Great big long deep cracks (strike length) in the Earth get filled up with liquid super heated quartz, cools off and solidifies to create the ore body. Drilling is done starting few hundred meters outside the zone at 45-50 degree angles, depending on what depth you want to intercept the across strike for the zone. Inorder to determine the tonnage of each zone the widths of the zones have to be determined. These long strike lengths, still to be determined as they are still open probably go relatively straight down from surface in a zig-zag manner, and historically have shown to go beyond 1000m in similar type deposits. This is where the "Belt Theory" comes from, as the lengths of the large openings which could be between 5 to 50 meters wide go on for still to be determined distances.

Skier