Q&A from the experts: In conversation with Graham Brown

July 26, 2019
Graham Brown, Independent Consulting Geologist

Graham Brown was educated in Glasgow (Strathclyde University), graduating with a BSc in 1980. He gained his MSc at James Cook University, Australia in 1984. He has been a Fellow of the SEG since 1999 and participated in the Colombia as well as the Duke Business Leaders Programs in 2004 and 2007. In 2013 he attained both Chartered Geologist and European Geologist professional status. Graham has 35 years’ experience in the mining and exploration business employed as an independent consultant, chief geologist, senior executive and global leader of a highly successful award-winning discovery team. He has lived and worked on four continents where he has completed more than 100 technical assignments, covering a range of commodities in over 25 countries. He is a past SEG councillor and BGS industry representative and current NHM honorary research fellow. Industry awards, recognition and world-class exploration discoveries credited to his Anglo American team during the last decade include: Los Sulfatos (PDAC), Sakatti (FEM) and being ranked the most successful major base metals explorer (MEG).

Grigor Topev: What were your reasons for choosing geology?

Graham Brown: I was born in 1958 – the same year NASA was created. Exploration and discovery have always been my passion;
new countries, new cultures and new ore deposits!

GT: You have worked in so many countries; which one left the strongest impression on you and why?

GB: A hard choice, but probably Australia, where I spent the first five years of my career. It was a great start to my ‘apprenticeship’ as a geologist and I worked with some of the best mine finders in the business.

GT: You were awarded with the PDAC Thayer Lindsley Award for significant mineral discovery. What discovery was the award for?

GB: I led the team credited with the discovery of the world-class Los Sulfatos Cu-Mo porphyry deposit. The major annual award was presented for the best international mineral discovery. Located 7 km from Los Bronces mine, 45 km NE Santiago, in the high Andes, Chile. Discovered in 2006 as part of a systematic evaluation of the district’s exploration potential. The site posed challenging conditions; high-altitude (>4000 m), rugged terrain, harsh winters, short summer field seasons (4 months) and access to the area was only possible by foot, mule or helicopter. Only after the company’s 10th drill hole were the size and quality of the deposit apparent. The initial inferred resource based on 22 000 m drilling, totals 1200 Mt at 1.46 % Cu and 0.02 % Mo contained an estimated 17.5 Mt of copper. The overall mineralized system may well exceed 4000 Mt at >0.8 % Cu.

GT: You have spent many years as a consultant in Asia, and in some European countries where you continue to work. Can you tell us more about this and share the most challenging and interesting moments from these periods?

GB: I spent 10 years consulting in Asia Pacific and European regions on a number of world-class discovery and evaluation projects. In terms of the most challenging and exciting moments, two examples include the Lihir epithermal Au deposit in Papua New Guinea (PNG), associated with an active geothermal system located on the island. At the time (in the mid-1980s), this was a new deposit type and it was very exciting to be part of the evaluation team.

Also, the Ovacık epithermal Au deposit, which is located in western Turkey. This was a new frontier in exploration and we were finding new, outcropping Au systems that had never been recognized or sampled by modern techniques.

GT: How did you start at Anglo American and what positions did you hold there?

GB: I worked for the Head Office in London for 15 years. During that time, I held three positions: Chief Geologist, Global Head of Exploration, and Global Head of Geosciences.

GT: What is the discovery of the decade, in your opinion?

GB: I am biased but it would have to be Los Sulfatos. We developed an 8-kilometer exploration tunnel using a tunnel boring machine (TBM). This was the first time TBM technology had been used in a near-mine exploration stage project. The most amazing experience was to walk the tunnel, which intersected the core of the mineralized system with Cu grades over the last 3 km of the tunnel averaging >1 % Cu, including 1.6 km at >1.5 % Cu!

GT: Is Mineral Exploration in crisis?

GB: If you look at the return on spending and the number of economic discoveries delivered as an industry, then unfortunately, yes.

GT: What measures should be taken to end the crisis?

GB: Four critical areas govern success: exploration strategy, management, innovation and talent development.

GT: What are the most common mistakes that mining companies make, in terms of exploration?

GB: The discovery of ore bodies is not a mystical art. Discoveries are not tied to how much you spend or not using state-of-theart theories or technologies. Successful discovery is about leadership – both in the field and the boardroom.

GT: Is it true that only a small percentage of junior exploration companies and their discoveries are worthwhile?

GB: This is true for not only junior but also mid-tier and major companies. The time-value of money accounts for 70 % of the cost of exploration. The industry needs to turnover exploration targets more efficiently and effectively, and focus on advancing the quality opportunities.

Exploring for epithermal gold in the Afar depression, Ethiopia and Djibouti

GT: Is there a lack of good-quality deposits? What does it take to find one?

GB: No, successful exploration and finding new ore deposits are people-driven and a team effort. Key success factors include discovery culture, high-quality hunting pack teams, innovative geological thinking, appropriate discovery tools and evaluation technologies, consistent funding, and time to build local knowledge and operating capabilities.

GT: Do you agree that there is a current tendency for companies to reopen old mines that have not been in production for years? Is it less risky to look for deposits where they have already been found rather than explore new locations?

GB: I believe there should be a balance between greenfield and brownfield exploration. Focusing only on known, mature districts which will eventually be depleted actually increases the discovery odds.

A balance of greenfields and brownfields in any exploration portfolio is essential for longterm exploration success. A mix of the two creates a diversified project portfolio with different levels of maturity and risk.

GT: How has mineral exploration changed in the last ten years? What are the advantages and disadvantages of this profession?

GB: The most significant changes would be the importance of maintaining the ‘license to operate’ to ensure continued access to land, resources, and talent. The biggest challenges are the increase in data, computers, HSE reporting bureaucracy, and the reduction in both field skills and rock contact time.

GT: What is a good exploration strategy and why is it important to have one?

GB: You need a balance of risk and reward when selecting the what, where, and how to explore, and to identify the key enablers that will deliver value and provide options for growth. The key drivers in exploration are resource replacement, asset upgrading, discovery track-record and risk mitigation.

Set the right strategic direction and you will reduce risk. Commit to pursuing mineralized districts, aiming at simple, large targets and commit to drilling. Balance greenfields and brownfields, ensure you align your drilling strategy with return on investment (ROI), commit to ‘boots and hammer’, consider joint ventures (JVs), and most of all, be persistent.

GT: Can you give three key points to consider when choosing a drilling contractor?

GB: Safety, experience, and equipment.

GT: Is there anything that drilling contractors commonly lack and which you find important?

GB: Ideally, drilling contractors would combine geophysical and geochemical surveys with their drilling programme. That would improve efficiency and can assist in real-time decision-making.

GT: What has been the most challenging drilling campaign in your career?

GB: As discussed above, the Au deposit on the remote Pacific island of Lihir (part of Papua New Guinea), which is an active geothermal system and required large-diameter PQTTT coring and blow-out preventative equipment.

GT: At what stage of the exploration campaign is it important to have well-defined targets for the drill holes?

GB: Those are needed after you have completed the geological mapping and appropriate geochemical and geophysical surveys and baseline environmental monitoring.

GT: How important is core orientation, and what would you like to see improved in the latest core-orientation technologies and procedures?

GB: Core orientation is critical in the structural interpretation and modelling of ore deposits. This is particularly important at the evaluation stage to improve the geological and structural models, plus resource estimation. I would also like to see core-orientation improvements being linked to a trade-off between real-time visualisation and cost.

GT: Can you tell us the key elements of Exploration Management?

GB: Ownership of the exploration strategy is important, and you need to foster a culture of success, manage the exploration department as a profit centre, establish credibility with senior management and the board, and minimize company distractions.

GT: What do you think is in store for the future of mineral exploration?

GB: Three key challenges lie ahead: improving the declining rate of discovery, reversing the trend of increasing costs and lead time, and maintaining our license to operate. It cannot be over-emphasized that successful discovery is about leadership in the field and the boardroom.