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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

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...

A formula for higher hit rates? NexGen may have it

by Virginia Heffernan on May 14, 2015 applied

The methodical, collaborative way the technical team goes about exploration has provided the backdrop for NexGen’s extraordinary hit rate on the Arrow zone of the Rook I property. Shown above: NexGen VP of Exploration Garrett Ainsworth.

NexGen Geologist Justin LaFosse spotting drill collars.

[Click to enlarge]

Rook 1 drilling, Arrow property, Feb 23 2105

[Click to enlarge]

Fury target areas: EM conductors with gravity background.

As exploration moves deeper into the subsurface, achieving a high hit rate is becoming increasingly difficult. Without outcrop or other surface geochemistry to guide the way, explorers are drilling almost blind, relying on sometimes nebulous geophysical signatures to find hidden targets.

Yet by combining geological insight, tailored exploration techniques and comprehensive data compilation, NexGen Energy has hit the buried Arrow zone on the Rook I property that straddles the southwest margin of Saskatchewan’s Athabasca basin in almost every hole.

Rook I abuts Fission Uranium’s Patterson Lake South (PLS) project, which hosts the Triple R deposit, considered one the best grassroots mineral discoveries of this decade. Two years ago, NexGen drilled what looked like a northeastern extension of a PLS EM conductor and intersected strong hematite and clay alteration and sniffs of uranium mineralization at Area A.

A follow up campaign on the Rook I property discovered the Arrow zone in the first hole, and subsequent drilling delineated high grade mineralization over a strike length of 515 m and a width of 215 m in 40 of 42 holes.

Arrow remains open along strike as NexGen continues an 18,000 m winter program with three rigs, stepping out from the original discovery and hitting the stacked sub-vertical mineralized shear zones that represent Arrow with impressive regularity.

In March, NexGen announced the widest high grade intercept the basement gneisses to date: 70 metres grading 2.2% U3O8 from 522 metres down hole AR-15-34b, a 30 m step out from the centre of one of the main mineralized shear zones at Arrow.

How do they do it? To be fair, NexGen has an advantage over most explorers in the region because Arrow – like the neighbouring Triple R deposit - is shaping up to be a relatively large uranium deposit: a knitting needle among sewing needles in the basin’s haystack. And the mineralization is shallow, ranging in depth from 100-820 m compared with greater than 500 m elsewhere in the basin.

The other benefit the company has is experience: VP of Exploration Garrett Ainsworth was the project manager at PLS from 2007-2013; director Andrew Browne, head of the technical advisory, has been involved in uranium exploration since 1969, working in the Athabasca basin since 1988; and director Craig Perry has lead several exploration programs for Rio Tinto and others.

But the methodical, collaborative way the technical team goes about exploration has provided the backdrop for NexGen’s extraordinary hit rate. “It’s a bit like doing a forensic study,” says Ainsworth, who won the Colin Spence award for excellence in global mineral exploration for his efforts at PLS. “The key is to obtain as many layers of data as possible. Then each layer is given a different weighting to prioritize targets. The highest priority weighting, for example, would go to a historical drill hole with good geology, alteration, structure and radioactivity that has not yet been followed up.”

Because the area is so heavily glaciated, the lowest priority weightings usually go to geochemical anomalies most likely explained by bedrock anomalies up-ice, not in-situ mineralization. The exception is radon gas sampling which, although prone to false negative and positive anomalies depending on environmental conditions, is proving to be an effective tool for detecting the shallower uranium mineralization of the southwestern basin such as at PLS and Rook I.

The type of data collected and the way that data is integrated contributes to the drilling success. With a huge swath of ground to cover, NexGen pores through large volumes of historical data from Saskatchewan’s assessment files, importing digital files and manually entering data from paper files into Geosoft Target while georeferencing everything for accuracy. “It’s quite a process, but when you compare the cost of doing that to the cost of redoing the survey, it’s dirt cheap,” says Ainsworth.

Depending on what the historical data reveals, NexGen runs airborne surveys including VTEM, magnetometer, gravity and radiometrics, then integrates the results of those surveys with the historical compilation to narrow down the area of interest.

The company follows up favourable airborne targets with ground geophysics such as TDEM, ground gravity, and DC resistivity, and where applicable, radon gas sampling. Airborne radiometric anomalies are checked by prospecting with handheld scintillometers, and - if uraniferous boulders are found - trenching and glacial studies to determine which way the boulders travelled and their up-ice bedrock source.

All the while, the team is entering new data into Target in order to zero in on the best drill targets. “Target allows us to do comprehensive compilations by tying in historical data with airborne and ground geophysics and our latest geochemical and drill hole data,” says Ainsworth.  “It graphically communicates important information to both investors and geologists. Being able to communicate with two such different groups with one program is invaluable.”

And with every drill hole comes a better sense of the structural controls on the mineralization, a factor Ainsworth says is key to determining where the next “blow out” of uranium will be.

Once the technical team has had time to digest the results of the current winter drill program, NexGen will launch another 18,000 m program to continue advancing Arrow. The company will also test the Fury area on a different conductor corridor 13.5 km southeast of Arrow, where the team has identified six drill targets based on the results of VTEM, ground gravity and magnetics.

Since Rook I has the potential to host three different types of uranium mineralization, Ainsworth expects exploration to continue indefinitely. “The property straddles the present day edge of the Athabasca basin, which is where you want to be to find shallow high grade uranium, not only within basement rocks but also at the unconformity and within the Athabasca sandstone.”



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