The people, science and technology behind discovery

Subscribe to the Magazine

Get new articles sent directly to
your mailbox.


Join the network

Twitter Updates Group Forum

Earth Explorer is an online source of news, expertise and applied knowledge for resource explorers and earth scientists. Sponsored by Geosoft.


News & Views

News Archive

August 17, 2016

New IGS Xplore prospectivity maps for Botswana

International Geoscience Services have released a series of base metal prospectivity maps for the Ngamiland District of northwestern Botswana using free geodata available on the recently-launched Botswana Geoscience Portal, hosted by Geosoft. The maps identify favorable areas for copper, zinc and lead mineralization using geological, geochemical and geophysical datasets downloaded directly from the portal.

August 11, 2016

NexGen Makes New High Grade Discovery

NexGen Energy reported the discovery of a new high grade zone of mineralization 4.7 km northeast of the Arrow Deposit as part of an on-going summer drilling program on its 100% owned, Rook I property, Athabasca Basin, Saskatchewan...

August 10, 2016

Rampion UXO Disposal to Take Place This Week

E.ON has confirmed that the two unexploded devices, detected along the Rampion offshore cable route will be safely disposed this week following the consultation with the Marine Management Organisation...

August 9, 2016

Diamonds In The Rough: E&Ps Find New Reserves In Mature Basins

The oil industry’s history demonstrates clearly that new plays and prospects have long been found in mature basins that were thought to be well on the way to being squeezed dry. Through the acquisition of new data, developing new concepts and coming up with fresh interpretations, long-producing basins around the world from the North Sea to Malaysia have continued to reveal new riches...

August 8, 2016

Northern Shield Identifies High Quality VTEM Targets at Séquoi

Northern Shield Resources announced the results of the interpretation and modelling of the VTEM survey from the Séquoi Property in the Labrador Trough of Quebec . Séquoi is owned 100% by Northern Shield and is being explored for Noril'sk style Ni-Cu-PGE massive sulphides. After geophysical modelling and interpretation of the VTEM data from Séquoi, six VTEM anomalies of significant interest have been identified...

August 3, 2016

Rio Tinto tailors big data drive to copper

Rio Tinto will put the weight of an exploration big data push and its newly-formed Growth and Innovation group behind its desire to identify a "tier 1" copper asset. Speaking at the annual Diggers & Dealers conference in Kalgoorlie, Growth and Innovation group executive Stephen McIntosh said Australia was "overdue for a tier 1" mineral discovery of any type...

August 1, 2016

Tetra Tech Awarded $200 Million Navy CLEAN Contract

Tetra Tech announced that it has been awarded a $200 million, single-award contract by Naval Facilities Engineering Command (NAVFAC) Atlantic. Through the Comprehensive Long-term Environmental Action Navy (CLEAN) contract, Tetra Tech will provide environmental engineering support services to installations within the NAVFAC Atlantic Area of Responsibility...

May 3, 2016

NATO Science for Peace and Security (SPS), MODUM Partners announce "Young Scientist Summer School on Sea Dumped Chemical Weapons"

This international project cooperates closely with CHEMSEA (Search and Assessment of Chemical Weapons) Project for and sharing and knowledge transfer...

April 12, 2016

Monday mad rush for gold stocks

Renewed optimism about the outlook for gold saw investors pile back into gold stocks, pushing many stock to 52-week highs in heavy volumes...

April 11, 2016

Medgold Resources: Continues to Expand the Boticas Gold Project, Portugal; Proposes $200,000 Private Placement

Medgold Resources is pleased to announce new assay results from contiguous rock-chip sampling from the Limarinho South zone at its Boticas gold project in Portugal, which include a highlight of 6.0m @ 5.7 g/t Au...

April 8, 2016

De-carbonizing our energy sector

Nuclear energy currently provides around 11 percent of the world's electricity. China, the European Union, the United States, India, Russia, South Korea, and other nations’ have major existing fleets...

April 1, 2016

Follow-Up Drilling Results Indicate Wide Gold Zones at Hendricks Gold Discovery

Gascoyne Resources Limited announced that it has received the final assay results from the 10,000 metre aircore exploration drilling programme...

March 26, 2016

The Oil Market Is Finally Hitting Its Breaking Point

After a significant reduction in investments over the past two years, oil companies can no longer overcome the production declines from legacy wells...

March 15, 2016

N-Sea Expands into the French Offshore Wind Industry

Subsea IMR provider, N-Sea, has signed a letter of intent with CERES Recherches & Expertise Sous-Marine and TechSub Industrie Environement, to provide subsea survey, installation and remediation services to the French offshore wind industry...

March 9, 2016

PDAC 2016 Convention Exceeds 22,000 Attendees

Optimism and opportunity abounded at the PDAC 2016 Convention of The Prospectors & Developers Association of Canada in spite of recent industry challenges...

March 3, 2016

6 Alpha Launches EOD Contracting Division

6 Alpha Associates, a specialist risk consultancy practice, with expertise in the assessment and management of unexploded ordnance, has launched a dedicated explosive ordnance disposal division...

February 10, 2016

Cameco's new uranium discovery revealed

Canada's top uranium producer has a significant new discovery nearby to one of its largest existing mines...

February 9, 2016

NexGen Drills Most Intense Mineralization to Date at Arrow

NexGen announces further results from its on-going six rig 30,000 m winter 2016 drill program on its 100% owned Rook I Property in the Athabasca Basin, Saskatchewan...

February 9, 2016

Rio Tinto scales up its big data ambitions

Rio Tinto is opening its "vast troves" of exploration data to junior explorers in the hopes they will help sift for opportunities and supply ideas and labour...

February 8, 2016

Online portal improves access to geoscience data from Africa

The Botswana Geoscience Institute is launching a Geoscience Portal...

February 8, 2016

5 Best Minerals & Fossils To Buy With Your IRS Tax Refund

You just got your IRS tax refund and now you're presented with some cash to go out and buy one of a kind minerals and fossils from your local...

February 5, 2016

World's largest offshore windfarm to be built off Yorkshire coast

Dong Energy makes final investment decision on 1.2-gigawatt project that will power more than a million UK homes...

February 2, 2016

World's top 10 rookie gold mines

These high-grade mines will soon start competing with gold mining's industry leaders ...

January 25, 2016

Exxon Mobil Corp's defiant outlook predicts Canadian and Venezuelan oilsands output will 'quadruple' over next 24 years

In sharp contrast to the grim medium-term prognosis for the Canadian oilsands, Exxon Mobil Corp. is predicting sunnier times for bitumen in the decades ahead...

January 23, 2016

Magnetic Survey Keeps Cost Down

At a contaminated furniture factory site in North Carolina, a reconnaissance magnetic survey was conducted toward the end of a Phase 2 investigation ...

It Pays to Look Deeper

Deep earth imaging is revealing previously overlooked and undiscovered
mineral bodies

By Graham Chandler

The mountains between British Columbia’s Highway 37 south of Dease Lake and the Alaska border have long been a prolific supplier of important mineral resources. Ten thousand years ago Canada’s indigenous peoples were accessing some of the world’s best obsidian - a natural volcanic glass sharper than surgical steel - from Mount Edziza and trading it all over the continent.

Fast forward to the 21st century. The bounty continues. This region can now boast two of Canada’s most significant copper, gold and silver deposits: Barrick Gold’s Eskay Creek Mine and NovaGold/Teck Resources’ Galore Creek Project. NovaGold alone has reported resources of 7.4 million ounces of gold, 117.1 million ounces of silver and 8.5 billion pounds of copper. And now thanks to a new deep imaging technique, Romios Gold Resources hopes to reveal even more in this rich paradise.

Romios Gold had begun intensively studying regional geologic maps which suggested the underlying rocks and mineralization between the two projects held serious promise and so in late 2004 began acquiring land positions there. Exploring surface mineralization supported their enthusiasm when it appeared the rocks may be closely related to the porphyry copper-gold-silver deposits at the nearby Galore Creek Project. They followed up with soil geochemistry, mapping and silt sampling programs on the Trek property in 2006.

Soon they had a diamond drilling program underway. “It was based on plain old hand drawn maps and geologic work,” says Scott Close, Principal Geologist for Romios Gold. “The very first time a drill hole was placed at the North Zone on Trek, we hit great breccia-hosted mineralization. This indicated we were within the cupola area of this porphyry so we expected the body to be nearby.”

Their hunch was right. Drilling successes in 2008, 2009 and 2010 discovered wide zones of gold-copper mineralization at the North Zone and also identified a new area of prospective copper-gold mineralization called the Tangle Zone. 2010 drilling results suggested the breccia and mineralization at the North Zone extended at least 700 by 550 metres, to a depth of 450 metres and - more importantly - it appeared that the mineralization may be traceable to a mineralized porphyry body beginning 550 to 600 metres depth.

So at this point what was really needed, before committing to further drilling, was a look deeper - beyond their drill depths, into where they expected that porphyry body to be. That’s when they brought in the Titan24 Deep Earth Imaging system. “With the Titan24 we could really get a good idea of where we sat,” recalls Close. “Predecessors to this system had imaged the Galore Creek mineralized body as we know it today, but the resolution was lower.”

The Titan24 Deep Earth Imaging is a product of Quantec Geoscience. Ron Vermey, Quantec’s President and CEO, describes what makes the system unique. “It’s a combination of array geometry,” he says. “We use a grid array on the surface that’s 2400 metres long, which gets us down to depths of 500 metres or more with IP (induced polarization, or chargeability) and resistivity, and 1500 metres with MT (magnetotelluric).” He says because of low signal strengths from such depths they also use highly sensitive electronics which can pick up very small signals. “That’s important when you’re looking at depth,” he says. The processing is important too, to recover small signals against an often noisy background.

The Titan24 system’s deep imaging capabilities were tailored for Romios Gold’s Trek property. And there was another attraction. “Quantec said they could actually couple their deep MT, their high resolution IP and resistivity - of which we hadn’t conducted in detail on any of on the Trek property - with drill results from portions of the surveys,” says Close. “So it was an excellent opportunity to do all three, allowing us to associate any anomalies, or lack thereof that appeared with data we already had and project into new territory.”

Undertaken in the summer of 2010 close on the heels of that year’s drilling program, the Titan24 Deep Imaging’s three lines revealed what Romios had suspected. The survey identified a large deep conductor 500 by 300 by 200 metres high, across all three lines in the Trek property’s North Zone; and it still remains open to the north, east and south. As Romios Gold says on its website, “this new feature, which lies east and below the previous drilling and occurs from 500 to 675 metres below surface, represents the main target for future drilling.”

The analysis and interpretation of the DC, IP and MT results also identified several chargeable anomalies above the deep conductive zone. They were reported to coincide reasonably well with the results of the existing 23 drill holes on the North Zone. Romios intends to drill test these anomalies in its upcoming program too.

Close describes the benefits that Titan24 brought. “It’s a highly sensitive system,” he says. “So it accurately reflects an interplay among the mineralization, alteration, structure and geology of the deposits; when coupled with different reference information like drilling or geochemistry, the survey provides a complete exploration picture.” 

Quantec uses Geosoft Oasis montaj to generate all of Titan24’s sections and plan maps. The Geosoft Viewer allows Romios and other customers to easily view Titan24 maps, turn layers on/off as needed, and enables them to convert them into geo-referenced images for export in a vertical plane. They can bring these directly over into GIS and various other programs.

The mapping workflow was streamlined a few years ago when Geosoft designed a custom solution for the Titan24 application. A Titan24-specific menu blended seamlessly with Geosoft’s ability to import, view, process, and share data sets and images in one integrated environment. It allowed Quantec to produce client-specific presentations such as Titan24 Custom Inversion Sections and Plan maps, Voxel presentations and 3D inverted data. Vermey adds. “We’re able to efficiently visualize drillhole databases, create Titan 2D and 3D models, integrate client data and pseudosection displays for conventional data within one environment, for consistently high quality results.”

The inversion presentations were critical. “The regular DC-based inversion on the MT did a great job for the two southern lines, which indicated a conductor consistent with the geology in the area,” says Close. “Major faults overpowered the anomaly at depth on the northern line. So, applying a static shift upon the underlying resistivities to remove the influence of the overlying faults affecting this line, Quantec was able to identify the conductive anomaly striking through all three survey lines. Knowing the geology was useful for constraining the inversion.”

The final subsurface processing that brought it all together was produced using Oasis montaj. “The contouring inherent in Geosoft can histogram-equalize (evenly spread colors over a non-linear set of values) better than any other program I’ve ever used,” says Close, “so it makes incredibly beautiful maps.” He says once they had that image, they realized their drilling had just missed the conductive body. “The image confirmed what we had suspected: we had drilled smoke near the flame.”

Now, armed with this new deep picture, they’ve picked out new drill locations. “We will have one drill hole penetrate down the middle, right at the heart of the system, and verify the target,” says Close. “Then, we’ll step out. We will drill holes further to the east through the higher IP anomalies that coincide with surface mineralization, and trace the IP anomalies back toward the deeper MT target.” It’s a whole new level of confidence.  “The Titan24 system has greatly enhanced our ability to focus our future drilling at these depths,” he says.

Vermey says Titan24 offers benefits because deposits are getting deeper. “As much as market economics say today ‘look for shallow deposits’, in many areas particularly in mature jurisdictions like North America many of the deposits are deeper, harder to find, or under cover,” he says. “So for ten years Quantec’s Titan24 method enables you to look almost as deep as you want to detect these ore bodies. In some places like Arizona you are looking down 1300 metres for porphyry copper.” And, he adds, with recent rises in commodity prices that certainly makes it economic to go back and re-explore old mines and camps. “Titan24 is a proven system in a mine site environment so you can come up with some good data out of what is normally a noisy environment.”

Romios used the Titan24 survey even in the absence of any existing drilling information - in the Tangle zone of their Trek property. They had nothing but a large soil anomaly, on which Close says “it’s hard to find funding to drill anomalous soils.” So they ran a single Titan24 line across the zone. It revealed a one-to-one correlation among all three DC, IP and MT surveys, exposing a deeper anomaly connected with the anomalous soils at surface. “That single line added enough confidence for us to attract investors to the potential of this new area,” says Close. “It brought us a wealth of possibilities. Really, to me, Titan24 is the new wave of ground geophysics.”