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Earth Explorer is an online source of news, expertise and applied knowledge for resource explorers and earth scientists.
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News Archive

July 21, 2014

HPC's Role in Energy Exploration

How high-performance computing helps companies track down hidden fields of oil and natural gas. The easy oil and gas has already been extracted, and sophisticated discovery and extraction techniques are needed to extend production...

July 20, 2014

ENI signs deal to expand oil, gas exploration in Congo

Italian oil and gas group Eni said it signed a deal to explore for hydrocarbons in the Republic of Congo's coastal basin, expanding its foothold in sub-Saharan Africa's No. 4 oil producer...

July 20, 2014

Cameco: Light At The End Of The Japanese Tunnel?

Declining Japanese bond spreads bode well for the supply/demand dynamics of the uranium market and uranium stocks such as Cameco...

July 20, 2014

The tiger roars as the dragon sleeps

India's coal demand could hit 787 million t this year, according to coal and power minister, Piyush Goyal, with imports required to make up a more-than 200 million shortfall in domestic production...

July 14, 2014

Geosoft previews new Voxel Assisted Layered Earth Modelling technology for imaging base of salt

Geosoft previewed new Voxel Assisted Layered Earth Modelling (VALEM) technology at the EAGE 2014 in Amsterdam. Delivered within Geosoft’s GM-SYS 3D gravity and magnetic modelling environment, VALEM is a cloud-based gravity inversion service that improves imaging of base of salt and sub-salt regions...

June 30, 2014

Digital Tools for Mines Help Maintain a Competitive Edge

Many mining executives are convinced there’s really no alternative: either join the industry’s quickening interest in digital technology or risk losing ground...

June 24, 2014

Hottest lava eruption linked to growth of first continents

A collaborative research team has discovered an important link between the eruption of Earth's hottest lavas, the location of some of the largest ore deposits and the emergence of the first land masses on the planet - the continents - more than 2500 million years ago...

June 16, 2014

Drilling activity near Chibougamau: More than just Monster Lake

Quebec's historical Chibougamau mining district, located within the prolific Abitibi Greenstone Belt, is attracting renewed attention. Against a background of lackluster gold prices and generally low levels of exploration activity worldwide, one of the most recent market-dominating announcements came from the Monster Lake joint venture among IAMGOLD Corp. (50%), TomaGold Corp. (45%), and Quinto Real (5%)...

April 2, 2014

TGDG Mini-Symposium on Mexico Exploration

On April 9, the TGDG is presenting a mini-symposium on Mexico Exploration: Finding the Treasure of the Sierra Madre and more. A portion of this event is being broadcast online free of charge...

Closing the Discovery Gap:
Exploring Deeper into the Subsurface

As spending goes up, discovery goes down:
How do we close the widening gap?

By Virginia Heffernan

The cost of mineral exploration continues to rise, with global spending heading towards US$14 billion this year, yet rates of mineral discovery have been on the decline since the 1980s. Is there a way to reverse the trend?


Professor Bill Morris and Research Scientist Hernan Ugalde of the School of Geography and Earth Sciences at McMaster University

Perhaps, says Professor Bill Morris of the School of Geography and Earth Sciences at McMaster University, but only if explorers begin to integrate geoscience information in such a way that they can see through rock and overburden to find buried deposits.

"The reality is that the old days when prospectors would go out there and find a mineral deposit on the surface are gone," he says. "We have to expand our search into deeper areas and use newer technology to enhance our search capabilities."

That shift in exploration methodology will require training, more efficient use of exploration data, and interdisciplinary cooperation: while geophysics may be the most obvious tool for exploring the subsurface, it cannot be used in isolation.

"The new frontier is the integration of geoscience information," says Morris.  "Geophysics will take you so far, but geophysics on its own will never give you a complete answer."


The Bathurst Camp in the lead-zinc mining region in New Brunswick
(Click to enlarge)

In Canada, the federal government is taking the threat of declining discovery rates seriously by committing $25 million over five years to find new base metal reserves in established mining communities. One of the main components of the Geological Survey of Canada's Targeted Geoscience Initiative (TGI), now in its third phase, is the integration of industry and government data collected over the years to conjure up new images of old camps with the hope of discovering previously undetected ore.

The TGI also aims to produce new geological, geophysical maps and geochemical maps of the target areas, create three-dimensional representations of areas with the highest base metal potential, and come up with new and improved methods to map hidden and deep-seated base metal deposits.

In the Flin Flon mining camp of northern Manitoba, for instance, the TGI completed a 2-D high-resolution seismic survey to help identify buried VMS deposits after the GSC's geological mapping in the area suggested a different structural model for the mining camp that was best tested by seismic tools. The Flin Flon deposits have high acoustic impedance relative to typical host rocks because of their mineral make-up (pyrite, pyrrhotite, sphalerite, and chalcopyrite).

"Before we turned up, the exploration techniques were pretty standard," says Simon Hammer, TGI's program manager in Ottawa, who explains that seismic has not been traditionally been used in mineral exploration, especially in relatively urban areas such as Flin Flon that have background noise. "The fact that the major stakeholder in the area then decided to follow up with 3D seismic clearly indicates that we were able to influence their exploration strategy."

Another TGI target area, and one of the focuses of Morris's research, is the Bathurst lead-zinc mining region in New Brunswick, an old camp that desperately needs new life. The area's main mine, Brunswick, is expected to close by 2010 and maybe even earlier given current metal prices, sucking about $100 million per year out of the local economy and putting 800 people out of work. Junior Blue Note Mining is also preparing to shut down the Caribou and Restigouche lead-zinc mines after less than a year of commercial production.


Vegetation and glacial overburden make it difficult to map the geology
of the Bathurst Camp.

The VMS deposits of the Bathurst camp lie in an ancient back-arc basin broken and twisted by multi-generational folding, faulting, and thrusting of several geological blocks and slivers. But the complex geology is difficult to map because most of the surface is covered by vegetation and glacial overburden, says Hernan Ugalde, a research scientist at McMaster working closely with Morris in partnership with TGI.

That's where geophysical surveys integrated with geochemical and drilling data will play a crucial role in assessing the near-surface and subsurface geology and potentially pinpointing new mineralization.

To that end, Hernan is running detailed gravity surveys (100-200 m spacing) over three VMS deposits in Bathurst - Chester, Caribou and Armstrong B – to test a theory that there is a correlation between the vertical gravity gradient and the presence of mineral deposits in the Bathurst camp.

The push from government and academia is a good first step, but the private sector must also get smarter and more efficient about how it deals with exploration data in order to make new discoveries, the McMaster researchers say. Junior companies in particular are missing the opportunity - for lack of knowledge and/or manpower - to use technology in their favour.

"Junior exploration companies, and even some senior companies, will often chase a geophysical anomaly," says Ugalde. "They may have very detailed geophysical information, but instead of going the extra mile to analyze the data and do some modeling to see, for example, what the actual plunge of the orebody is, they just drill it. But if you don't know the angle of your orebody, you can miss it."


Caribou Deposit: Magnetic Refinements (Worms and Euler Deconvolution)

Armstrong B Deposit: Structural Mapping.
Geology and multiscale edge analysis (Worms)

Ugalde and Morris urge companies to slow down and hire the expertise required to analyze their data properly, especially in this era of non-stop data generation.

"It's the difference between brute force and finesse in exploration," says Morris. "Should you put more money into boreholes, or should you be spending a little more money and time trying to formulate a model?

Morris says the process of creating an exploration model has become much easier and more efficient with the advancement of exploration software, such as Geosoft, which provides a platform for integrating different datasets (e.g. magnetic, geochemical, topographic), bringing them all together as a single resource.

The ability to view these images in 3-D through GIS is also a crucial breakthrough, he says, because ore deposits are, by nature, three dimensional. The latest versions of Oasis montaj and Target, Geosoft's borehole data visualization software, allow geoscientists to work seamlessly between their Geosoft and GIS (ESRI) files without leaving the Geosoft environment.

Increased access to data and the technology to process high volumes of data in meaningful ways are two main ingredients in the new search for mineral deposits. Training is the third. As part of its mandate, TGI3 is placing significant emphasis on training university students in the broad range of skills they will require to serve the mining sector, including providing them with summer jobs in the field.

Morris agrees that the industry badly needs an influx of qualified people that can make sense of data. With lots of user friendly software available, almost anyone can generate images, but only skilled personnel can separate what is meaningful in the data from what is not.

"You need direction from people with training who know how to integrate the data and understand what is behind those purple dots that you are chasing," he says. "It is in our nature to push the data set as hard as we can, to extract as much information as we can. But you're doing that at the expense of reality in some cases."