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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...

Can statistical analysis reverse the trend of declining discovery rates?

by Virginia Heffernan on September 11, 2012 expertise

What if you could generate a map that identified not only exploration targets, but also the likelihood of those targets becoming economic deposits? The authors of the cover article for July’s edition of SEG Newsletter say this kind of “radical approach” to exploration is both possible and necessary.

“The decision about where to look is too often based on an informal interpretation of partial information rather than quantitative analysis of all the available data,” say Colin Barnett and Peter Williams, principals of data mining firm BW Mining and authors of A Radical Approach to Exploration: Let the Data Speak for Themselves. “If we are to improve the discovery rate, we need to put more effort into targeting, or deciding where to look.”

The authors say explorers can increase their chances of success several fold by using statistical analysis in known camps with good quality databases. Advances in pattern recognition combined with greater accessibility to government datasets and lower costs for data storage and processing make it possible to not only pinpoint targets, but to determine the expected economic costs and rewards of each target.

That approach had a 50% success rate in finding more gold in the Porcupine camp of northern Ontario. The jury is still out on the duo’s most recent study area, the Eastern Goldfields North (EGN) portion of the Yilgarn craton in Western Australia.

“The favorable ground is almost completely taken in the EGN, so we need to come to suitable arrangements with current license holders,” Barnett said in an e-mail. “But there are targets on land held by most of the major players.”

The EGN covers about 165,000 km2,or a landmass roughly the size of Wisconsin or Uruguay. The area contains a high concentration of known gold deposits, public access to modern data, and less than 10% outcrop, making it a prime candidate for detailed statistical analysis of geological, geochemical and geophysical results.

Barnett and Williams’s analysis may be beyond the grasp of the average geoscientist, but it involves inputting all the layers of primary exploration data, such as magnetics and lithology, as well as the derivatives of that data, into neural networks. After taking into account all the available data for EGN, for example, the authors ended up with more than 250 layers representing a mindboggling 15 Gb of gridded data files.

The statistical approach allows explorers to quantify the relevance of each data set. In the EGN case, biogeochemistry (sampling the leaves of mulga trees) and geological structure (the area’s gold occurrences are commonly associated with major shear zones, secondary faults and hinge areas of antiforms) proved to be the most informative, while magnetic data was the least helpful.

The EGN study generated more than a dozen high priority targets. Some of them are brand new, but most occur in established camps within a few kilometres of operating mines or old workings.

Will this kind of high level statistical analysis revolutionize exploration in known camps and other areas with plentiful data? Or does the cost and expertise required outweigh the benefits of being able to pinpoint targets with a high probability of success?

Editor's note:

This article has generated lively discussion on Earth Explorer's Linked In group. Group members pointed out some limits to universal application of a statistical analysis approach, perhaps the biggest hurdle being the need for comprehensive geological, geophysical and geochemical datasets from areas that have already undergone exploration to some degree.

Lyndon Hardy, senior exploration geologist for Abra Mining in Perth, put it best: "Until there is sufficient regional data acquired and you can feed the various parameters into the model, you will have a situation of garbage-in-garbage-out."

Another concern was that the approach, which uses neural networks to crunch the data, lacks a formal process to apply weights to different datasets to ensure that drill hole data, for instance, gets a higher weighting than samples taken at surface.

Others prefer tried and true approaches to exploration, such as using old mine workings as a prospecting tool, or simply visiting the site to "kick, lick and spit" (thank you to Perth-based consultant Susan Lawson for that image).

Barnett responded to these concerns. He says the statistical approach can be used with sparser exploration data as long as the resulting "broad brush" targets are recognized as such. And weights need not be estimated because the modeling process automatically determines the contribution of each data set. For those concerned with costs, Barnett argues that the expense associated with statistical analysis becomes a tiny fraction of the reward if the method succeeds in pinpointing an economic deposit.

Although nothing replaces finely tuned geological intuition, there are probably several mining camps that could benefit from this level of quantitative analysis of all existing data to pinpoint orebodies hiding in the shadow of the headframe. It's already succeeded in finding new gold in the Porcupine camp of northern Ontario, for example.

As Shanti Kumar, a consultant in Hyderabad, advises: "keep trying neural networks, but validate (them) critically with conventional geological observation."