Grant: Alliance Grants

Most large and easily accessible mineral deposits have been found and exploited. To continue to supply critical mineral resources central to global industries, mineral exploration must move to deposits that are deeper or smaller, and therefore are more challenging to identify and characterize using geophysical methods. Geophysical inversion is an imaging approach that provides information about the subsurface physical properties of the Earth (density, conductivity, etc.) based on measurements of physical fields (gravity, electromagnetic, etc.). That physical property information can be interpreted to identify and characterize the mineral content inside the Earth. To do this successfully, there must be a tight integration between the geophysical and geological data typically collected for mineral exploration. This research will look at novel state-of-the-art geophysical inversion methods and develop approaches for such tight integration. Specifically, we will research surface-geometry inversion methods, which parameterize the Earth in terms of surfaces between different rock units. This parameterization is more consistent with geologists' understandings of the Earth, and has high potential to allow the tight integration of geophysical and geological information that we seek. Surface-geometry inversion methods are becoming more common but little work has thoroughly assessed approaches for using these methods to integrate geophysical and geological information; that will be the primary objective of this research project. A secondary objective is to further improve current computational aspects of surface-geometry inversion methods by researching the mathematical optimization approaches that are required to perform the inversions. This work will develop sophisticated modelling methods and related software that can be immediately adopted by mineral exploration companies in Canada, and thereby strengthen Canada's position as a global supplier for critical minerals.