100Ktpa not 50Ktpa, and it's definitely not seam-like IMO. They've said there's no visible structural controls - it's broad, kilometre-scale hydrothermal alteration.
Keep in mind that these are still partial extractions but it will be random diffuse zones of super high grades mixed with normal high grades (no evidence of any low grade or barren zones yet
) which will have sub-tabular or elliptical geometry.
There could be some variable subparallel or oblique trends and some strike\dip variation in the trends. A bit like if you soaked a firm foam pillow in water then squeezed it. Some parts of the pillow will get some of the water squeezed out and some parts will remain saturated. High grade trends (not reefs) could look something like this interp from Ema :