The Summit is a major initiative by the Australian Academy of Science to create a suitable platform for local academia, service providers, government and industry to work collaboratively together to enhance Australia’s discovery rate through developing better knowledge and methods for exploring under deep cover. A summary of the Summit’s proceedings and proposed initiatives will be reported back to the Federal Government and other relevant stakeholders for action. For more information on the UNCOVER Initiative go to http://www.science.org.au/publications/searching-deep-earth-vision-exploration-geoscience-australia
My presentation focused on the business case for exploring under cover in Australia.
Key observations were that:
- Exploration expenditures in Australia peaked in 2012 and have fallen by half in the last 2 years. But even so, the level of spending is still twice that of a decade ago. However all of the growth was in bulk minerals
- On average 10 discoveries are made each year in Australia. Most of these are small in size and value
- On average over the last decade $1.12 worth of value was created per $1 dollar spent on exploration in Australia. This is significantly higher than most other regions in the World – highlighting the relative attractiveness of Australia.
- Three-quarters of the value created was associated with Tier 1 and 2 discoveries – which is why companies should focus on them.
- The average depth of discovery in Australia is now 79 metres – which is less than that in Canada (129 metres), Western Europe (152 metres) and the United states (224 metres)
- Notwithstanding the fact that you need to drill in order to discover, the drilling activity is incredibly inefficient. On average it took 20 million metres / 250,000 holes to find a giant deposit! We need to be smarter where we drill!
- Based on an assessment of 1.4 Million holes drilled in Western Australia since 1977, 50% of the holes were less than 34 metres deep. Only 10% of the holes went beyond 96 metres and less than 1% of the holes were deeper than 300 metres. Plotting these holes up on a map shows that the Yilgarn Province is wide-open for fresh targets at depth.
- A study of gold and base metal discoveries in the Western World since 1950 shows that the top 25 metres is now getting mature – with the size and quality of discoveries made being smaller than deposits under deeper cover. Great opportunities exist to find significantly more deposits below 50 metres.
- The challenge is that below 50 metres of cover geochemistry becomes a less effective exploration tool. The same applies to geophysics below 200 metres.
In summary, my analysis shows that great opportunities to find high quality gold and base metal deposit under moderate-to-deep cover in Australia. To discover these will obviously require the development of new / better search tools. This was the focus of the rest of the Conference.