This from the Bendigo Mining website.
Gold mineralisation is dated from the Upper Ordovician and is related to the compressional tectonism generating the chevron folds. Fold plunge reversals, differential attenuation of hinge zones giving rise to domes and sub-domes, and disruption and dilation caused by both bedding parallel and oblique reverse faulting, all play their part in localising gold mineralisation.
A reminder that there are always things we don’t know. I haven’t a clue what all this is about. And that’s kind of nice.