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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...

Snooping under Northern Ireland: The Tellus Initiative

Intensive aerial and ground data gathering by the Tellus Project produces extensive multi-use geophysical and geochemical data and collects five awards along the way

By Graham Chandler

When you have to survey 14,000 square kilometres flying straight lines 200 metres apart just 56 metres above the ground—250 over cities—you’re faced with a massive public relations exercise.

The Tellus Project had to do just that; in order to collect the most extensive airborne geotechnical dataset ever forfor Northern Ireland in the UK. The result has been well worth it: matched with two gigabytes of raw geochemical ground data, the ten gigabytes of aerial geophysical data have now been processed and are on the market. Resource companies, government departments and academics have been flocking to it.

Low-flying airplanes attract attention; and two-thirds of Northern Ireland’s population live outside major cities. Many have livestock that could be traumatized. So Tellus engaged a leading PR firm, Weber Shandwick, to handle a heads-up program.

"Public outreach before the airborne survey was substantial," recounts Michael Young of the Geological Survey of Northern Ireland (GSNI) and manager of the Tellus Project. "It included letters to registered landowners, the police, the Coast Guard, district councils as well as special interest groups." These included "horse owners, chicken farmers, deer farmers, riding schools." Posters, notices, presentations, media interviews and airtime rounded out the advance notice. A hot line was set up to field complaints as the flying progressed.

The blitz was effective. Weber Shandwick and the project garnered three PR industry awards for the campaign.

The survey had been long overdue; without it, effective land and resource management in the province would languish. Previous airborne geophysical surveys in Northern Ireland were flown back in the 1960s; since then acquisition, processing and interpretation technologies have advanced by several generations.

From the start, Tellus was designed to be more than the usual airborne geomagnetic resource surveys. "Most intensive airborne surveys worldwide are undertaken for hydrocarbons or minerals," says Young. "The Tellus airborne specifications are equally appropriate for baseline environmental surveys."

The data were collected between 2004 and 2007, with the flight segment from July 2005 to May 2006. Managed by GSNI, the project had logistical input from the British and Finnish Geological Surveys who jointly operated the survey airplane, a De Havilland Twin Otter equipped with two magnetometers, a four-frequency electromagnetic system and a 256-channel gamma-ray spectrometer.

The low-level flight plan gathered magnetic, electromagnetic and radiometric data flying alternating parallel legs in opposite headings of 165° and 345°. For the ground program, multi-element geochemical data were obtained from stream water, sediments and soils. Soils were analyzed for organic and inorganic compounds.

On board the Twin Otter, magnetic data went through a MAGCOR software package, which applied a diurnal and several other corrections. The data were then imported into Geosoft Oasis montaj which corrected for all remaining errors such as spikes and VHF communications interference, then used MAGLEV for data leveling. Geosoft was also used to process the Caesium-137 radiometric data from the spectrometer.

All of which attracted yet another award. "Our results with Geosoft helped Tellus win the 2008 Innovation & Best Practice award from the UK Association for Geographic Information," says Young.

There’s a global warming aspect to the Tellus project. As soils are a significant store of carbon, integrating radiometric and soil survey data can improve estimates of soil organic carbon. "BGS soil scientists are using geostatistics to combine Tellus airborne radiometric potassium data with ground measurements of organic carbon to improve our estimation of carbon stocks in soils," says Young. He adds that reporting soil carbon stock is a requirement in the European program to establish national carbon stock levels in order to manage carbon sequestration.

Another environmental aspect was to examine radioactivity over the province. The Tellus project extrapolated radon levels from both the geochemical and the geophysical data, as there is strong correlation between uranium in soil samples and uranium measured radiometrically. The Palaeogene intrusives of the Mourne Mountains are the most radioactive rocks in Northern Ireland, so pulling together this dataset presents an opportunity to inform the public of the risks of radon exposure.

Which is important. "Radon is the second biggest cause of lung cancer and is thought to account for 1,100 deaths in the UK annually," says Young. He says they used multivariate geostatistical analysis to improve estimates of radon risk "We have been able to produce a more scientific risk map; previous maps only involved contouring in-house radon measurements, which are very sparse." Indeed, the Journal of Environmental Radioactivity last October reported a program examining the use of Tellus project airborne gamma-ray spectrometer and soil geochemical data to supplement in-house measurements and predict the probability of houses in Northern Ireland having high indoor radon concentrations.

"We also mapped Caesium-137, a wholly artificial isotope produced by nuclear weapons testing and the Chernobyl 1986 accident," says Young. "Current levels are low but we see clear associations with rainfall patterns and elevation." He says these levels provide a useful baseline dataset for mapping any future incidents.

An October 2007 story in the Belfast Telegraph even reported Tellus had discovered an underground hot springs near Larne that "could have the potential to provide heat and electricity for several of Northern Ireland’s towns and cities." It was reported that hot rocks 3,000 metres under the surface had heated the natural groundwater at the site to about 90 degrees C, and private sector companies could soon tap into this natural energy source. 

But Young says that was a bit optimistic. "The Larne thermal anomaly was discovered by previous drilling," he says. He explains the Tellus data did provide improved information to support structural mapping in this area but couldn’t directly detect geothermal resources. However further geophysics and drilling planned for the next phase of Tellus this year will further elucidate "this low-enthalpy geothermal resource," he says.

No alarming geohazards were detected by the survey. "The most striking results were the magnetic images and the great detail shown on dykes, faults and intrusives," says Young. "All of which will significantly improve our geological map revisions."

However some toxic findings had pause for concern. "The main toxic element anomalies are high nickel and chromium over the Antrim lavas, which significantly exceed the Soil Guideline Values (SGVs) for residential development," says Young. "And high arsenic values are associated with mineralized areas in the west and south." He says high values of nickel and chromium in the Belfast urban surveys are due to the naturally high soil levels. Other elements in the urban results like arsenic and lead, due to past industrial activity, were also found to be higher than the SGVs at isolated spots. But, "on the whole, says Young, "Belfast appears significantly cleaner than other UK industrial cities surveyed."

The digital data are now available in along-line or gridded formats, according to the GSNI website. Who have been the biggest customers so far? "Mining companies," says Young. But academia isn’t far behind. "Some 25 university researchers and MSc or PhD students have licensed the data for various projects," he says. "Geochemistry of soils, agriculture, highway planning, roadstone mapping, peat mapping, water catchment chemistry, geostatistics, etc." He says local planners have been relatively slow to take up the data but "we expect these data to provide this sector with essential environmental baseline data in the future." Of government departments, the largest user may be the Department of the Environment where the geochemical baseline will be used to meet several EU directives.

Commercial use of the data blooms. Three companies are exploring for potential natural gas storage in Permian salt beds. Resource corporations interested in gold and base metals have shown much interest in the new data, says Young. "Gold shows are widespread—the Tellus geochemical surveys have detected numerous anomalies in soils and stream sediments in rocks of the Neoproterozoic Dalradian Supergroup," he says. "Companies active here include Dalradian Gold and Toronto-based Galantas Gold Corporation’s Omagh Minerals." And prominent gold anomalies detected in the Lower Palaeozoic rocks of the southeast across the border from the Republic of Ireland’s million-ounce deposit at Contibret have sparked some excitement from Conroy Diamonds and Gold Ltd, which hold several licenses in Northern Ireland, he says. Young adds that the world’s third largest platinum producer, Lonmin plc, is pleased about clusters of platinum anomalies overlying the Palaeogene Antrim lavas too.

"Since the results were released the area of land licensed for [mining exploration] in Northern Ireland has increased from 15% to 70%," says Young, "and £15 million has been committed in exploration license agreements." Recognizing the country that has done most to promote mineral development, along came yet another award: Northern Ireland and the Tellus project were presented with the Mining Journal’s 2008 Outstanding Achievement Award.

All these awards don’t mean Tellus will sit back on its laurels. There’s more to do with the data. The Northern Ireland government has allocated £2 million for further follow up. Young says it will be spent on things like developing web-accessible indexes and value-added reports and products, 3D regional and urban geological modeling and a 3D visualization suite. And the airborne data, which have so far been interpreted only at a regional scale, will be interpreted at the 1:50,000 scale and used to revise the 1:50,000 geological maps and to map environmental effects in detail. This is to include prospectivity analysis and mapping as well as targeted research on specific mineralization. Research in geochemistry for agriculture and survey and basin interpretation for geothermal resources will round out the future of this intensive data-gathering exercise.