lets hope this is true, page-26

Unbeliever,

I hope you don't mind me commenting, but I think you should consider a few extra things about the Andewa geology.

Its probably more complex than what you have described. The depth of erosion since major volcanism is probably in the order of 2-3km. That puts us in magma chambers, as well as the extrusive rocks. Cu porphrys develope from magma chambers (intrusives) rather than extrusives. The mineralisation can however flow through from the intrusives into extrusives and other rock types.

Your point that ALL MINERALISATION is deep crust in origin is wrong. Some elements may be, heat and pressure may be but not mineralisation, for example epithermal mineralisation happens quite close to the surface. Porphyry copper gold mineralisation most commonly forms in the top 5kms. Thats why there are hardly any copper porphrys in rocks older than 100m years, most much younger. The older ones have long been eroded out.