By: Ndlovu Nqobile
Airborne geophysical surveys, particularly Airborne Electromagnetic (AEM) surveys, have a major role to play in mapping the subsurface and locating new mineral resources at depth and near the surface. Research and development in AEM will be driven by the demand for finding new mineral deposits. Mapping ever deeper under cover, with better resolution, will always be the aim. There are a few fronts where this challenge is taken head-on by the Spectrem Air team, with some interesting recent developments.
From an AEM system design perspective, there has been a significant focus on improving the system bandwidth, lowering base frequencies, and improving signal-to-noise ratio on both fixed-wing and helicopter-borne AEM systems.
On the data processing and interpretation front, much of the effort is going into getting more out of the acquired data in terms of a realistic geological model. This is achieved by optimising and automating the processing procedures with improved hardware and software as well as improved inversion and other interpretation techniques. Making use of as much of the available data as possible, utilising joint inversion of different geophysical and geological data sets, as well as applying AI and machine learning techniques, are all receiving a significant amount of attention.
Apart from just seeing deeper, there is also a growing need to understand and image the near surface better for accurate location and better management of groundwater as well as engineering and other environmental applications, which is also seeing continuous research and development in the AEM space.
Being a South African-based and developed technology, Spectrem Air’s focus is very much on the African Continent, with its expertise in operating in this region also providing it with a strategic advantage. It has one of the most powerful airborne systems currently available, which directly results in increased depth of penetration and enhanced geological resolution, while still maintaining the high level of detail in the near-surface geology. The system is well suited to exploring and mapping geology under cover which is typical of most African environments.