We’re not the first company to look at the Kalahari Suture Zone...
We’re not even the first company to go prospecting for copper further north either…
But there is no doubt…
At both the KSZ and the Kalahari Copper Belt, we have been at the cutting edge when it comes to using technologies in our exploration efforts.
I’m extremely proud of that.
Above all, I’m proud of the team on the ground in Botswana and here in the UK for engaging with new technology in such a committed way.
I’m convinced it’s thanks to our use of the latest technology that we could be about to make a serious breakthrough.
In particular, the deployment of magnetotellurics has been extremely useful at both projects, with the latest imagery from the KCB providing us with enough certainty about our geological models to say that further drilling is definitely warranted.
Partly, this is because the resolution on the latest set of magnetotellurics has been exceptional, with superb visibility down to depths of four kilometres.
Frankly, that far exceeded our expectations.
But more broadly, it’s because the imagery appears to show high contrast resistivity sections deep beneath the Kalahari Desert that clearly indicate areas of major folding and faulting.
That resistivity is exactly what the magnetotellurics – or, to give it its even fancier scientific name: the controlled-source audio-frequency magnetotelluric (CSAMT) method – are designed to find.
Measuring frequencies
In more understandable terms, magnetotellurics measure fluctuations in natural electric and magnetic fields over a broad range of frequencies.
These fluctuations are caused by ionosphere related solar activity in the low frequency range, and by world-wide thunderstorm activity at higher frequencies.
It’s fascinating when you start to learn more about it.
The “controlled source” in CSAMT is a specialised transmitter, which makes signals stronger and more coherent than measurement using the associated method known simply as the audio-magnetotelluric method, or AMT.
But what the CSAMT technology is showing us in the Kalahari Copper Belt isn’t just of academic interest.
The data that’s coming back could prove highly commercial too.
What the imagery seems to show is a steeply dipping geological structure or deformation zone which goes down to a depth of four kilometres.
If that’s so, it would be a highly encouraging result.
Such structures are thought to serve as pathways for fluid flow and mineral mobilisation.
Or in other words….
We may well be looking at a key component of a mineralising system.
And in addition, the deformation zone highlighted by the CSAMT also coincides both with a copper anomaly we’ve already identified in the Northern Zone of the Kalahari Copper Belt, and with a conductor we’ve identified using airborne electromagnetic surveys.
So far and it’s all so good.
The next tick in the box will be confirmation of our interpretation of the underground contact between the Nwgako Pan sediments and the shallower D’Kar lithologies.
This contact zone is recognised as a crucial control for copper and silver mineralisation in the Kalahari Copper Belt.
If drilling can confirm what the CSAMT data seems to be indicating…
The overall result will be transformational for our understanding of the Northern Zone.
We continue to move forward
As you know, drilling is already underway elsewhere on the PL082/2018 licence, targeting a different set of CSAMT data that was previously generated.
The initial focus here was justified by the presence at surface of the highest soil copper values yet recorded on the licence, and we have high hopes for this drill hole too.
But what the CSAMT data is now beginning to emphasise is that the area is likely to be rich in targets of real significance, and ones that are crying out to be tested.
So, once this first hole – KCBRC001 – is complete, we will move on deeper into this drill campaign, confident that all the data shows we’re really onto something.
Quite what that is, remains to be seen. But the time has now come where we test our geophysics against physical geology…
And I am very much looking forward to what we find.
