Only got time to read this today.
Taking the maps and sections as presented....
- this is the first VMS with bornite in the stockwork zone. Bornite is formed by Cu rich, S poor fluids. You need a lot of sulphur to form a massive sulphide deposit, and this system would appear to be rather lacking in the sulphide department. This could explain why the only massive sulphide is a 20cm smear.
- the grade of this smear will be <30%, guaranteed. Remember it's "up to 30%'.
- but remember, also, TLM had a smear of high-grade sulphide and its Monty deposit was found down dip of the smear.
- this area of the Bryah is affected by large west-over-east thrust sheets formed by the Yarlarweelor Gneiss / Despair Granite being punched sideways into the bryah. The cross section seems to show this, as the shear with 'secondar mineralisation' is probably a thrust.
- if you take the pillow basalt facies as correct, then this is not an idea besshi setting as the Naracoota here is a flow and not a sill. The belt is still very prospective in this area, though, but a lack of sediments to be brewed up in this flow unit is probably an issue
- the footwall zone in the sediments could have been clipped off by the thrust and moved up and east, now eroded.
- alternately, the place to go may be down into the Ravelstone further west.
- take this plunge with a serious grain of salt. That long section which shows the red outline of the plunge is based on wishes, unicorn dreams, and conflating the DHEM plate in the south with the near-surface mineralisation...on the other side of a cross structure. Still worth jabbing the southern plate.
- the section which shows the massive sulphide blebs blowing out up-dip into a giant massive funnel shape of "massive sulphide"....well, that's a little disingenuous. Do these guys not know that copper gets dispersed in the regolith? Looks like simple dispersion to me.
- the DHEM may fail in a bornite / chalcocite dominant deposit due to lack of sulphide to create a conductor. in a sulphur poor system the blebs of sulphides may not connect up to form a conductor and present a weak or no response. IP, especially 3D IP, would be a good tool to use.
Still expecting a good 50m @ 0.25-0.5% Cu in this stringer zone if it's bornite.
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