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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

December 7, 2016

Geosoft introduces IP and resistivity inversion in VOXI Earth Modelling

Geosoft has added induced polarization and resistivity data inversion to its VOXI Earth Modelling 3D inversion software service. Geoscientists are now able to create detailed 3D models of conductivity and chargeability from IP and resistivity survey data with VOXI. The resulting models can assist in interpreting and targeting regions for mineral and environmental applications...

December 5, 2016

Mexico's Deepwater Round Exceeds Expectations

Some of the world's biggest oil companies showed up Dec. 5 and agreed to invest on the Mexican side of the Gulf of Mexico, proving that deepwater exploration still has a pulse despite challenging market conditions...

November 30, 2016

Magnetic inversion results for Ngamiland available for download

A regional-scale geophysical inversion of magnetic field data in the Ngamiland region of northwestern Botswana is now available for download from the Botswana Geoscience Portal, a partnership initiative of the Botswana Geoscience Institute, industry sponsors and Geosoft...

November 30, 2016

LIGO Resumes Search for Gravitational Waves

After a series of upgrades, the twin detectors of LIGO, the Laser Interferometer Gravitational-wave Observatory, have turned back on and resumed their search for ripples in the fabric of space and time known as gravitational waves. LIGO transitioned from their engineering test runs to full science observations at 8 a.m. Pacific Standard Time on November 30...

November 9, 2016

International Volcano Scientists Unite

For the first time, the United States will host the international Volcano Observatory Best Practices workshop, previously held only in Italy. The workshop will take place this month in Vancouver, Washington. It is designed specifically for volcano observatories around the world and their staff to exchange ideas and best practices with each other...

October 4, 2016

USGS Assesses Mineral Potential for Sagebrush Habitats in Six Western States

USGS has completed a comprehensive assessment and inventory of potential mineral resources covering approximately 10 million acres of Federal and adjacent lands in Idaho, Montana, Nevada, Oregon, Utah and Wyoming...

October 3, 2016

Uganda Targets Up to U.S.$100 Million for Mineral Exploration

Uganda is well endowed with mineral resources and, like many naturally-gifted African countries, is becoming keen on ensuring that these resources play a transformative role in its long-term structural transformation dream - the Vision 2040...

September 9, 2016

Small-Scale Fishers Get A Big Boost With First-Of-Its Kind Impact Investment Fund

Conservation organization Rare announces the Meloy Fund for Small-Scale Fisheries at Our Ocean Conference. The Global Environment Facility, one of the largest funders of conservation worldwide, will be investing $6 million into the fund...

September 1, 2016

Scientists take to the skies to track West African pollution

Scientists operating research aircraft over West Africa have detected organic materials in the atmosphere over a number of urban areas, contributing to concerns of the rise in pollution across the region...

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...

Discovery at the Bingham Canyon Mine

Fresh rendering of old drill data inspires deeper drill campaign and leads to new discovery at Rio Tinto’s Bingham Canyon mine

by Virginia Heffernan

It’s hard to imagine a better poster child for the practice of marrying historical data with modern processing technology than the recent molybdenum discovery at the Bingham Canyon copper mine in Utah.

In late September, Rio Tinto announced the discovery of massive molybdenum discovery beneath the floor of the open pit mine that could rival Colorado’s Climax and Henderson, two of the world’s biggest molybdenum deposits.

The find is extraordinary because Bingham Canyon has been operating for more than a century and, while the main deposit still has legs, no one would have predicted that the world’s next big metal discovery would occur in such a mature environment.

The other fascinating aspect of the news is that the discovery was actually made in 1970, but only became clear when Kennecott Utah Copper, a wholly-owned subsidiary of Rio Tinto, applied modern data processing and visualization techniques to historical drill logs.

“We have put tremendous effort put into converting our geologic and drillhole data into a digital format,” says Gerry Austin, Superintendent of Geology for the Bingham Canyon mine. “Most of the effort was completed in the 1990s but it was not until the early 2000s that computer speed and advancements in 3D software allowed geologists to view deposits in 3D space.” 

By 2004, molybdenum was becoming increasingly sought after for its ability to enhance the hardness, toughness, and corrosion resistance of metal alloys, particularly stainless steel. The price had increased 8-fold since the early 2000s to more than US$40 per pound and, as a result, Kennecott decided to revisit old drill logs that recorded molybdenum as part of a brownfields exploration program at Bingham Canyon.
 
“It was the ability to spin and view the deposit in any direction that highlighted the two 1970 drillholes that had intercepted the top part of the mineralized zone,” says Austin.

The fresh rendering of the old drill data inspired the mine exploration team to launch a drill campaign below the floor of the pit, which is already more than kilometre deep and getting deeper everyday. Sixteen holes intersected high-grade molybdenum mineralization within a steeply dipping arcuate body that extends at least 1,000 metres below the pit floor.

Based on the drilling so far, the deposit is estimated to contain in the order of 500-600 million tonnes grading 0.1-0.15% molybdenum. Hosted mainly by monzonite and occurring as quart-molybdenite veinlets and as molybdenite disseminations and fracture fillings, the mineralization remains open.

“We expect to see more as we explore deeper and laterally,” says Austin.

Bingham Canyon, though primarily a copper deposit, has always been a significant gold and molybdenum producer. In 2008 the company announced plans to build a US$270 million facility to improve molybdenum recoveries. The proposed project is expected to increase Bingham Canyon’s molybdenum production by 15% over the 2008 rate of 10,600 tonnes (23.4 million pounds).

Bingahm Canyon is a classic copper porphyry with a fairly uniform distribution of sulphide mineralisation, mainly chalcopyrite. The existing pit will be worked out by 2019 but  Kennecott is evaluating the feasibility of deepening the pit to add an extra 2.83 million tonnes of copper resources and extend the mine’s life from 2019 to 2036.

The new discovery is considered a high-grade extension of the rich molybdenum zones with the main deposit. While the average grade of the molybdenum in the open pit reserve is 0.044% Mo, the grade within the new exploration target is up to 3.5 times richer. The mineralization appears to wrap around the barren core of the porphyry copper deposit in the northeast and southeast sectors of the deposit.

“My initial thought is that the moly is geologically controlled within favourable horizons,” says Austin, though he says his team needs more time to study the new exploration target to determine how it fits with Bingham Canyon’s current geological model.

Locally, the molybdenum mineralization reaches the surface on the eastern side of the pit bottom, where it has contributed to higher than average molybdenum head grades from 2004-2007. Batch flotation testing of composite samples indicated molybdenum recoveries of about 95% in rougher flotation.

Austin says further exploration of the giant new deposit and potential similar deposits in the area are on hold while management determines its exploration priorities. The price of molybdenum has dropped to less than US$15 per pound since the exploration commenced in 2004 and the whole Rio Tinto group has slashed exploration for both greenfield and brownfield projects to US$115 million this year from US$235 million in 2008. Expenditures will remain flat in 2010 as Rio Tinto awaits a global recovery.

And there are, as yet, no plans to develop the new deposit.

“While it is likely that underground development could access both the deep molybdenum body and deep porphyry copper and skarn mineralization, the feasibility of developing such a mine has not been established,” Rio Tinto states in a fact sheet on its web site.

Still, it seems a sure bet that Rio Tinto will develop the giant resource as molybdenum prices improve in step with the global recovery and consequent increased demand for stainless steel. Molybdenum price forecasts from producers are calling for US$11 per lb average price for 2009, down from US$29 in 2008, but up from the first-half average of US$9, according to purchasing.com, a free on-line magazine that provides the latest market forecasts, supply chain tactics, and technologies of goods purchasers.

Companies never know what they might find when they pull out their dusty core logs and map sheets and start digitizing and visualizing the data in 3D. The Bingham Canyon molybdenum deposit may be the first major deposit to be found that way, but it is unlikely to be the last.