Geophysical tools to explore for mineral and hydrogeological resources

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This proposal describes ongoing projects to develop geophysical tools that will allow people to determine what is hidden below the subsurface by measuring fields on the surface of the earth or down the occasional boreholes that are drilled to investigate the subsurface. One set of tools involve measuring electromagnetic fields where the intent is to look for conductive features such as valuable nickel and copper deposits that could be mined to the benefit of the Canadian economy. These deposits have generally been found where the deposits are shallow, so a tool that can look for deeper deposits is required. The innovation that will enable deeper investigation is to use a transmitter that has three transmitter coils oriented in three different directions, rather than the standard single coil pointing in one direction. Student projects will involve developing this system, testing it and processing and interpreting the data collected. The second set of tools involve measuring small perturbations in the magnetic field of the Earth. In this project, a student will be developing an innovative methodology to create images of the data that have fewer artifacts and look more like the subsurface geology. This will enable people to more easily interpret the source of the perturbations below the subsurface. This will enable a better understanding of the geology and will assist in resource exploration. The third set of tools measures the nuclear magnetic resonance associated with protons in the subsurface. These protons are primarily associated with water, so the tool is used to look for groundwater in arid areas. The innovation in this project is for a student to develop a tool that can be carried by aircraft and find this water quickly and easily. However, the airborne results are low resolution and the airborne tool will likely have a shallow penetration. Nonetheless, the results should enable hydrogeologists to select locations on the ground where higher resolution and deeper penetration investigations can be undertaken. A final innovation is for a student to develop a computer application that will allow practitioners and students to understand the character of the electromagnetic responses that are measured with tools such as those described in the second paragraph above. This will allow people to determine the subsurface conductive feature that is the source of the electromagnetic fields. In this case, the innovation is that the source can be buried below a conductive surface layer and the computations can be undertaken relatively quickly.