As modern mineral exploration is increasingly looking for targets at greater depths and under cover there has been a paradigm shift to a conceptual targeting idea, that focuses on understanding the geological processes that control the distribution in Earth systems (the 'Haystack') and predict where and how these processes might combine to form an ore deposit (the 'Needle').
For the technically minded, the following 11 December 2019 article from Ben Kay, Kate Robertson, Stephan Thiel & Graham Heinson might be of interest:
It should be noted that the Kalkaroo deposit is located on second or third order synthetic faults associated with hanging wall anticlines above a bounding south east-dipping fault at depth (refer Figures 4 & 5 in the above article). The fault beneath the anticline could have been the conduit for fluids moving from the deep crust to upper crustal levels where they could have migrated into favourable depositional sites associated with second or third order structures.
I have recently suggested to Dr Giles that Havilah undertake a shallow MT survey over the fault/ vein zone at the Kalkaroo deposit to look for the 'Haystack'.
Cheers
These are only my thoughts and it does not constitute investment advice. Before acting on any information you read and before making any financial or investment decisions, you should always consult your advisor(s) or other relevant professional experts.
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