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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...

At home in the field

by Graham Chandler on December 10, 2013 community

The AfricaArray field school is helping to prepare geoscience students for work in Africa and the rest of the world. Shown above: students use a Geometrics Walkmag to collect ground magnetic data.



Students are introduced to five different geophysical techniques, software, geology and safety. They use forward modelling software and cost estimates to design a survey and work flow.

Launched in 2004, the AfricaArray program is enabling students in Africa and America to develop their field experience and share valuable knowledge about the geosciences.

AfricaArray was founded by Penn State, the University of the Witwatersrand (Wits), and South Africa’s Council for Geoscience. The program is committed to supporting the geosciences in Africa by funding postgraduate studies, facilitating student exchange between the two universities, setting up a pan-African research “seismic network”, as well as funding and supporting an annual field school.

The field school, which Geosoft has supported for more than five years, takes on between 20 and 25 students from Africa and the U.S. each summer. Included are fourth-year Wits students, for whom field school work is compulsory. Other African students include postgraduate students, lecturers, and geological survey employees.

African students have been sponsored by the Society of Exploration Geophysicists (SEG) for eight years, the United Nations Educational, Scientific and Cultural Organization (UNESCO) and the International Union of Geological Sciences (IUGS), while U.S. students have been sponsored by the Opportunities for Enhancing Diversity in the Geosciences program of the National Science Foundation (NSF). The NSF students are selected by Penn State as part of an REU program (Research Experience for Undergraduates) on merit from under-represented groups in the geosciences. They also receive pre- and post-field school training at Penn State.

The AfricaArray program runs for three weeks at Wits, explains Stephanie Enslin, senior instructor. In the first week, Wits graduate students and staff give lectures which introduce undergraduates to five different geophysical techniques, software, geology and safety. Another first-week task is to help students prepare for the job market. This involves creating a real-world “request for bid,” as if the students were submitting a bid to a mining company to carry out a geophysical survey. They use forward modelling software and cost estimates to design a survey and work flow.

The second week takes place in the field at South Africa’s Bushveld Complex, a large igneous intrusion with the largest platinum reserves in the world. This year, Enslin and fellow students went to the eastern part of the Complex and carried out a survey where sponsor Anglo Platinum hopes to develop open-cast mining of the Merensky Reef. Students were divided into groups which rotated through different geophysical methods each day. Graduate students and staff supervised the work, which included reflection and refraction seismics, resistivity, gravity and differential GPS, magnetics, EM, and ground-penetrating radar. In the evening, the day’s data were downloaded and processed, and at 7:30 the following morning the results were presented.

Says Enslin: “Students also spend time looking at borehole cores, measuring densities and susceptibilities, so that they can have realistic values for the geological models they create in the third week. We were lucky enough this year to visit a new nearby open-cast mine; which gave the students some perspective as to what conditions are actually like 20 metres under the surface, all the way down to bedrock.”

Susan Webb, director, and Stephanie Enslin, senior instructor with the the AfricaArray field school test a new Scintrex CG5 Gravity Meter.



[Click to enlarge]

Geosoft software is used during field work to create geological and aeromagnetic maps overlain with the grid on which the students are working.

Geosoft software is used during this second week to create geological and aeromagnetic maps overlain with the grid on which the students are working. This helps to keep track of where they have surveyed and to make sure there is overlap between the geophysical methods used.

The field location is important in AfricaArray. In the Bushveld, for example, students are in a real mining environment working on a real project. Dykes in the area cause “loss of ground,” and variations in overburden directly affect the cost and safety of an open-cast project. “The mine actually selects the region in which we work,” explains Susan Webb, director of the field school, “with the caveat that the goal is to train students, not do a consulting job. The mine obviously gets the data; and we are able to work out of an exploration camp.” 

The third week is back at Wits, where students choose geophysical methods with which to work. Each student in each group works on a different method. Then, together, they organize and process the data. “This is where Geosoft has been most useful,” says Enslin. “Students import their data into databases which are used to display profile data. They also use Geosoft to create grids and maps which they can then overlie the profile data on to. These grids are essential when it comes to correlating features detected by different techniques, as well as correlating with the geology and terrain maps.”

Webb says the loss-of-ground factor provides an excellent opportunity for students to fully utilize the Geosoft platform. “Geosoft provides an integrated toolset that allows the students to understand the importance of planning through to final interpretation. They can see where the dykes are and they can also see how the ground magnetic data radically improve the imaging.” In short, the capabilities help the students visualize the data in the field context.

Students then model the data, correlating the different data sets as well as borehole data to create as accurate a geological model as possible.

On the Friday of that third and final week, the groups present their interpretation. The Wits students go on to submit individual reports combining all these data while each of the U.S. students presents on a different method back home.

Webb says the program is essentially two-tier: “The participating students learn about planning and about collecting, interpreting and integrating the data, while the graduate student instructors learn about software, maintaining equipment, logistics, data quality (for example, making sure the data are of consistent quality across five different groups), and how to interact with people from divergent backgrounds with varying understandings of geophysics.” 

Students take what they learn in the field and apply it to their work back home. As an example, Webb cites one of this past year’s students who has equipment at his home institution in Cameroon and is now setting up a field school for a ground water program he’ll be teaching. Another example is Ester Mutari, who has started her own field school in her native Kenya.

Notes Webb: “Ideal candidates [for AfricaArray] are junior faculty members in departments that have access to equipment but limited field experience.”

The resounding success of the field school is echoed in the response of this year’s participants:

“We managed to get a general idea of what the pyroxenite package, which includes the Bastard and Merensky Reefs, looks like below the overburden and also where it’s situated,” says Kirsten Stephens, a fourth-year honour’s students in the Wits geophysics program. She speaks enthusiastically about the field school program in general: “It was great to have so many different countries and cultures coming together to learn about geophysics. I also made valuable connections with people for future research opportunities.”

Stephens notes that Geosoft proved especially helpful in the survey work. “We were able to display results, say from magnetics and gravity, and then overlay those results onto different images to aid with interpretation. Simply overlaying the gravity over an image of the field area with the proposed outcrop of the Merensky Reef helped us piece the whole geological model together.”

For fellow field-school student Henry Mukasa, a graduate geologist from Makerere University in Kampala, Uganda, the school was “that single opportunity that would help me pursue my ambitions.” His experience with AfricaArray will certainly add a new dimension to his current work as a junior geologist with Auranda Minerals in Entebbe. “It was my first time putting geophysics theory into practice, and I was given the opportunity to handle and control most of the field data. For me, this was like a dream come true.”

Sponsors of this initiative include: Society of Exploration Geophysicists, International Union of Geological Sciences, United Nations Educational, Scientific and Cultural Organization, Council for Scientific and Industrial, Research, TGS, Anglo American, Anglo American Platinum Limited, Geosoft Inc., Dr. D.H. Loke, GEOTOMO Software, Professor Gordon Cooper, Head of Geophysics, University of the, Witwatersrand, Geometrics, National Research Foundation, National Science Foundation Council for Geoscience, theUniversity of the Witwatersrand and the Pennsylvania State University.


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