How 'orogenic' is orogenic gold? Clues from the Scottish Grampian Terrane

苏格兰格拉姆宾地体是进行详细研究的理想之地：这里的地质学相对来说是众所周知的，而且通常很容易到达。已知有几种贵金属赋存状态，但它们与岩浆和变形事件的成因关系尚不清楚。金以碎屑金和石英脉的形式广泛存在。到目前为止，这些脉系中只有一个(廷德鲁姆附近的科诺尼什)已被开发用于生产，而该地区其余地区的研究仍然严重不足。尽管在苏格兰发现了Cononish、Cavanacaw和Curraghinalt，但苏格兰重大金矿的潜力仍然被低估。复杂造山带的矿化研究需要结合构造、地球化学和地球物理方法的数据。矿石和矿化研究小组(OMG：https://www.facebook.com/OMGLeeds；Twitter@OMGLeeds)涵盖了这些分支学科，包括OMG开发的一种利用金的微量化学来区分造山热液金和岩浆热液金的方法。与持有勘探许可证的公司建立了良好的关系，使其能够获得油田区域、地质和地球物理数据和样本，以及以前的勘探活动结果。作为NERC DTP的学生，您可以进入同位素实验室(例如格拉斯哥的SUERC)。OMG之前的工作提供了重要的背景和支持，包括正在进行的苏格兰、北爱尔兰、爱尔兰和纽芬兰加里多尼亚地区的黄金博士研究。你将专注于阿伯费尔迪-克里夫地区。矿脉矿化的新发现表明，该地区内的矿物学比之前估计的更为复杂。附近的侵入体表明，一些矿化可能与岩浆作用有关。该项目结合了强有力的构造理解、金粒子矿物学和微量化学以及放射性测年。结构工作由行业合作者获得的新的地磁数据支持。你将有机会进行更具区域性的研究，将格兰宾构造演化与碎屑金的成分调查结合起来，以阐明区域成矿作用。主要目标是：1.侵入体和脉体的特征，包括它们与断层框架的关系；2.矿化和侵入体的稳定同位素和地质年代学研究；3.地球物理研究(磁学调查)；以及4.碎屑金的成分研究。预期的结果将是矿床的成因模式，解决i)构造演化、ii)岩浆活动和iii)成矿年龄之间的联系。重点将特别放在区分“造山”和岩浆特征上，以及这些矿床是否可能存在多个与造山和岩浆系统重叠的金矿化事件。一个可证实的多期矿床演化将对全球造山带金矿成因模式的争论做出重要贡献。

The Scottish Grampian Terrane is ideal for a detailed study: the geology is relatively well known and access generally easy. Several precious metal occurrences are known, but their genetic relationship to magmatic and deformation events is unclear. Gold is widespread both as detrital gold and in quartz veins. To date, only one of these vein systems (Cononish near Tyndrum) has been developed towards production, whilst the rest of the area remains severely under-researched. The potential of significant gold mineralisation in Scotland is generally still under-appreciated despite the discovery of Cononish, and of Cavanacaw and Curraghinalt in the Grampian of Northern Ireland.Studies of mineralisation in complex orogenic belts requires a holistic approach combining data from structural, geochemical and geophysical approaches. The Ores and Mineralisation Research Group (OMG: https://www.facebook.com/OMGLeeds; Twitter @OMGLeeds) covers these subdisciplines, including a method, developed at OMG, of using gold microchemistry to discriminate orogenic from magmatic hydrothermal gold. Excellent relationships with companies holding exploration licences provides access to field areas, geological and geophysical data and samples, and previous exploration campaign results. As a NERC DTP student, you have access to isotope laboratories (e.g. SUERC in Glasgow). Previous work at OMG provides crucial background and support, including ongoing PhD studies of gold in the Caledonian terranes of Scotland, Northern Ireland, Ireland, and Newfoundland.You will focus on Aberfeldy - Crieff areas. New discoveries of vein mineralisation point to a more complex mineralogy within the area than previously appreciated. Nearby intrusive bodies suggest that some of the mineralisation may be linked to magmatism. The project combines a robust structural understanding, gold particle mineralogy and microchemistry, and radiometric dating. Structural work is supported by new ground magnetic data acquired by the industry collaborator. You will have an opportunity to pursue a more regional study combining Grampian tectonic evolution with a compositional survey of detrital gold to illuminate regional metallogeny. The main objectives are:1. Characterisation of intrusives and veins, including their relationships to the fault framework;2. Stable isotope and geochronological studies of mineralisation and intrusives;3. Geophysical studies (magnetic surveys); and4. Compositional studies of detrital gold.The expected result will be a genetic model for the deposits, addressing the linkage between i) the structural evolution; ii) magmatic activity; and iii) age of mineralisation. Special focus will be on distinguishing between 'orogenic' and magmatic signatures, and whether the deposits could host several gold mineralisation events overlapping both orogenic and magmatic systems. A demonstratable multi-phase deposit evolution will be an important contribution to the global debate of gold deposit genetic models in orogenic belts.