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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

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...

February 10, 2016

Cameco's new uranium discovery revealed

Canada's top uranium producer has a significant new discovery nearby to one of its largest existing mines...

February 9, 2016

NexGen Drills Most Intense Mineralization to Date at Arrow

NexGen announces further results from its on-going six rig 30,000 m winter 2016 drill program on its 100% owned Rook I Property in the Athabasca Basin, Saskatchewan...

February 9, 2016

Rio Tinto scales up its big data ambitions

Rio Tinto is opening its "vast troves" of exploration data to junior explorers in the hopes they will help sift for opportunities and supply ideas and labour...

February 8, 2016

Online portal improves access to geoscience data from Africa

The Botswana Geoscience Institute is launching a Geoscience Portal...

February 8, 2016

5 Best Minerals & Fossils To Buy With Your IRS Tax Refund

You just got your IRS tax refund and now you're presented with some cash to go out and buy one of a kind minerals and fossils from your local...

February 5, 2016

World's largest offshore windfarm to be built off Yorkshire coast

Dong Energy makes final investment decision on 1.2-gigawatt project that will power more than a million UK homes...

February 2, 2016

World's top 10 rookie gold mines

These high-grade mines will soon start competing with gold mining's industry leaders ...

January 25, 2016

Exxon Mobil Corp's defiant outlook predicts Canadian and Venezuelan oilsands output will 'quadruple' over next 24 years

In sharp contrast to the grim medium-term prognosis for the Canadian oilsands, Exxon Mobil Corp. is predicting sunnier times for bitumen in the decades ahead...

January 23, 2016

Magnetic Survey Keeps Cost Down

At a contaminated furniture factory site in North Carolina, a reconnaissance magnetic survey was conducted toward the end of a Phase 2 investigation ...

What Lies Beneath: Detecting Bombs Under the Earth's Surface

Paul Lima

With the growth in global population, land for housing, business and recreation is in great demand. However, land that seems available might not be suitable for human use if it has served as a battleground in warfare or if the military has used it for practice ranges or the disposal and destruction of munitions. Land mines and unexploded ordnance (UXO) contaminate more than 83 countries. When munitions are fired but don't explode or only partially explode, they are categorized as UXO. Battlegrounds in the First and Second World Wars are a typical example of UXO fields. UXO can also be found in regions of developing nations in the 20th and 21st centuries where civil or proxy wars have been played out (such as occurred in the Cold War). These fields are scattered around the globe. In the U.S., more than 2,000 closed or transferred military ranges are believed to contain UXO. Before land with buried UXO can be reclaimed for housing or other projects, the UXO must be found and removed.

The UXO Detection Challenge

Locating and removing UXO can be complicated, time-consuming and costly. In Europe, there is growing advocacy for UXO and mine clearance, with stronger partnerships emerging between UN, community and government agencies to set out plans for UXO removal. Standard UXO detection techniques in Europe generally make use of traditional grid-pattern borehole drilling. In North America, the civil engineering arm of the military is in charge of UXO clearance. UXO teams in North America, working under guidelines set by the U.S. Army Corps of Engineers (USACE), collect and analyze data for UXO removal with the aid of geophysical techniques and specialized software.

"If we had to remove bombs from flat homogeneous areas such as sand bars, we could easily detect the UXO with geophysical sensors and they would stick out like sore thumbs, but that's seldom the case," says Elizabeth Baranyi, Earth Sciences application programmer with Geosoft.

In areas that are rough or wooded or where the soil is magnetic or covered with lava flow that has a high iron content, sensor readings become busy, making it difficult to distinguish between geological and UXO signals. Other buried objects of similar size, such as a metallic grid, can further complicate the interpretation of data. The discrimination between UXO and non-UXO is a cost concern that is a subject of ongoing research.

Precision and data quality is critical in UXO surveys; all external factors must be minimized as they can interfere with the reading of UXO signals. Examples include steel-toed boots, jangling keys, flopping cables, and even inconsistent walking speeds.

Before the introduction of software, contractors used instrumentation to locate UXO and dig where they found peak readings. This method was knows as "Mag and Flag." "However, the peak isn't necessarily right above the UXO," says Baranyi. "It depends on the size, shape, depth and dip angle of the UXO, and, in the case of magnetic surveys, the magnetic field of the earth. You can dig at the peak and miss the target by a few centimeters, or you might spend a lot of time digging for objects only to find they aren't UXOs." The aim is to improve the quality and the discrimination methodology of the UXO survey data in order to save time and money while ensuring confidence in the outcome.

Since there could be a large number of ordnances in a small area, or a few deadly ones spread over a large area, trying to pinpoint UXO locations is like looking for needles in a haystack – or, as in geological exploration, looking for a rare mineral that might or might not be present. But the process is getting easier, thanks to advanced geophysical techniques, computer-aided analysis, and 3D modeling.

Initial Planning

Exploring for UXO typically starts with initial geophysical planning. A geophysical investigation system capable of pinpointing buried UXO must have four fully integrated components:
  • Personnel experienced in the theoretical and practical aspects of detecting UXO and discriminating between UXO and non-UXO. The selection and utilization of geophysical equipment require qualified, experienced individuals.
  • Geophysical instruments that are well-suited to detecting buried UXO, taking into account site-specific factors such as the type and depth of the target UXO, terrain, vegetation, and geologic and cultural settings.
  • Navigational accuracy and precision, that is, the ability to locate, within the centimeter range, the geophysical data in relation to other known points.
  • Procedures for analyzing and interpreting geophysical data generated by geophysical instruments.
If any of the above four components are lacking, the overall geophysical system will not be able to locate UXO precisely. It's important to plan and integrate all aspects of a geophysical investigation carefully and not start fieldwork prematurely.

Geophysical Techniques

Geophysical investigations performed at sites that may contain ordnances can be divided into three categories:
  • Geophysical sampling performed at representative portions of a site to characterize a larger area. The objective here is to characterize the distribution, type and condition of UXO across a site in a way that is both economic and accurate.
  • Geophysical mapping performed across an entire area suspected of containing UXO. The objective is to locate all detectable UXO that meet pre-determined criteria such as type, size, composition and depth.
  • Geophysical interrogation performed at specific locations or small sites to obtain additional target information beyond that gathered by initial investigations. Although slow and expensive, this technique can yield important information about the size, depth, composition and configuration of individual targets or target clusters.
Overall, the objective of such geophysical investigations is to locate UXO while minimizing the number of non-UXO geophysical anomalies. Since unearthing buried munitions is expensive, the data collected must be scrutinized carefully, and computer software is used to help with the analysis and for quality control.

Software for UXO

UXO investigations require the use of digital geophysical mapping software and depend on quality field data. The software is used to minimize the risk of inconsistent data and faulty decision-making. For instance, data filtering algorithms can level and smooth data, eliminate background noise, and enhance geophysical real anomalies that have UXO-like signatures. Software can also help convert high volumes of geoscientific data into knowledge that supports accurate UXO mapping and target detection and narrows selections to a final target list.

As part of its mandate, the U.S. Army Engineer Research and Development Center (ERDC) has been funding the development of technologies for the detection and discrimination of UXO in an effort to improve the process.

One of these initiatives, a co-operative agreement between Geosoft and the USACE, Huntsville Center, has resulted in industry-standard tools to boost efficiency and accuracy in UXO investigations. These UXO Quality Control and Quality Assurance (QAQC) software tools, developed within Geosoft's Oasis montaj platform, are being used at UXO sites around the world to improve data consistency and detection methods.

Beyond quality control, software is essential to UXO project management insofar as it allows work to be recorded, both for review and future audit. With all UXO investigations, it's necessary to demonstrate that the site was cleaned up as well as possible and that everything that was conceivably detectable – based on available scientific and technical capabilities – was in fact detected.

In short, software and quality control measures are essential both for the interpretation of data and the creation of standardized analytical processes. With advancing techniques and the right software, it's possible to manage UXO projects effectively, saving limbs and lives in the process.