【作者】 游先军；

【导师】 戴塔根；

【作者基本信息】 中南大学 ， 矿产普查与勘探， 2010， 博士

【摘要】 湘西下寒武统黑色岩系中的Ni、Mo、V矿床,80年代中晚期开始断续开发利用,90年代末达到高潮。然而研究工作相对滞后,虽然有不少学者、专家教授从多个方面进行专题研究探讨,取得了不少研究成果,但对区内Ni、Mo、V矿床的研究亟待加强,特别是对钒矿研究更显薄弱。选题研究湘西下寒武统中的镍钼钒矿床,是在前人已有研究成果的基础上,充分利用了自2005年9月1日实施本区深部找矿勘查工程以来所取得的勘查成果,着眼于矿床的成矿地质背景、黑色岩系的主要岩石类型、岩(矿)石地球化学特征、矿床地质特征、成矿元素的富集组合与成矿作用、矿床成因以及矿床开发利用前景等多方面进行较深入系统的研究工作。本次研究工作以岩石地球化学和矿床地球化学理论为指导；以前人对华南及本区黑色岩系的研究成果为依托；以区内深部找矿和矿业开发资料为基础。通过对已知勘查区和矿业开发区野外考察、采样检测、室内综合研究等手段,查明区内下寒武统黑色岩系中镍钼钒矿及其围岩的区域地质背景、成岩成矿地质条件、矿床地质特征,探讨矿床控矿因素、成矿规律、成矿热动力条件以及矿床的成因模式等,并简单研究了矿床的开采技术条件、选冶技术性能和开发利用前景。湘西下寒武统黑色岩系,是我国南方黑色岩系的重要组成部分,经历了晚震旦世—早寒武世早期扬子陆块由拉张向热沉降转换,以及早寒武世早期—早奥陶世被动大陆边缘的演化。形成了一套碳酸盐台地边缘沉积和斜坡沉积的碳酸盐岩、碎屑岩。相应的矿床与华南下寒武统黑色岩系中的层状矿床可以类比。区内花垣—慈利深大断裂是区内重要控岩控矿构造,与区内地层分布、矿床形成关系极为密切。含矿岩系(黑色岩系),不是以炭质页岩为主,而是一套碳酸盐岩、硅质岩、磷块岩、碎屑岩组合。含钒岩系主要为炭质磷质硅质岩、炭质硅质白云岩、硅质磷块岩、硅质粘土岩等；含镍、钼岩系主要为硅化—碳酸盐化磷质粉砂岩、炭质磷质粉砂岩、硅化碳酸盐化磷块岩、硅质磷块岩、重晶石化砂砾屑磷块岩、炭质白云岩等。岩(矿)石元素地球化学特征的研究表明,镍钼矿床和钒矿床形成环境和成矿作用(包括成矿物质来源)均有较大差别。根据矿床中的微量元素、稀土元素、分散元素、贵金属元素等含量变化、组合特征以及流体包裹体特征等认为：钒矿层形成于正常浅海陆缘海盆地环境,成矿作用主要为生物化学成矿作用,成矿物质来源为多源；镍、钼矿形成于较特殊的陆缘深海槽环境,成矿作用以海相热水成矿作用为主,海底火山喷流作用为成矿提供了丰富的矿质。含Ni、Mo、V黑色岩系中,伴生元素具有明显特定的组合。V、P、C, Yb、Ba含量均很高,是本区域主要异常元素。钒矿层中伴生元素很低,不具备综合利用价值。镍钼矿层中伴生元素组合较为复杂,伴生V、Cu、Zn,富含Pt、Pd、Os,分散元素Se、Cd具明显异常含量。主量元素在含矿黑色岩系中除CaO略高外,与大陆沉积壳层组份平均含量基本一致。元素含量变化具有如下规律性：Yb在地层和矿体中含量均很高,是地壳元素丰度的数十万倍；Ba的含量在地层和钒矿体中比镍钼矿体高出数十倍；钒矿体中Ni、Mo含量低,且不含其它伴生元素(Ba, Yb除外)；镍钼矿体中富含贵金属元素,Mo与贵金属(Pt、Pd、Os)具明显正相关,Ni与贵金属无相关性。Ni、Mo、V的赋存状态研究表明：镍钼钒赋存规律明显。钒主要以离子吸附态、类质同象等赋存于粘土矿物中,在炭和有机质中含量极少,在黄铁矿、辉钼矿中含钒,但以何种形式存在,有待于进一步研究,目前很难确定区内有含钒的独立矿物。镍的独立矿物较多,主要是硫化物和硫砷化物,钼的独立矿物主要是辉钼矿。本次研究认为：Ni、Mo应有相当部分不是以独立矿物存在,仅是笼统的解释为“硫炭钼矿”比较勉强。钼的唯一独立矿物辉钼矿,在镜下观察为典型次生(后生)矿物,是在成岩之后形成的；大量的含镍主要矿物针镍矿也是典型的次生矿物,是由含镍黄铁矿分解而成。研究区镍钼钒矿体属顺层整合矿体。钒矿层与镍钼矿层顺层整合产出,矿区Ni、Mo矿床和V矿床,剖面上可以对比,具沉积型矿床的基本特征。成矿作用以生物化学沉积作用为主,成矿物质来源具多源型。海底喷流和海相热水作用,为区内镍钼钒矿床的形成提供了大量的成矿物质。致使区内Ni、Mo矿床的形成表现出两套成矿系统和多种成矿作用特征。无论是湘西、贵州遵义,还是浙西—开化—诸暨,凡是下寒武统黑色岩系中镍钼矿床(含贵金属矿化)的地区,其下伏地层必然是上震旦统灯影组白云岩类。一旦该层位岩性沿走向相变为热水沉积的上震旦统留茶坡组硅岩,其上为下寒武统黑色岩系的沉积型钒矿层,而镍钼矿富集层位则消失。镍钼钒矿床的开发利用研究结果表明：本类型矿床勘探难度小、开采技术条件简单、选冶加工技术成熟,能够满足“绿色矿山”建设、生产的各项要求,具有良好可开发利用前景。更多还原

【Abstract】 Ni, Mo, V deposits in Lower Cambrian black rock series Xiangxi (Western Hunan) were to be of intermittent development and utilization in the mid-late-80s and to be achieved success in the late nineties. However, research is lagging behind, although there are many scholars, experts and professors who studied the thematic on several aspects and achieved a lot of research results, the study of Ni, Mo, V deposits is still need to be strengthened, especially for vanadium ore research in this area.Research topics of nickel-molybdenum-vanadium deposits in the Lower Cambrian of Xiangxi is based on the research results of the predecessors, fully utilized the deep mineral exploration results achieved by the exploration teams since September 1,2005. From the ore-forming geological background, the main rock types of black shales, rock (ore) geochemical features, deposit geological characteristics, combined with the enrichment of ore-forming elements of mineralization, ore genesis, as well as the prospects for development and utilization of deposit, etc. It makes my study work more in-depth and systematic.This research work is guided by the rock geochemistry and ore geochemical theory; based on the information of deep exploration and mining development in the area; relied on the research results of black shales of the predecessors in South China. Through the field inspection of the known exploration area and the mining zone, sampling inspection, indoor comprehensive research and other means, identified the regional geological background of Ni-Mo-V ore and the Lower Cambrian black rock series, diagenetic ore-forming geological conditions, deposit geological characteristics. Explored the ore-controlling factors, ore-forming law, ore-thermodynamic conditions, ore deposit origin pattern and so on. And studied simply the ore deposit mining engineering factor, dressing and smelting technology and prospects for development and utilization.Lower Cambrian black shales in Western Hunan are an important part of black shales in South China. In the late Sinian-Early Cambrian, Yangzi continental block converted from tensile to thermal subsidence, as well as evolved passive continental margin in the early Cambrian-Early Ordovician. Had the formation of a carbonate platform margin deposits and slope deposits of carbonate, clastic rocks. The appropriate deposit with the layered deposits of the Lower Cambrian black rock series in South China may be assimilated. Huayuan-Cili is an important regional deep fault, which controlled rock-ore structure, stratigraphic distribution, and has very close ties with the formation of ore-deposits.Ore-bearing rocks (black shales), is not in carbonaceous shale-based, but a set of carbonate, chert, phosphate rock, clastic rock combination. Vanadium-containing rocks are mainly carbonaceous cherts phosphorus, carbonaceous siliceous dolomite and siliceous phosphate rock, siliceous clay, rocks, etc. Ni.Mo-Containing rocks are mainly carbonaceous silicified rocks, carbonaceous phosphorus siltstone, carbonaceous silicified phosphorite, silicious carbonate-based phosphate rock, silicon phosphate rock, heavy goods, barite gravel dust phosphate rock, carbonaceous dolomite and so on.The studies of rock (ore) geochemical characteristics have shown that Ni-Mo-V deposit are quite different in the ore-environment and ore mineralization, including ore-material sources. According to the content changes of trace elements, rare earth elements, dispersed elements, noble metals, as well as portfolio characteristics and the characteristics of fluid inclusions in deposits, it could be that:V-seam formed in a normal shallow marginal sea basin setting, mineralized process is mainly biochemical mineralization, ore sources for multi-source; Nickel, molybdenum formed in the more specific marginal trough environment, mineralized process is mainly marine hydrothermal mineralization, and submarine volcanic effusion to provides a rich minerals.In Ni, Mo, V-Containing black rock series, the associated elements have obvious specific combination. V, P, C, Yb, Ba are the main anomalous elements with very high contents in the region. The associated element in Vanadium ore bed is very low, and do not have comprehensive value. The associated elements in Ni-Mo ore bed are of more complex combination: associated V, Cu, Zn, rich in Pt, Pd, Os, and dispersed elements Se, Cd with high content of a markedly anomalies. Major Elements in the ore-bearing black shales, are basically the same average concentration with Continental sedimentary shell components, exception to CaO with slightly higher.Changes in element content have the following law:Yb content in the formation and content of ore bodies is as hundreds of thousands of times as the crust elements abundance; Ba,V content in the ore body formation are the number of times higher than that in the Ni-Mo ore bodies; Vanadium ore body is lower Ni, Mo content, and without other associated elements (Ba, Yb, except); Ni-Mo ore bodies is rich in precious metal elements, Mo and precious metals (Pt, Pd, Os) with significant positive correlation, but Ni and precious metals with no correlation.Ni, Mo, V studies have shown that the occurrence condition:Vanadium mainly occurs in the clay minerals,as ions adsorbed, isomorphism, etc., In the carbon and organic matter, its content is extremely low. It is necessary for us to pay attention to that the pyrite and molybdenite contain vanadium. But in what form, need to be further studied. Of course, it is difficult to determine the independent vanadium minerals in the region. More independent nickel minerals are mainly arsenic sulfide and sulfur, Molybdenum independent minerals is mainly molybdenite. This study suggests that:a considerable part of Ni, Mo should not existed in the independent minerals. Is only a general explanation of the "sulfur-carbon molybdenum" more reluctantly. The only independent molybdenum mineral molybdenite, which is the typical secondary (epigenetic) minerals in the microscopic observation, formed after diagenesis; A large number of major nickel-bearing mineral-capillose, is also a typical secondary minerals, decomposed by nickel-bearing pyrite.In the study area, nickel-molybdenum-vanadium ore body are bedding integrated with formation. V-seam with the Ni-Mo ore bed can be compared in the profile, with the basic characteristics of sedimentary deposits. Mineralization are mainly biological deposition and ore sources with characteristics of multi-source model. Marine hydrothermal mineralization and submarine volcanic effusion provided a rich ore-materials for the formation of Ni-Mo deposits. That is why the Ni, Mo, V ore deposits display two sets of minerogenesis systems and many kinds of mineralization characteristic in the area.Whether it is in western Hunan, Guizhou and Zunyi, or western Zhejiang-kaihua-Zhuji, any Ni-Mo-bearing deposits (including the precious metals mineralized) zone in the Lower Cambrian black rock series of which underlying strata must be dolomite of the Upper Sinian Dengying group.Once the strata lithology along the strike changed into silicified rocks of the Upper Sinian(Liuchapou group) formed by hot-water sedimentation, Then became sedimentary vanadium ore bed, while the nickel-molybdenum enrichment horizon disappeared.The research results of Ni-Mo-V deposits in Xiangxi(Western Hunan) show that:This type of ore-deposite is easy to do exploration, simple to do dressing and smelting, effective to do mining and production. It is able to meet the requirements for "green mining" construction, and possesses good prospects for development and utilization.更多还原