Basic for a good gold geo, but they're few and far between. Where it gets interesting is the relationship between the angle of intersection of the controlling structures\lithology and the strike length\thickness\morphology of the HG shoots --> $$$. I haven't studied it but I imagine that an angle of more than 60 degrees is bad (?PDI) but there'd be a sweet spot at around 30 degrees which will open up the ground just right.
