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Kavango Resources #KAV – New TDEM Loop Designs for the B1 Target Area
Following completion of Hole KSZDD002 to target depth of 650m (announced 28 February), Kavango Resources plc (LSE:KAV) has redesignated the B1 Conductor as the “B1 Target Area”.
The B1 Target Area is located above the Great Red Spot (the “GRS”), a large-scale 5km by 8km coincident magnetic and gravity anomaly in the northern (Hukuntsi) section of the Kalahari Suture Zone (“KSZ”).
The B1 Target Area has been re-modelled and contains two conductor targets (“the Targets”), which the Company believes are prospective for nickel/copper (Ni/Cu) sulphides.
– Target B1-1 is a shallowly dipping modelled plate, with a conductance of 16,000 Siemens. This level of conductance is consistent with possible Ni/Cu massive sulphides
– Target B1-2 is a vertically dipping modelled plate with a conductance of 2,500 Siemens, and is consistent with the presence of possible Ni/Cu net textured sulphides
The existence of the two Targets has been confirmed by a Downhole Electromagnetic (“DHEM”) survey of borehole KSZDD002, and the modelling of both the DHEM and Surface TDEM in tandem.
An intrusive Karoo gabbro was intersected at the modelled target depth of Target B1-2 in drillhole KSZDD002, which indicates the right host rock environment for Kavango’s exploration model. The Targets conform to Kavango’s idealised model for a potential massive sulphide body in a shallow dipping Karoo gabbro sill, associated with a possible Karoo gabbro vertical feeder dyke containing net textured sulphides. The Company plans to drill test the Targets with two boreholes.
To this end, Kavango has now finalised designs for new Surface Time Domain Electromagnetic surveys (“Surface TDEM”) and subsurface DHEM surveys, using two large 1km x 1km electromagnetic loops. These two loops are designed to ‘null couple’ separately with each of the two Targets, to test rigorously the new modelled conductive plates. The surveys will aim to gather data to refine the size, shape, depth and orientation of the Targets. These data will then be modelled to finalise the drill collar locations.
Kavango is in discussion with Spectral Geophysics Pty to conduct the TDEM and DHEM surveys over the B1 Target Area as soon as a team and equipment become available.
In addition to this, work is ongoing to conduct a much more extensive TDEM campaign across the Hukuntsi area of the KSZ, including (but not limited to) the GRS and the “30km Strike” target zone (announced 23 November 2021). Based on initial results from its recent drill campaign, the Company’s objective is to build an inventory of high conductance targets for future exploration and drilling.
Ben Turney, Chief Executive Officer of Kavango Resources, commented:
“Armed with the downhole survey data we gathered from KSZDD002, we have a high degree of confidence in the configuration of the follow up Surface TDEM and DHEM surveys over the B1 Target Area. These have been designed to refine the geometries of the two targets we have modelled.
The 16,000 Siemens, slightly dipping modelled body is of most interest at this stage. As exciting as this target could be, we have to plan prudently to maximise our chances of intercepting it with the drill bit at the next attempt.
We will mobilise the team and surveying equipment to test as quickly as we can this target and the 2,500 Siemen vertically dipping modelled body.
Thanks to the drilling of KSZDD002, we now have two conductors as priority future exploration targets. I look forward to providing further updates once we have been through our process of verifying the results independently.”
Further information in respect of the Company and its business interests is provided on the Company’s website at www.kavangoresources.com and on Twitter at #KAV.
For further information please contact:
Kavango Resources plc
Ben Turney
First Equity (Joint Broker)
+44 207 374 2212
Jason Robertson
SI Capital Limited (Joint Broker)
+44 1483 413500
Nick Emerson
Kavango Competent Person Statement
The technical information contained in this announcement pertaining to geophysics have been read and approved by Mr. Jeremy S. Brett, M.Sc., P.Geo., Senior Geophysical Consultant, Jeremy S. Brett International Consulting Ltd. in Toronto, Canada. Mr. Brett is a member of the Professional Geoscientists of Ontario, the Prospectors and Developers Association of Canada, the Canadian Exploration Geophysical Society, and the Society of Economic Geologists. Mr. Brett has sufficient experience that is relevant to geophysics applied the styles of mineralization and types of deposits under consideration to act as a Qualified Person as defined under the Canadian National Instrument 43-101, Standards of Disclosure for Mineral Projects.
Note to Editors:
THE KALAHARI SUTURE ZONE
Kavango’s 100% subsidiary in Botswana, Kavango Minerals (Pty) Ltd, is the holder of 16 prospecting licences covering 8,831.1km2of ground, including 14 licences over a significant portion of the 450km long KSZ magnetic anomaly in the southwest of the country along which Kavango is exploring for Copper-Nickel-PGM rich sulphide ore bodies. This large area, which is entirely covered by Cretaceous and post-Cretaceous Kalahari Sediments, has not previously been explored using modern techniques.
The area covered by Kavango’s KSZ licences displays a geological setting with distinct similarities to that hosting World Class magmatic sulphide deposits such as those at Norilsk (Siberia) and Voisey’s Bay (Canada).
The Norilsk mining centre is about 2,800km northeast of Moscow and accounts for 90% of Russia’s nickel reserves, 55% of its copper and virtually all of its PGMs. Kavango’s licenses in the KSZ display a geological setting with distinct geological similarities to the magmatic sulphide deposits at Norilsk. Magma plumbing systems are a key feature of these deposits.
KSZ DEFINITIONS
Chalcopyrite: A copper rich sulphide mineral (CuFeS2), widely occurring in magmatic sulphide ore bodies.
EM Super Conductors: are bodies of highly conductive minerals such as graphite, magnetite and metal sulphides, which conduct electricity very rapidly provided the mineral grains are in contact with each other.
Gabbro/gabbroic: A coarse grained, medium to dark coloured rock, formed from the intrusion of mantle derived molten magma into the earth’s crust. Gabbroic rocks (or “gabbros”) are formed as the molten magma crystallizes and cools.
Gabbroic sills: Relatively thin, planar, horizontal bodies of solidified gabbroic magma that intruded into layers of sedimentary rock whilst still molten.
Karoo: The Karoo System covers 1.5 million km2 of the semi-desert region of Southern Africa. Rocks in this system formed 180-310 million years ago.
Massive sulphide: When a deposit consists almost entirely of sulphides it is termed “massive”. When it consists of grains or crystals of sulphide in a matrix of silicate minerals, it is termed “disseminated”.
Metal/Magmatic sulphide: Deposits of sulphide mineral concentrations in mafic and ultramafic rocks, derived from immiscible sulphide liquids. To view a video of how metal/magmatic sulphides form please visit –
https://twitter.com/KavangoRes/status/1316004057895645186?s=20
Norilsk Style: copper/nickel/PGE mineralisation associated with the intrusion into the upper parts of the Earth’s crust of mafic magma, which form magma chambers that sit below volcanic vents or fissures that extrude basaltic lava onto the surface (Hawaii is a possible modern equivalent). The Norilsk intrusions tend to have distinct morphologies, combining thin gabbro sills (wings) with deep keels (thought to be associated with feeder dykes) at the base.
Norilsk Model: a genetic geological model similar to that pertaining to the Norilsk/Talnakh deposits in Siberia. Traditionally, it was thought that, during emplacement, the magma incorporated sulphur rich country rock (e.g. coal measures) or evaporites into the melt, which allowed the molten magma to become sulphur saturated. The free sulphur would then combine, preferentially, with Cu/Ni/PGE metal ions to form metal sulphides, which, being heavy, tended to accumulate in traps or into the keel of the magma chamber. However, modern research suggests that the process might be more complex and may also involve changes of the chemical and physical properties of the magma during the introduction of new pulses of molten material from below. Such sudden changes may have caused rapid segregation of metal sulphides within and above the feeder dykes within the keel of the intrusion.
Pegmatitic: Pegmatites are very coarse grained igneous rocks having grain sizes in excess of 3cm, Pegmatites are thought to form as a result of very slow crystallisation and may contain exotic minerals from a volatile-rich melt.
Sulphide mineralisation: If there is sufficient sulphur in the molten magma, it will tend to combine with metals (Cu, Zn, Ni, Co, Pb, PGEs etc.) to form metal sulphide complexes, which may coalesce to form massive sulphide deposits. If the melt is sulphide poor, the metals will be taken up into the silicate minerals that form as the magma cools and will not usually form economic deposits.
Kavango Resources #KAV – KSZ Update & Expansion
Kavango Resources plc (LSE:KAV), the exploration company targeting the discovery of world-class mineral deposits in Botswana, is pleased to provide an update on its Kalahari Suture Zone (“KSZ”) Project.
Highlights:
Ø Update on Hole TA2DD002:
– TA2DD002 is the second hole in the planned 6-hole programme currently being undertaken to investigate the Karoo gabbros in the Hukuntsi section of the KSZ.
– Double shift drilling commenced on Friday 20 August
– As of 1800 on Sunday 22 August the Hole was at 137m
– Hole to test deeper Karoo gabbro “keel”, believed to be connected to the same gabbro encountered in Hole TA2DD001 (announced 16 August 2021), 1km to the west
– Additional objective to test potential contact between Karoo and Proterozoic gabbros, which might represent a possible ‘feeder zone’
– Hole to target western part of the same >1km geophysical anomaly (“Target A2”) drilled at Hole TA2DD001 (announced 20 April 2021)
– Anticipated target depth of 400m to 450m (though preparations in place to drill up to 800m depending on contact with any gabbro encountered)
Ø Downhole electromagnetic (“EM”) survey Hole TA2DD001
– Hole cased down to 393m from surface with steel casing, because of broken ground conditions
– EM probe run by Spectral Geophysics Ltd (“Spectral) from 394m to 560m
– According to analysis from Spectral, the A2 Time Domain Electromagnetic (“TDEM”) anomaly has been masked by the steel casing at 370m (i.e. the EM signal could not penetrate it)
– Results inconclusive, but alternative options being evaluated for future hole design and possible downhole EM surveys
Ø Award of two new PLs in the KSZ covering a combined 1,258km2
– Applied for in March 2021
– PL081/2021 covers 987.8km2 across the eastern edge of the KSZ
– PL080/2021 covers 270.4km2 and is contiguous with the Company’s existing PLs in the northern section of the KSZ
– Both are 3-year licences, with the option of two 2-year renewal periods
– £52,000 spending commitment in each PL over first 3 years
– Kavango now holds 14 PLs in the KSZ, covering 8,751.7km2
Ben Turney, Chief Executive Officer of Kavango Resources, commented:
“I’m very pleased at how quickly we’ve progressed to double shift drilling at Hole TA2DD002. We are now successfully moving through the gears of this drill campaign. The speed at which Equity Drilling/Mindea safely mobilised the rig to the new site is encouraging.
Core recovery continues to be consistent and of the highest standard.
Meanwhile, the inconclusive results of the downhole EM survey of Hole TA2DD001 emphasise some of the engineering challenges we face. Keeping a deep hole open to depth in the KSZ is tough. It’s a credit to the drillers that Spectral got the EM probe from 394m depth to 560m, but the steel casing from surface to 393m meant readings could not be taken below this depth. We now believe the primary A2 Conductor is at 370m.
While the cores we extract are by far the most important data source, it would have been helpful to see the EM response of the A2 Conductor at its base. The steel casing will be left in place for the time being, until the downhole survey (to confirm the orientation of the hole) is completed. At this point we will seek to remove the casing and possibly run another, shallower downhole EM survey. However, given what we have experienced so far with the ground closing in on itself, we have modest expectations about whether this will be possible.
Whatever the case, the results of the assays and the whole rock geochemical analyses should provide us with the most valuable evidence we need to guide future exploration.
With the award of 1,258km2 of new prospecting licences and working capital over £3million, Kavango is well-positioned to take full advantage of its strategic hold over this highly prospective region.”
Further information in respect of the Company and its business interests is provided on the Company’s website at www.kavangoresources.com and on Twitter at #KAV.
For further information please contact:
Kavango Resources plc
Ben Turney
First Equity (Joint Broker)
+44 207 374 2212
Jason Robertson
SI Capital Limited (Joint Broker)
+44 1483 413500
Nick Emerson
Kavango Competent Person Statement
The technical information contained in this announcement and the map of the A-C Corridor have been read and approved by Mr Mike Moles (BSc (Geology) & BSocSci (African Studies), who is a Member of the Australian Institute of Mining & Metallurgy (MAusIMM) and has sufficient experience that is relevant to the style of mineralisation and type of deposits under consideration to qualify as a Competent Person as defined in the 2012 Edition of the ‘Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves’. Mr Moles is a beneficial shareholder of Kavango Resources plc.
Note to Editors:
THE KALAHARI SUTURE ZONE
Kavango’s 100% subsidiary in Botswana, Kavango Minerals (Pty) Ltd, is the holder of 14 prospecting licences covering 8,751.7km2 of ground, including 12 licences over a significant portion of the 450km long KSZ magnetic anomaly in the southwest of the country along which Kavango is exploring for Copper-Nickel-PGM rich sulphide ore bodies. This large area, which is entirely covered by Cretaceous and post-Cretaceous Kalahari Sediments, has not previously been explored using modern techniques.
The area covered by Kavango’s KSZ licences displays a geological setting with distinct similarities to that hosting World Class magmatic sulphide deposits such as those at Norilsk (Siberia) and Voisey’s Bay (Canada).
The Norilsk mining centre is about 2,800km northeast of Moscow and accounts for 90% of Russia’s nickel reserves, 55% of its copper and virtually all of its PGMs. Kavango’s licenses in the KSZ display a geological setting with distinct geological similarities to the magmatic sulphide deposits at Norilsk. Magma plumbing systems are a key feature of these deposits.
KSZ DEFINITIONS
EM Super Conductors: are bodies of highly conductive minerals such as graphite, magnetite and metal sulphides, which conduct electricity very rapidly provided the mineral grains are in contact with each other.
Gabbro/gabbroic: A coarse grained, medium to dark coloured rock, formed from the intrusion of mantle derived molten magma into the earth’s crust. Gabbroic rocks (or “gabbros”) are formed as the molten magma crystallizes and cools.
Gabbroic sills: Relatively thin, planar, horizontal bodies of solidified gabbroic magma that intruded into layers of sedimentary rock whilst still molten.
Karoo: The Karoo System covers 1.5 million km2 of the semi-desert region of Southern Africa. Rocks in this system formed 180-310 million years ago.
Massive sulphide: When a deposit consists almost entirely of sulphides it is termed “massive”. When it consists of grains or crystals of sulphide in a matrix of silicate minerals, it is termed “disseminated”.
Metal/Magmatic sulphide: Deposits of sulphide mineral concentrations in mafic and ultramafic rocks, derived from immiscible sulphide liquids. To view a video of how metal/magmatic sulphides form please visit –
https://twitter.com/KavangoRes/status/1316004057895645186?s=20
Norilsk Style: copper/nickel/PGE mineralisation associated with the intrusion into the upper parts of the Earth’s crust of mafic magma, which form magma chambers that sit below volcanic vents or fissures that extrude basaltic lava onto the surface (Hawaii is a possible modern equivalent). The Norilsk intrusions tend to have distinct morphologies, combining thin gabbro sills (wings) with deep keels (thought to be associated with feeder dykes) at the base.
Norilsk Model: a genetic geological model similar to that pertaining to the Norilsk/Talnakh deposits in Siberia. Traditionally, it was thought that, during emplacement, the magma incorporated sulphur rich country rock (e.g. coal measures) or evaporites into the melt, which allowed the molten magma to become sulphur saturated. The free sulphur would then combine, preferentially, with Cu/Ni/PGE metal ions to form metal sulphides, which, being heavy, tended to accumulate in traps or into the keel of the magma chamber. However, modern research suggests that the process might be more complex and may also involve changes of the chemical and physical properties of the magma during the introduction of new pulses of molten material from below. Such sudden changes may have caused rapid segregation of metal sulphides within and above the feeder dykes within the keel of the intrusion.
Sulphide mineralisation: If there is sufficient sulphur in the molten magma, it will tend to combine with metals (Cu, Zn, Ni, Co, Pb, PGEs etc.) to form metal sulphide complexes, which may coalesce to form massive sulphide deposits. If the melt is sulphide poor, the metals will be taken up into the silicate minerals that form as the magma cools and will not usually form economic deposits.