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    Geologist: Professional Reducer-of-Uncertainty?

    Sometime in ancient history I went to university and studied geology. I then joined the minerals industry and became a “Professional Reducer-of-Uncertainty” (PRU). And I’ve remained a PRU ever since.

    Sure, I’ve had the titles of Geologist, Senior Geologist, and Principal Geologist, even Technical Manager – Geology. These roles have entailed exploration geology, resource definition geology, mining geology, resource evaluation geology, and geological due diligence. But, in reality, the titles and functions have been misleading. More correctly, I should substitute every case of ‘geologist’ with ‘reducer-of-uncertainty’, and ‘geology or geological’ with ‘uncertainty reduction’.

    OK, what’s going on here? Surely I’ve trained and practised as a professional geologist, and that’s what I should be called? Fair point, until I need to answer this question “What is my purpose in the minerals industry?”.


    So here it is:

    The sole purpose of a minerals geologist is to reduce uncertainty.

    Right??, you skeptically say, this all sounds very esoteric and airy-fairy. What possible real-world practical relevance does the statement achieve?

    Bear with me……


    Let’s start by considering Exploration Company Z (EC-Z), on the lookout for a new base metals deposit within, for example, Australia. The starting level of uncertainty is massive – just think about the surface extent of the continent of Australia where, hopefully, our hypothetical deposit is lurking.


    A bit of research by EC-Z into the presence and locations of known base metal deposits, supported by relevant economic geology genetic models, immediately narrows the options, and substantially reduces uncertainty about the as-yet-unknown deposit. Exploration licenses are duly pegged along strike of an historically mined deposit, and geochemical surveys are conducted. The results of the geochem further reduce the uncertainty to a series of anomalies that become the targets for geophysical surveys. The geophysics is successful in reducing uncertainty to a handful of sub-anomalies whose uncertain extents are further reduced by surface mapping. Are you getting the idea yet – about the perpetual process of uncertainty reduction associated with traditional geological evaluations?


    And so we continue with the typical sequence of exploration steps, from broad-spaced drilling of anomalies to closing-up of the drill grid, based on initial results – with all associated processes of geological logging, collar and downhole surveying, and assaying. This relentless process of uncertainty reduction will continue through subsequent stages of feasibility studies (resource evaluation), mining production (ore definition and delivery of ore to the processing plant), and finally reconciliation.

    But wait! Do these processes all automatically lead to uncertainty reduction? Yes, probably, but not always as effectively as they should. A poorly-designed drill programme, with inappropriate geological logging coding, substandard sample preparation and assaying, absence of sample QAQC, and ad hoc data management may lead to some uncertainty reduction, but not to the extent possible, and could actually have introduced further uncertainties (e.g. assays assigned to the wrong samples). In this case the “geologists” have failed to deliver the best-possible reduction-of-uncertainty per dollar spent by MC-Z and, in doing so, have not properly executed their obligations as PRUs.


    In fact, failure to adequately reduce uncertainty may potentially lead to sub-optimal exploitation of the resources, the incurring of substantial additional costs or financial losses, or even the complete failure of the mining project and associated businesses.


    So, much as I’m proud to stand behind my tag of “geologist”, and will vigorously defend the importance of geological understanding in undertaking my responsibilities, I am much more likely to achieve my obligations within the minerals industry if I never lose sight of the fact that I am primarily a Professional-Reducer-of-Uncertainty. A good understanding of the geological characteristics of a deposit and their controls on the mineralization are only part of the package required to make me an effective PRU.

    So, what is your take-away from this?


    For starters, at critical junctures, such as the end of a drilling programme, simply ask yourself and your team, “to the extent possible under our budgetary and time constraints, have our activities effectively reduced the uncertainties about our deposit, and what can we do next to improve?” And, “have we objectively and clearly conveyed to management our assessment of what the residual uncertainties might be (hint: resource classification is not sufficient), and the options for optimizing further reductions?” At minimum, asking such questions should contribute to sharpening your team’s skills through critical self-assessment and consequent continuous improvement.

    Hopefully this post has stimulated more than mild bemusement and, subject to finding an elusive gap in my PRU work, I’ll aim to extend the concept a tad further at a later date.

    Chris Arnold

    Chris Arnold

    Principal Geologist

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