Middle Island moves to expand NT copper-gold tenure

ASX-listed gold and base metals explorer, Middle Island Resources is looking to pick up more ground at its exciting Barkly copper-gold project in the Northern Territory’s East Tennant region. The Perth-based company has made an application for a further 809 square kilometres of prized territory that will swell its project tenure to 5,220 square kilometres across 13 exploration licences.

Middle Island’s new exploration licence application area sits along strike from its recent Crosswinds copper discovery, which in turn lies about 50km south-west of an encouraging, recently completed copper-mineralised MinEx CRC drill hole – NDIBK04.

Under Australia’s National Drilling Initiative, 10 deep stratigraphic diamond holes totalling about 4,000m that were recently drilled by MinEx CRC intersected prospective basement rocks between 80m and 200m depth, the company says.

Pre-collared diamond hole NDIBK04 intersected localised semi-massive copper mineralisation along with more than 300m of disseminated-to-blebby sulphides to the end of hole.

Middle Island says NDIBK04 encountered widespread disseminated-to-blebby sulphides below 89.5m depth to the end of hole at 416.3m including pyrite, pyrrhotite, marcasite, chalcopyrite – a copper sulphide – and arsenopyrite, possible pointers to mineralisation.

Most of the NDI holes pierced strong haematite-magnetite alteration within Proterozoic basement rocks beneath the Georgina Basin.

Preliminary results from the MinEx CRC drilling program vindicate Middle Island’s first mover status in the fertile Barkly setting, the company says.

The NT Government also announced at a conference last month that it has significantly increased government co-funding for geophysics and drilling programs from $1 million a year to $9.5 million a year.

Middle Island has submitted applications to the government for exploration collaboration co-funding to help carry out detailed airborne magnetic and ground gravity surveys in the Barkly area that, along with possible airborne electromagnetic surveys, are planned to be completed during the 2021 dry season.

Data from the survey work will go towards the company’s refining and prioritising of basement iron-oxide copper-gold targets at Barkly in advance of drilling it has earmarked to take place next year.

The most persistent and visually evident aspect of the NDI East Tennant drill core is the widespread development of haematite and magnetite alteration within Proterozoic sediments and felsic intrusives in almost all holes.

Middle Island says this style of alteration is a key indicator of iron oxide copper gold-style mineralisation and is consistent with the gravity and magnetic signatures on which its drill target selection will be based.

Late last year it discovered “significant” copper oxide mineralisation at surface at Barkly’s Crosswinds prospect during reconnaissance exploration work.

The company reported spot portable XRF-gun readings of between 24.8 per cent and 76.2 per cent copper for Crosswinds and composite chip samples over an interval of 130m assaying an average 0.76 per cent copper.

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