Controls on the high-grade gold-cobalt mineralisation at Rajapalot, Finland

芬兰拉贾帕洛特高品位金钴矿化控制

• 批准号: 2743343
• 金额: --
• 依托单位: University of Leeds
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2743343
• 关键词: Controls; grade; gold; cobalt; mineralisation

Cobalt is one of the crucial metals needed for the energy transition as cobalt is found in batteries in e.g. electric vehicles. Gold, in turn, remains a key economic commodity but it is also an important metal in non-corrosive electronic components. The Rajapalot area in Finnish Lapland hosts several high-grade Au-Co prospects with an inferred resource estimate of 887 koz of gold and c. 4800 tonnes of cobalt, based on extensive drilling.The Au-Co mineralisation occurred in two phases. The earlier, Co-only mineralisation is likely to be syngenetic; whilst the latter Au-Co event is structurally controlled with hydrothermal fluids circulated through extensive fracture systems. For the gold, the grade control is only partially understood, and the controls on the high cobalt grades in the Au-Co phase are unresolved. Previous studies, however, imply different processes for the enrichment of the two elements. The grade controls of Au and Co need to be constrained further with a detailed mineralogical, trace element, and textural study. The main aim, therefore, is to investigate what controls the precipitation of Au and Co. There is also potential to address wider scientific questions on the partitioning of Co and various trace elements into sulphides in a hydrothermal system. In particular, the study provides an opportunity to study how trace metal partitioning and Co deposition may be controlled by chemical and physical processes during fracturing and fluid flow. Establishing zoning in sulphides is needed to understand element partitioning and possible fluctuation in the depositional conditions; a detailed paragenetic analysis is also needed to investigate the number and character of fluid pulses/generations that were involved in the mineralisation. Therefore, your main tools will be the Scanning Electron Microscope (SEM) for textural and paragenetic studies; and Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) with a Time-of-Flight capability for trace element mapping in sulphides. Additional data and information can be gained to aid interpretation of the textural and element data: e.g., dating the Au-Co mineralisation may help in understanding the geological context of the mineralisation; or using Leapfrog 3D modelling to understand the spatial context of the mineralisation. You may also have an opportunity for a more regional study, comparing gold alloy compositions and mineral inclusions in gold particles from the deposits with those from placer, using LA-ICP-MS, SEM/BSE and Electron Microprobe Analyser EMPA.

钴是能源转型所需的关键金属之一，因为钴存在于电动汽车等电池中。反过来，黄金仍然是一种关键的经济商品，但它也是一种重要的非腐蚀性电子元件金属。芬兰拉普兰的Rajapalot地区拥有几个高品位的Au-Co远景区，根据广泛的钻探，推断资源估计为887克黄金和约4800吨钴。金钴矿化分两期进行。较早的纯钴矿化可能是同生的；而后者则受热液流体在广泛裂缝系统中循环的构造控制。对于金，品位控制仅部分了解，而Au-Co相中高钴品位的控制尚未解决。然而，以往的研究表明，这两种元素的富集过程不同。Au和Co的品位控制需要通过详细的矿物学、微量元素和结构研究进一步加以限制。因此，主要目的是研究是什么控制了Au和Co的沉淀。也有可能解决更广泛的科学问题，即Co和各种微量元素在热液系统中分解成硫化物。特别是，该研究为研究压裂和流体流动过程中化学和物理过程如何控制微量金属分配和Co沉积提供了机会。需要建立硫化物的分带，以了解元素分配和沉积条件可能的波动；还需要进行详细的共生分析，以研究参与矿化的流体脉冲/世代的数量和特征。因此，您的主要工具将是用于纹理和共生研究的扫描电子显微镜（SEM）；激光烧蚀电感耦合等离子体质谱（LA-ICP-MS）具有飞行时间能力，用于硫化物中痕量元素的定位。可以获得额外的数据和信息来帮助解释结构和元素数据：例如，确定Au-Co矿化的年代可能有助于理解矿化的地质背景；或者使用Leapfrog 3D建模来了解矿化的空间背景。您也可能有机会进行更区域性的研究，使用LA-ICP-MS， SEM/BSE和电子探针分析仪EMPA，比较来自矿床和砂矿的金颗粒中的金合金成分和矿物包裹体。