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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 Carmela Burns on July 19, 2012 technology
The recent rush to find graphite and vanadium deposits to satisfy potential demand in green energy applications is reigniting airborne electromagnetic (EM) methods as highly effective exploration tools.
Graphite and vanadium are both commonly used in steelmaking and both are finding new, high-tech applications such as lithium-ion and vanadium-redox batteries, wind and solar power. In some cases the two materials occur together in nature, allowing geophysicists to use the highly conductive graphite to lead to the more subtle vanadium that can be bound by several different minerals.
As is the case for many accessory minerals, there are no direct geophysical methods for detecting minerals containing vanadium, says Alexander Prikhodko, senior geophysicist with Geotech. Geophysical techniques are able to reflect only indirect indications, or “symptoms”, of the metal and the factors that control its deposition.
Where there is a graphite association, he says, EM methods are highly effective in exploration for vanadium. Tintaniferous magnetite, a common vanadium host, also provides an EM response.
At Triple Nine Resources’ Four Corners iron ore-titanium-vanadium property in Newfoundland, for example, a 2011 helicopter borne VTEM survey conducted by Geotech over newly staked claims extended one high intensity magnetic anomaly and discovered three new ones. The targets occur along (and in close proximity to) the Cabot Fault Zone, part of a globally significant, deep penetrating structure that is the likely source for the mineralized fluids at the Four Corners Property.
Follow-up drilling on the property’s Keating Hill anomaly, which the VTEM survey suggests has double the strike length than that originally outlined, confirmed significant concentrations of all three metals down to a maximum vertical depth of 590 m, including a weighted average grade of 20% Fe2O3 T (total iron), 3.5% titanium oxide (TiO2) and 0.10% vanadium pentoxide (V2O5).
Furthermore, prospecting along the largest of the four anomalies, the Four Corners MAG anomaly (FCMA), confirmed widespread enrichments of titanium – vanadium – magnetite mineralization with assays of up to 48.8% Fe2O3, 12.5% TiO2 and 0.31% V2O5. FCMA has a strike length of at least 4.5 km and a width of is 1.5 km and appears to be part of a large mineralized system that will require more follow up.
The high conductivity of graphite lends itself well to electromagnetic surveys, and there are a number of airborne electromagnetic systems that are being used successfully for vanadium and graphite exploration, including Fugro's HELITEM (time domain) and DIGHEM (frequency domain) systems and Geotech’s VTEM system. Each system has its unique strengths.
Prikhodko notes that there is no single technical characteristic that identifies an EM system as the best for a particular exploration task including finding vanadium deposits. Instead, the electronical and mechanical attributes of the system work together to provide an integrated solution. Just as the loudest singer is not necessarily the best, the EM system with the most powerful transmitter is not necessarily the most appropriate for targeted exploration. The “loudness” of a system must be balanced with timbre, clarity of sound and precision of note, he says.
According to Prikhodko, one of the key technical advantages of Geotech’s VTEM system is the balance between high power and sensitivity. “Balance is achieved through complex engineering, noise reduction in very wide broadband and optimization of the transmitter’s current wave form to use as much of the helicopter’s spare electrical power as possible,” he says.
In this way, VTEM can detect and discriminate between low to excellent conductors using a low base frequency, long pulse width, system calibration and a B-Field derived from integrating data collected at 96 kHz over the entire waveform.
Geotech’s continual development of their technologies has included extensive GX programming within the Geosoft platform to build a highly specialized and integrated solution for quality control, processing, visualizing and presenting VTEM results. “ We utilize Geosoft for QC procedures, data processing, maps creation, parameters calculations and resistivity depth imaging,” said Prikhodko.“ Geotech geophysicists and processors have developed lots of special GXs to accommodate our workflows.”
For vanadium and graphite exploration, and especially when the two materials occur together, EM methods are proving to have the right combination of deep penetration, sensitivity, and spatial and conductance discrimination to detect future deposits of these strategic resources.