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

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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.