Aim-listed Power Metal Resources has confirmed that its Molopo Farms Complex (MFC), in southwestern Botswana, has the required geological ingredients to host a significant nickel deposit, as found in other mafic and ultramafic belts elsewhere around the world.

In an exploration update from MFC, published on October 6, Power Metal noted that the target area T1-14 had demonstrated the highest potential owing to the strength of the super conductor originally identified.

The company is targeting a district-scale nickel and platinum group element (PGE) discovery at MFC.

“The work focussed on target area T1-14 has delivered a superior database and is now the highest priority conductor target, based on all the evidence we have gathered thus far.

“This exploration work, which is currently focussed on target area T1-14, is being conducted in parallel with our ongoing engagement with third parties with regard to commercial avenues for Molopo Farms,” Power Metal Resources CEO Sean Wade said.

The previously conducted airborne electromagnetic (EM) geophysics surveys flown in 2018, followed up with ground moving loop electromagnetic (MLEM) geophysics surveys completed in 2022, led to the identification of targets subsequently drilled during the 2022/23 campaign.

Drillhole DDH1-14B from the 2022/23 drill campaign did not intersect the modelled superconductor. This led the company to engage a geophysicist to complete inversions of widely spaced audio-frequency magnetotelluric (AMT) survey results from 2020 that were completed over target area T1-14. AMT technology can measure a wider range of conductivities compared to airborne and/or ground EM and to a greater depth.

Significantly, this work led to the identification of two distinct conductors at target area T1-14, compared to one moderately dipping conductor identified by the MLEM, including a very strong steeply dipping multi-kilometre-long conductor which is co-incident with the keel of the feeder zone intrusion.

Power Metal said this conductor has the potential to host massive sulphide mineralisation and thus had been deemed a high-priority exploration target, which had never been drill tested to date.

The second conductor identified is relatively flat-lying and determined to be sedimentary in origin which led to the false targeting during the previous drilling campaign.

The company is working with its technical consultants regarding the implementation of a drill programme at target area T1-14 to test this newly modelled steeply dipping conductor.

“Historical exploration work at MFC has been multi-year, extensive and absolutely necessary in order to narrow down key targets for exploration drilling within a very large licence footprint. In exploration, geophysics alone is never enough and drilling is always necessary to firm up the geological model and confirm economic deposits.

“As drilling is undertaken, the additional data gathered can, with other exploration techniques, provide a step-change enhancement of the technical understanding of a project and its potential,” Wade said.
 
EM surveys and drilling have proven the presence of a funnel shaped ultramafic intrusion within the northeastern part of the MFC. This dyke-like intrusion can be traced on magnetic maps for at least 20 km towards the southwest where it is seen to merge with a thick sequence of layered ultramafic rocks.

The intrusion follows a well-established northeast-southwest fault zone and is interpreted to be the geological feeder zone to the MFC, which Power Metal said was an important target when searching for magmatic nickel- and PGE-rich sulphides.

Such feeder zones are known to be potential loci of sulphide mineralisation associated with the intrusion, for example at Voisey's Bay, in Canada, or Uitkomst, on the eastern limb of South Africa’s Bushveld Complex, which is an age-equivalent unit to the MFC.

Inversions of a historical AMT survey completed over target area T-14 in 2020 in the region of the known feeder zone have identified a very strong steeply dipping conductor co-incident with the keel of the intrusion.

The base, or keel, of such a feeder intrusion may well be the site of massive sulphide mineralisation and is thus a priority exploration target, which has never been drill tested before.

As a result, drilling plans are currently being developed by Power Metal’s technical team in order to optimally test this target.

Given the success of the AMT technology and inversions thereof to decipher between multiple conductors at target area T1-14, an airborne AMT survey is also being considered to further image other target areas which have only been investigated by airborne or ground EM to date, Power Metal said.

DISCUSSION ON FUTURE MFC EXPLORATION

As the demand for nickel continued to increase, exploration for magmatic sulphide deposits within mafic/ultramafic complexes would continue to be of significant interest to junior and major mining companies, Power Metals said.
 
The company noted that, compared with many other significant mafic provinces, the MFC was comparatively underexplored, likely as a result of the extensive Kalahari sand cover. However, based on the information acquired, Power Metal now believed it was evident that the MFC had the required ingredients which could allow for the formation of a magmatic sulphide deposit.
 
To that end, the company said one of the major challenges of exploration within the MFC was the fact that the mafic-ultramafic rocks had intruded into Transvaal Supergroup sediments, many of which are known to be sedimentary conductors.
 
While the presence of these iron-rich sedimentary rocks is one of the key ingredients required in order to form primary magmatic nickel sulphides, the presence of multiple conductors can make drill targeting difficult, especially considering the lack of outcrop exposure within the MFC, Power Metal said.

Owing to these considerations, the company said, significant further exploration was warranted in the future at MFC.