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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...

Airborne Survey Focuses Exploration in the Yukon

Airborne geophysics in combination with geochemistry is helping to unveil more deposits in the Yukon's White Gold district.

By Virginia Heffernan

The discovery of the White Gold deposit by Underworld Resources in 2009 touched off a massive exploration rush in central Yukon that continues to grow in tandem with new discoveries of epithermal style lode gold and copper-gold-molybdenum porphyries.

Until recently, geochemistry has been the exploration technique of choice, specifically deep auger soil sampling successfully introduced to the area by prospector Shawn Ryan (see accompanying profile).

But geophysics is starting to play a more significant role in the minefinding process for the same reason soil sampling works so well: bypassed by the glaciers, the region's bedrock has had millions of years to weather undisturbed. Airborne geophysics sees through the resulting overburden to identify underlying structures or geological contacts that control mineralization, and can help the geochemistry teams narrow down sampling locations.

One of the companies flying extensive airborne geophysical surveys this year is Taku Gold Corp., a major claimholder in the White Gold district with a total of 76,238 hectares.

Having staked such a large land package, Taku needed a way to focus its exploration efforts. So the Vancouver-based company hired Precision Geosurveys to fly airborne magnetics and radiometrics in order to collect basic information about the underlying bedrock before launching soil sampling surveys.

Precision used a helicopter to fly 2,500 line kilometres at a 100 metre line spacing over Taku’s properties. Its high resolution magnetometer system is designed to detect bedrock units, structure and alteration. The radiometric system, consisting of a multichannel spectrometer with state-of-the-art design and large gamma ray sensing crystals, helps determine lithologies and alteration.

Using Geosoft’s Oasis montaj, Precision converted the resulting data from a binary file to a GDB file to display all the data channels. After the conversion, Precision ran Geosoft scripts and filters to eliminate noise and enhance the data to identify potential anomalies.

For instance, radiometric data measure the energy of gamma rays being emitted to infer the presence of particular radioisotopes. Different rock types and alteration patterns produce different radioactive signatures, but features such as swamps and lakes can attenuate these signatures. Precision used Geosoft to generate maps with different radiometric isotope ratios to filter out the effect of attenuation.

Using a leveling tool - an extension of Oasis montaj - Precision leveled the survey and tie line data to create the final processed data, and then created grids to display the gridded data. For more advanced analysis, Precision used MAGMAP, a filtering extension, to enhance the gridded dataset. To produce the final product, Precision created basemaps on top of the grids and imported topography into the background. 

“The mathematical algorithms developed by Geosoft speed up our processing and are fully compatible with other GIS programs,” says Precision geophysicist Jenny Poon. “We also use Geosoft to generate the flight grid and the kilometers per line. We can calculate a quote for the client from that information”.

In the White Gold district, mineralization appears to be concentrated along northwest-trending fault structures at the contact between gneisses and ultramafic rocks. There is also an association with Cretaceous intrusions. Precision found indications of both on Taku’s properties.

“In the surveys completed for Taku, Precision identified numerous linear structures that may represent faults as well as numerous rounded features that may represent buried intrusions,” says Mark Feneke, a Taku director and professional geologist guiding the exploration program.

Taku is using the geophysical results to plan deep-auger soil geochemical surveys, targeting both the prospective linear features that may be faults and the rounded features that may be buried intrusions. This year, the company plans to collect 30,000 soil samples and fly several thousand kilometres of geophysics, then follow-up the results with 7,500 m of drilling.

The White Gold District lies within the Tintina Gold Belt, a 200-km-wide, 1,200-km-long arc extending from northern British Columbia into southwest Alaska. This metallogical province has produced 30 million ounces of gold in the past, but within the White Gold district exploration is just beginning.

Poon estimates that only about 10% of the area has been flown so far, suggesting more deposits are yet to be unveiled by airborne geophysics in combination with geochemistry in this extensively overburden-covered area.