The presence of the intrusive bodies suggests potential mineralisation and the company will seek to reinterpret the area for further mineralisation as information from the hole is received.
Unexpected change in geology
At a depth of 595 metres, the drill hole was within the Hardey Formation, a series of interbedded sediments and tuffs.
The lithology of the rock changed at a depth of 644.4 metres with an intermediate-felsic intrusive being intersected.
This change from the Hardey Formation at such a shallow depth was unexpected, with alteration, bleaching and several quartz veins being observed.
At a depth of 901.6 metres the geology changed again to narrow dolerite dykes intersecting the intermediate-felsic intrusive.
The super-deep hole is designed to test the many rock sequences in the Pilbara Basin from surface.
These rock sequences are not known or are interpreted or inferred to exist based on sparse data that does not explain observed surface mineralisation for diamonds, cobalt, zinc, lead and gold.
Drill core from the hole is being logged and photographed at Artemis’ Radio Hill Operations 40 kilometres to the north.
It will then be sent to the Geological Survey of Western Australia’s Perth Core Library for analysis.