South African airborne geophysics technology provider Spectrem Air plans to reintroduce the application of its airborne electromagnetic (AEM) platform – the SPECTREMPLUS system – to the mineral and groundwater exploration industry in West Africa.

This continually evolving platform entails being able to see deeper, as the company currently has the highest dipole moment.

“The dipole moment is a measure to determine the power of an AEM system and its ability to resolve deep targets and structures while using its high-resolution ability to better resolve shallow structures. We are always researching methods to improve our processing and interpretation capabilities,” says Spectrem Air geophysics manager Brad Pitts.

Further, Spectrem Air focuses on geological mapping and exploration using airborne technology.

Pitts notes that the mainstream geophysical exploration techniques of airborne or ground-magnetic, radiometric and electrical techniques are available in West Africa, provided either by local service providers or consulting companies operating in the region. However, AEM surveys are the domain of specialist service providers.

The company’s technology can also be employed on a regional or detailed high-resolution scale and is not hampered by the lack of ground access in inhospitable environments because it is an airborne technique.

Over the years, Spectrem Air has conducted several surveys in West Africa. One of the main benefits of deploying the AEM technology is the SPECTREMPLUS system providing good geological information under cover, says Pitts.

Meanwhile, the company has assisted a client in reinterpreting some of its existing AEM data, which has enabled the client to improve on its models for mineral deposit formation, especially with the identification of structures, thereby controlling the mineralisation in its prospects and on its targeting ability.

The benefits of Spectrem Air products and services are twofold, says Pitts.

Firstly, they can assist with direct exploration efforts through target identification, which feeds directly into the mine identification and planning process.

Secondly, they can identify and map geological structures, such as faults, dykes, folding, depth to basement and overburden thickness, with the client, provided that the AEM data, coupled with other data sets, is correctly applied and interpreted.

“This information can be important, not only for safety, but also to delineate groundwater aquifers and channels, as well as paleochannels.”

State of Mining

“Mining in West Africa is facing an interesting upturn, with several major, midtier and junior companies exploring for different commodities,” says Pitts.

Gold exploration in several countries is gaining momentum. This also includes a number of deposits of various deposition styles, sizes, grades and economic viability, which have been exploited by formal and artisanal miners.

However, Pitts highlights the lack of infrastructure as a perennial challenge, which is hampering development in some regions. Corporate tax and royalty rates vary across the region and are not always competitive, as opposed to other mining jurisdictions, he adds.

“Portions of West Africa have recently faced an economic downturn; however, there appears to be increasing stability and a real commitment to improving the legislative and commercial environments in a number of countries. “This is supported by the relative percentage of exploration spend that West Africa is enjoying, compared with other mining regions in Africa.”

Pitts says many of the challenges can be addressed by providing stable political and economic environments.

Further, continued mineral discoveries – coupled with the responsible exploitation of economically viable targets – will attract interest and investment in the region, as well as continued acquisition and the dissemination of exploration data by governments, he concludes.