Get new articles sent directly to
Earth Explorer is an online source of news, expertise and applied knowledge for resource explorers and earth scientists.
Sponsored by Geosoft.
March 12, 2013
On Tuesday March 26, 2013 the TGDG will host a selection of speakers for a mini-symposium at Hart House on ‘Laterites or Laterwrongs: Making the Pieces Fit’. Speakers include Ravi Anand (CSIRO), Peter Winterbourne (Vale), and Ron Schonewille (Xstrata)...
March 11, 2013
Hailing from industry, government and academia, high profile Australian and internationally-based researchers will join the CET fortnightly to share their experience on a wide variety of geoscience topics.These seminars are FREE and all interested Geologists are welcome to attend...
February 25, 2013Is regulation robbing exploration properties of their worth?
You can’t get chickens if you don’t allow the eggs to develop. Joe Hinzer, president of geological consulting firm Watts, Griffiths and McOuat (WGM), uses this analogy to illustrate how many early-stage exploration projects are being stifled by current mineral valuation regulations before they have a shot at becoming mines...
February 04, 2013
It has been a busy 24 hours as the Association for Mineral Exploration British Columbia (AME BC) kicked off its Mineral Exploration Roundup 2013...
January 29, 2013Where do I meet the geologists of Africa?
Africa is more than 20 per cent of the world’s land area, is home to 15 per cent of human population but still earns its label as the Dark Continent through generating only 2 per cent of the world’s electricity. Where can you find the geologists exploring this sleeping giant with its inevitable future in the resources sector?
January 28, 2013
As exploration programs focus on remote and concealed targets, the ability to recognize large ore-forming systems – from the most distal margins to high-grade cores – becomes increasingly important. Efforts are therefore under way to generate sophisticated “footprint” or “signature” models of high-value deposits.
December 2, 2012
The December 4th Greenland Day, taking place in Perth, will feature industry and geoscience experts from across the globe, discussing Greenland’s burgeoning exploration opportunities and recent research advances...
November 1, 2012
Some of the sector's leading minds will be looking into their crystal balls on November 8th, trying to summon a picture of what the future might hold for exploration and mining in Canada...
September 11, 2012
Brazilian state-run energy giant Petroleo Brasileiro, or Petrobras, said Tuesday that it had started oil production at the Baleia Azul presalt field in the offshore Campos Basin...
September 11, 2012
Barrick Gold CEO Jamie Sokalsky speaks with Carl Quintanilla on CNBC about Barrick's strategy to drive shareholder value...
September 10, 2012
The tie between energy supply, population, and the economy goes back to the hunter-gatherer period...
July 12, 2012
A massive two thirds of Western Australia remains unexplored for minerals and geologists say the territory presents huge potential...
July 12, 2012
Shale and other unconventional resources are being called the biggest game changer in a generation - and as land and other costs escalate, the industry continues to apply lessons gleaned from the early successes...
July 11, 2012
In this exclusive interview with Professor David Thiel, Director at the Centre for Wireless Monitoring and Applications at Griffith University, he discusses how electromagnetic geophysics can help those who are conducting a feasibility study and opens up on the real cost benefits of this technology...
July 11, 2012
Improved security has started to open up new areas for mineral exploration in Latin America....
by Virginia Heffernan on September 11, 2012 expertise
What if you could generate a map that identified not only exploration targets, but also the likelihood of those targets becoming economic deposits? The authors of the cover article for July’s edition of SEG Newsletter say this kind of “radical approach” to exploration is both possible and necessary.
“The decision about where to look is too often based on an informal interpretation of partial information rather than quantitative analysis of all the available data,” say Colin Barnett and Peter Williams, principals of data mining firm BW Mining and authors of A Radical Approach to Exploration: Let the Data Speak for Themselves. “If we are to improve the discovery rate, we need to put more effort into targeting, or deciding where to look.”
The authors say explorers can increase their chances of success several fold by using statistical analysis in known camps with good quality databases. Advances in pattern recognition combined with greater accessibility to government datasets and lower costs for data storage and processing make it possible to not only pinpoint targets, but to determine the expected economic costs and rewards of each target.
That approach had a 50% success rate in finding more gold in the Porcupine camp of northern Ontario. The jury is still out on the duo’s most recent study area, the Eastern Goldfields North (EGN) portion of the Yilgarn craton in Western Australia.
“The favorable ground is almost completely taken in the EGN, so we need to come to suitable arrangements with current license holders,” Barnett said in an e-mail. “But there are targets on land held by most of the major players.”
The EGN covers about 165,000 km2,or a landmass roughly the size of Wisconsin or Uruguay. The area contains a high concentration of known gold deposits, public access to modern data, and less than 10% outcrop, making it a prime candidate for detailed statistical analysis of geological, geochemical and geophysical results.
Barnett and Williams’s analysis may be beyond the grasp of the average geoscientist, but it involves inputting all the layers of primary exploration data, such as magnetics and lithology, as well as the derivatives of that data, into neural networks. After taking into account all the available data for EGN, for example, the authors ended up with more than 250 layers representing a mindboggling 15 Gb of gridded data files.
The statistical approach allows explorers to quantify the relevance of each data set. In the EGN case, biogeochemistry (sampling the leaves of mulga trees) and geological structure (the area’s gold occurrences are commonly associated with major shear zones, secondary faults and hinge areas of antiforms) proved to be the most informative, while magnetic data was the least helpful.
The EGN study generated more than a dozen high priority targets. Some of them are brand new, but most occur in established camps within a few kilometres of operating mines or old workings.
Will this kind of high level statistical analysis revolutionize exploration in known camps and other areas with plentiful data? Or does the cost and expertise required outweigh the benefits of being able to pinpoint targets with a high probability of success?
This article has generated lively discussion on Earth Explorer's Linked In group. Group members pointed out some limits to universal application of a statistical analysis approach, perhaps the biggest hurdle being the need for comprehensive geological, geophysical and geochemical datasets from areas that have already undergone exploration to some degree.
Lyndon Hardy, senior exploration geologist for Abra Mining in Perth, put it best: "Until there is sufficient regional data acquired and you can feed the various parameters into the model, you will have a situation of garbage-in-garbage-out."
Another concern was that the approach, which uses neural networks to crunch the data, lacks a formal process to apply weights to different datasets to ensure that drill hole data, for instance, gets a higher weighting than samples taken at surface.
Others prefer tried and true approaches to exploration, such as using old mine workings as a prospecting tool, or simply visiting the site to "kick, lick and spit" (thank you to Perth-based consultant Susan Lawson for that image).
Barnett responded to these concerns. He says the statistical approach can be used with sparser exploration data as long as the resulting "broad brush" targets are recognized as such. And weights need not be estimated because the modeling process automatically determines the contribution of each data set. For those concerned with costs, Barnett argues that the expense associated with statistical analysis becomes a tiny fraction of the reward if the method succeeds in pinpointing an economic deposit.
Although nothing replaces finely tuned geological intuition, there are probably several mining camps that could benefit from this level of quantitative analysis of all existing data to pinpoint orebodies hiding in the shadow of the headframe. It's already succeeded in finding new gold in the Porcupine camp of northern Ontario, for example.
As Shanti Kumar, a consultant in Hyderabad, advises: "keep trying neural networks, but validate (them) critically with conventional geological observation."