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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...

IAEA publication reviews advances in geophysical methods for uranium exploration

by Graham Chandler on May 27, 2013 library

Publication of a new eBook, Advances in Airborne and Ground Geophysical Methods for Uranium Exploration, proves timely as many countries see a rise in uranium exploration.

The publication is part of the IAEA’s nuclear energy series (no. NF-T-1.5, 2013). A free PDF version can be downloaded from Print copies of the book can also be ordered from the website .

With gaps between the start of exploration and production typically stretching from 15 to 40 years many countries have seen a rise in uranium exploration since 2005. The world’s capacity for generating nuclear energy is expected to grow to between 511 and 782 GW by 2035. That could push annual reactor-related uranium requirements to as high as 138,165 tU.

According to the Vienna-based International Atomic Energy Agency (IAEA) newly designed geophysical instruments and their application in uranium exploration are contributing to an increased probability of successful discoveries. Their eBook, downloadable from, highlights advances in airborne and ground geophysical techniques and methods for uranium exploration, describing modern geophysical methods and demonstrating their application with examples.

The publication is comprehensive and serves as a handy sourcebook for exploration rookies as well as veterans, students as well as professionals. The authors weigh the pros and cons of various advances in airborne and ground geophysics as they apply to uranium exploration. Along the way, they explain the basic theory of radioactivity, nuclear radiation, and interaction with matter.

An early section summarizes radioactive raw materials and the basics of peaceful nuclear energy, explaining how natural radionuclides of uranium and thorium are used in nuclear power plants to generate electricity through controlled fission which generates heat to make steam and drive turbines.

Uranium and thorium, as well as their decay products, are sources of gamma radiation and release the radioactive gas radon. Modern radiometric instruments, which detect and analyze emitted radiation, are the primary means of prospecting and evaluating radioactive raw materials and their geological mapping. The radiometrics are typically complemented by traditional geophysical methods.

Different types of radiometric detectors are explained, including ionization chambers for detecting alpha radiation, proportional counters for X-rays and gamma rays, scintillation counters, and gamma ray spectrometers. The authors point out the respective uses and limitations of these detectors.

The eBook explains how electrical and electromagnetic method scan enhance our understanding of an area’s subsurface geological setting and considers the usefulness of such methods in complementing radiometric mapping. Such methods may prove advantageous when incorporated into an exploration strategy. For example, since uranium mineralization differs little in resistivity from the host environment and since the spatial extent of an orebody is often small, it may be difficult to detect uranium by measuring resistivity or conductivity. However, electrical and electromagnetic methods can detect subsurface geological targets often associated with uranium mineralization. Examples are provided.

The report explains each technique and its respective application in uranium prospecting. In similar fashion, it sheds light on gravity methods and magnetic prospecting (both of which can be used in geological mapping in the early stages of uranium exploration), as well as seismic prospecting and well logging (borehole radiometric data are essential for calculation of uranium reserves). Remote sensing is covered as well.

Techniques for the amalgamation of diverse data sets have made a big difference as far as interpretation and presentation are concerned. The authors point out that technology has facilitated an unprecedented integration of digital geophysical data with independent vector and raster information. Three-dimensional display capabilities have become commonplace.

Finally, the report addresses the advances suggested by its title. For example, new generations of gamma ray spectrometers, some of which use advanced higher-density scintillation crystals to improve detection efficiency at higher energies, weigh under 2 kg and incorporate isotope libraries. The authors summarize the current status of electrical, electromagnetic, gravity, and magnetotelluric methods, many of which have been enhanced by GPS developments.

The eBook suggests that progress in radiometric methods is closely tied to uranium exploration. As well, certain achievements in other geophysical methods have contributed to success in uranium exploration.

A number of uranium exploration projects worldwide serve to illustrate the eBook’s technical contents, and each is presented using diagrams, charts and photos. Coverage includes the new radiometric map of Australia, unconformity-related uranium deposits in the Athabasca Basin of Saskatchewan, and the East Kimberley region of Australia.

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