Geochemistry of shales as vectors to ore deposits : CAMIRO Project 08E04

广泛的经济矿床类型，包括贱金属、金和铀，赋存于含硫化物、碳质页岩或泥岩中，或在空间上与之相关。碳质页岩和泥岩很容易在航空电磁测量中被识别出来，通常被钻探为火山成因块状硫化物(VMS)和沉积喷气(Sedex)矿床的潜在宿主。它们也是造山金、铀、沉积物容矿铜和富含其他金属(如镍、铂族元素)的矿床的重要容矿地。在某些情况下，黑色页岩是金属的还原圈闭；在另一些情况下，它们是成矿事件或潜在金属源岩的重要岩石地球化学标志。然而，碳质页岩在成矿中的作用仍然知之甚少，而且在不同的地质环境下，这些岩石中的矿藏潜力几乎没有得到充分证实的指标。在5家矿业公司(Barrick Gold、HudBay Minerals、Newmont、Teck、Ur Energy)的支持下，加拿大矿业研究组织(CAMIRO)的08E04项目启动了一项与不同矿床类型有关的页岩岩石地球化学研究的新国际计划。该项目的主要目标是：(1)提高目前对古火山沉积盆地和造山带页岩和泥岩中金属富集度的认识；(2)评估碳质沉积物在沉积和埋藏后成矿(如造山带金矿)过程中作为金属源和金属陷阱的作用；(3)开发新的矿物学、地球化学和同位素工具，以区分各种成矿环境中潜在矿化的页岩和未矿化的页岩。5名研究生(3名在加拿大，2名在美国和澳大利亚)将通过贱金属矿床、金矿和铀矿的案例研究为该项目做出贡献。学生将在实地工作、实验室分析、行业互动以及口译和准备研究出版物方面获得经验。在该项目期间开发的勘探技术将通过合作伙伴关系直接转让给矿业公司。

A wide range of economic ore deposit types, including base metals, gold, and uranium, are hosted by or spatially associated with sulphide-bearing, carbonaceous shales or argillites. Carbonaceous shales and argillites are readily identified in airborne electromagnetic surveys and are commonly drilled as potential hosts for volcanogenic massive sulphide (VMS) and sedimentary exhalative (SEDEX) ore deposits. They are also important hosts for orogenic gold, uranium, sediment-hosted copper, and deposits enriched in other metals (e.g., Ni, PGE). In some cases black shales were a reductant trap for metals; in others, they are important lithogeochemical markers of ore-forming events or potential source rocks for metals. However, the role of carbonaceous shales in ore formation remains poorly understood and there are few well-established indicators of ore potential in these rocks in different geological environments. A new international program of research on the lithogeochemistry of shales in relation to different ore deposit types is being initiated with the support of 5 mining companies (Barrick Gold, HudBay Minerals, Newmont, Teck, Ur Energy) as Project 08E04 of the Canadian Mineral Industry Research Organization (CAMIRO). The principal objectives of the project are (i) to improve the current understanding of metal enrichment in shales and argillites in ancient volcanosedimentary basins and in orogenic belts, (ii) to assess the role of carbonaceous sediments as both metal sources and metal traps, during sedimentation and during post-burial metallogenesis (e.g., in orogenic gold deposits), and (iii) to develop new mineralogical, geochemical, and isotopic tools to discriminate between potentially mineralized and unmineralized shales in a variety of ore-forming environments. Five graduate students (3 in Canada, 2 in the U.S. and Australia) will contribute to the project through case studies of base metal deposits, gold deposits, and uranium deposits. Students will gain experience in field work, laboratory analysis, industry interaction, and interpretation and preparation of research publications. Exploration technology developed during the project will be transferred directly to mining companies through the collaborative partnership.