3D geometry and relative chronology of footwall mineralization in the Sudbury mining camp

萨德伯里采矿营地下盘矿化的 3D 几何形状和相对年代学

• 批准号: 471262-2014
• 负责人: Lafrance, Bruno
• 金额: $ 1.7万
• 依托单位: Laurentian University of Sudbury
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=577659
• 关键词: 3D; geometry; relative; chronology; footwall

Significant mineralization is present in older footwall rocks surrounding the Sudbury Igneous Complex in Sudbury. The Sudbury Igneous Complex represents a three kilometer thick impact melt sheet that formed when an extraterrestrial bolide hit the surface of our planet 1850 million years ago. During cooling of the impact melt sheet, sulphide metal droplets segregated from the cooling magma and settled to the bottom of the melt sheet where copper-, platinum-, and palladium-rich sulphide melts were injected in the footwall rocks and crystallized as thick massive sulphide veins. Fluids exsolved from the cooling sulphide melts mixed with hot groundwater heated by the cooling Sudbury Igneous Complex. These fluids dissolved some of the metals and redistributed them to form low-sulphide, high-platinum-palladium mineralized zones. The main goal of the project is to construct a 3D model of footwall mineralization by characterizing the orientation of the massive sulphide veins, their spatial distribution and geometry, and their relative chronology with respect to the formation of the low-sulphide high-platinum-palladium mineralized zones. The model will be used by mineral exploration companies operating in Sudbury and searching for new footwall deposits. The Broken Hammer deposit has been chosen as the target site for the project. The deposit is located deep into the footwall rocks, some 1.3 km north of the Sudbury Igneous Complex. As the Broken Hammer deposit will be completely mined out from start to finish within one year, it offers a unique opportunity to completely characterize a footwall deposit from top to bottom, to map and study the spatial and chronological relationships between the massive sulphide veins and low-sulphide mineralization, and to better understand how footwall deposits form.

在萨德伯里的萨德伯里火成岩杂岩周围的较老的下盘岩石中存在显著的矿化。萨德伯里火成岩复合体代表了一个三公里厚的撞击融化板，它是在一亿五千万年前，一个外星的火流星撞击地球表面时形成的。在撞击熔体冷却的过程中，硫化物金属液滴从冷却的岩浆中分离出来，沉降到熔体底部，在那里富含铜、铂和钯的硫化物熔体被注入下盘岩石中，并结晶成厚厚的块状硫化物脉。从冷却的硫化物熔体中溶解出来的液体与被冷却的萨德伯里火成岩复合体加热的热地下水混合在一起。这些流体溶解了一些金属，并将它们重新分布，形成低硫化物、高铂钯矿化带。该项目的主要目标是通过表征块状硫化物脉体的走向、空间分布和几何形状以及与低硫化物高铂钯矿化带形成的相对年代学，建立下盘矿化的三维模型。该模型将被萨德伯里的矿产勘探公司用于寻找新的下盘矿床。Broken Hammer矿床已被选为该项目的目标地点。该矿床位于萨德伯里火成岩复合体北部约1.3公里处的下盘岩石深处。由于破碎锤矿床将在一年内全部开采完，因此它提供了一个独特的机会，可以从上到下完整地描述下盘矿床，绘制和研究块状硫化物脉体与低硫化物矿化之间的空间和时间关系，并更好地了解下盘矿床的形成方式。