Middle Island Resources Limited announced that the drilling program on the 100% owned East Tennant region at Barkly in the Northern Territory has begun and that the first drill hole has been completed. The primary objective was to test the Crosswinds target for the potential of hidden IOCG and/or SEDEX style mineralization to host a large-scale Copper-Gold deposit. This drilling was located based on geophysics from aeromagnetic and the Induced Polarization (IP) conducted earlier in the year.

Drilling of the first hole at the Crosswinds prospect has been completed to 808.4m. The Crosswinds prospect was a discovery based on an initial expression of Malachite mineralization observed at surface as mentioned in ASX release 23 December 2020. The early geological interpretations of the Crosswinds prospect suggested there was a proximal source of mineralization beneath the overlying Georgina Basin with malachite at the surface.

This secondary mineralization has migrated along growth fault structures bringing the oxide copper mineralization to surface. The drilling was very straight and kept to the target area. Some issues were incurred when transitioning from the base of the Georgina Basin (and basal Helen Springs Volcanics) to the Alroy Formation but this did not affect the drill direction and continued to the target area.

Within the upper Alroy Formation, a sequence of thick hematite alteration zones was observed. This upper zone also showed fine micaceous (biotite) schist. Throughout the Alroy sequence small quartz veins were observed being in some cases brecciated and hematite altered.

The first drill hole passes through hematite at 200m and again at 220m down hole. This is below the contact with the Georgina sediments into the Alroy Formation. IOCG deposits generally follow growth faults from fluid accumulation as deep as 5km.

Along these growth faults, from closest to surface, can expect to see hematite, magnetite, disseminated sulphides to massive sulphides carrying economic metal content. It was expected that following the hematite would see a sequence of disseminated sulphides then massive sulphides. The absence of the sulphides may be due to intersecting the edge of the deposition.

It is for this reason that MDI plans a second hole in the Crosswinds target drilling at in the opposite direction from the first hole aiming to intersect the potential middle of the sulphide zone.