Mineral exploration is the primary means to define new mineral resources. Following the end of World War II, there was a global economic boom which required the identification and mining of vast numbers of new deposits in order to provide the needed raw materials to sustain the demand. By and large, shallow easy-to-define orebodies were recognized first and developed. In the past 20 years, the discovery performance across virtually all mineral sectors has fallen, resulting in growing concern that if unchecked, there could be shortfalls in a number of commodities within the next 20 years. The collective sense is that there are more deposits to be found, but these are expected to be at greater depths than those that have been typical targets in the past.
To operate in this environment, new approaches for identifying deposits are required and the concept of a mineral systems approach, first suggested 20 years ago, has emerged as a powerful means going forward to build strategies and capabilities. In terms of geophysical exploration, the major change that will be required is a shift from a focus almost entirely on direct targeting with geophysical surveys of deposits, to a staged process where geophysical approaches are used initially to help define the pathways in the earth that carried the mineralizing solutions, which formed the target deposit. These pathways would provide a much larger target and if detected and mapped, should allow explorers to follow the pathway to the location of potential deposits.
This task is different from most geophysical studies, where the focus has typically been on improving the direct targeting capabilities and not the larger scale mapping problem that a mineral systems approach requires. A review of the current state-of-play for a number of major deposit styles shows how geophysical data are being used at present to explore for the larger scale mapping problem. The assessment overall is encouraging but major challenges remain outside of the technical issues of defining a mineral systems strategy that relate primarily to human resources and the commercial environment. With regard to the human resources issue, are there going to be a sufficient number of the right people to develop and implement the required programs? Universities play a critical role in producing new geoscientists but the industry then must take responsibility to train and mentor these people to become functioning professionals. In the commercial environment, at present there is little interest for long-term, strategic programs, either in terms of the needed fiscal support or commitment to undertake the implementation of outcomes. Although governments likely have a greater sense of urgency with regard to this problem, it may be difficult to unilaterally and successfully deal with this complex issue.