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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...

Academics and industry team up for marine UXO surveys

Company borne out of an academic collaboration benefits both students and industry doing offshore UXO surveys in the North and Baltic Seas.

by Graham Chandler on March 8, 2013 applied

[Click to enlarge]

Cleaned, IGRF corrected and detrended data, using an upward continuation filter. The data have been recorded with a single magnetometer and a profile spacing of 80 m. The profiles are oriented N-S.

Two merging lines of strong anomalies can be seen in the gridded data. The anomalies match with the location of a filled glacial channel system, which was detected by means of reflection seismics.


[Click to enlarge]

Cleaned, IGRF corrected and leveled magnetic data, recorded with a single magnetometer and a profile spacing of 300 m. The profiles are oriented NE-SW. In the gridded data a line of strong anomalies can be seen above a buried pipeline, which runs from NW to SE.

When the volume of offshore UXO surveys in the Baltic and North Seas began to expand with the growth of offshore wind farms in the late 2000s, a professor at the University of Bremen’s MARUM (Center for Marine Environmental Sciences), Dr Tobias Moerz, decided to spin off an independent company. The new company, Geo-Engineering.org GmbH, was formed in February 2009 and it enjoys the benefits of close contact and association with the university and its scientific expertise within MARUM and the Department of Geosciences.

Starting in 2006, the university and MARUM carried out industry-related geotechnical and geophysical surveys under the working group known as Marine Ingenieurgeologie, headed by Moerz. As volumes quickly increased, the rapidly growing workload created other concerns. “The increasing risks and liability requirements related to vessel charter for geophysical surveys and exploration of offshore wind farms necessitated the creation of a legally independent company,“ says Bastian Kuehl who works in project development and applied geophysics for Geo-Engineering. He adds that the new company has signed a co-operation agreement with the university and MARUM.

Johannes Brock, who is in the same department as Kuehl, says that since its founding the company has worked closely with offshore windpark developers in Germany. “The schedules of those developments are very strictly prescribed in documents by the German authorities,” he says.

The UXO surveys are prescribed by Germany’s Federal Maritime and Hydrographic Agency in its 2008 publication Standard Ground Investigations for Offshore Wind Farms. “UXO surveys are required and someone has to do them,” says Brock. “There are not many companies in Germany who are competing in this business, so we took our chances.”

Geo-Engineering maintains its strong ties with the University of Bremen and works closely with university personnel. That shows in the makeup of its staff, most of whom were recruited from university alumni after graduation, and in some cases even before. That strategy continues to be a recruiting advantage for the company. “We offer young innovative specialists in geology, geotechnics and geophysics the opportunity to use their skills directly in the industry,” Brock says.

It’s a win-win. The students are highly motivated to do applied fieldwork whereas Geo-Engineering benefits from their educated knowledge of the latest trends and technologies in the field. At the same time, the students can earn good money during their studies and secure valuable experience for their future careers. For example, a lot of offshore work is done in the summer between July and September, which happens to be the semester break for German universities. Some students stay on throughout the year. Many like the exposure to hands-on research in this field of ocean sciences, as it helps them make decisions about their career directions.Kuehl notes that for those students who wish to use project data for a bachelor‘s or master‘s thesis, the university and industry can permit them to use recorded data, usually with the proviso of deleting proprietary information such as geographic co-ordinates.

The university’s scientific expertise is made available as a result of the association between MARUM and the Department of Geosciences. For example, MARUM maintains a repository of core from international deep-sea drilling as well as advanced technology for ocean exploration. Examples of the latter include a deep-sea drill rig, remotely operated vehicles, and an autonomous underwater vehicle. All of which could be useful to Geo-Engineering in its UXO surveys.

Kuehl cites flexibility as one of Geo-Engineering’s competitive advantages. “Since our company is not very big, our staff in the fields of civil engineering, geology, engineering geology and geophysics work closely together,” he says. “In this way, we are able to find unconventional solutions for our customers.”

Geo-Engineering customers include clients who require offshore UXO surveys to support wind farm installations. Generally, these clients must first carry out (or contract out) the required preliminary research to ascertain where potential seabed targets might lie. The research might entail searching military archives and libraries. Armed with these data, the client will then engage an offshore survey contractor such as Geo-Engineering.

This is where the students’ hands-on experience begins. Geo-Engineering takes one or two students on board who are able to gain valuable practical field experience right from the start. They take part in the initial magnetic gradiometer and side-scan survey, wherein the company uses steel survey boats with the gradiometer on a cable about three to five times longer than the boat. “For the cleaning survey, we use larger boats with the capability to host working class ROVs (remotely operated vehicles),” says Brock. “For near-shore or in-shore work, we use our own 7-metre-long, gfk [glass-fibre-reinforced plastic survey boat [which is non-magnetic].”

Students also have the opportunity to help with hardware and data acquisition equipment. “We use two GEOMETRICS G-882 Cesium Magnetometers in a transverse gradiometer configuration,” explains Brock. From the measured total field data, the quasi-analytic signal (QAS) is calculated, a common technique for interpretation of magnetic data. Then a dipole modeling is calculated using the two total field data records per profile line. “This method guarantees the best possible location information, especially for small objects which are located between two profile lines,“ notes the company’s brochure.

Brock notes that “for the preliminary geophysical survey, we generally use our gradiometer together with a side-scan (Cmax CM2) on high-resolution settings for the visual verification of the target”, adding that seismic pingers are seldom used owing to their poor resolution. Other offshore techniques such as multi-beam bathymetry are in most cases not necessary.

Students observe optimum setups for surveys (for example, the distance between the two magnetometers, which is normally one metre). They also learn how to determine line spacing. “The line spacing depends on the requirements of the customer,” says Kuehl, “for example, the size of the objects which we want to detect. To locate small objects we recommend a line spacing of 10-20 m.”

It’s not only offshore where students gain useful experience—they participate in data processing too.

“For data processing, interpretation and imaging, we use Geosoft’s Oasis montaj together with the extensions UX-Detect, UX-Process and UX-Analyze,” says Kuehl. “This package is quite a complete and powerful tool. We also look forward to the implementation of the TVG workflow, which will enable us to use two total field records per profile line for a dipole inversion. For sparse profile lines, this can be an advantage against grid-based modeling.”

The surveys have their share of challenges.

“The biggest challenge is the diversity of possible UXO in the North and Baltic Seas,” says Brock. “The identification of a target after 70 years in salty water and sediment is most important for risk minimization.”

Indeed, experts estimate that ten percent of all military ordnance deployed during the Second World War has failed to explode. Danger still lurks in live naval mines from defensive barrage minefields not fully cleared at war’s end, as well as in torpedoes, land-to-sea artillery, air-delivered bombs, dumped munitions, and sunken ships.

Brock reckons this drives a need for more experts in the field. “Not only is the technical side a big challenge but it is also essential to build up a network of specialists for UXO Identification”,  he says.

Meanwhile the rapid growth of offshore wind farms continues. The European Wind Energy Association reports that installed wind generation capacity in the European Union has increased by 523 megawatts to exceed 100 gigawatts for the first time. Close to a quarter of that capacity is in Germany. The EWEA says there is enough European offshore wind farm potential to power Europe seven times over.

More and more offshore areas are being scouted for wind farms. “Many of these sites contain the theoretical risks of UXO, especially in the North and Baltic Seas,” says Brock. “There is a lot of work to do out there.”

And along with it, a lot of potential experience for students interested in UXO surveying.

Related Articles:

Introduction of UXO Marine software
Clearing the way for winds of change
AUV Magnetometers a leap forward in seabed surveys


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