic deposit in Dian-Qian-Gui gold-triangle even in southeastern Yunnan province.What’s more,the author formerly summed up the metallogenic laws and metallogenic model of Carlin-type gold deposit in Southeastern Yunnan region.8.As for the gold prospect of the region,guided by theory of metallogenic series,regional metallogenics,metallogenic prognosis,the author made some pertinence investigation,and then focus on the application of research results at geology prospecting and engineering approval in deep ditch and external edge of Manlonggou gold deposit.At the same time,The author predicted the ore-forming targets at the outskirts of Gejiu deposit and deep part of one gold deposit in Qiubei, and put forward that in addition to Youjiang rift,there are still have others ascending passageway for the gold and other siderophile elements in Dian-Qian-Gui gold-triangle.Therefore,it is good prospect to look for large,superlarge primary gold deposit in southeastern Yunnan even in Dian-Qian-Gui gold-triangle area.更多还原