The AB zone is underlain by pillowed and massive submarine basalts of the Vancouver Group, Upper Triassic Karmutsen Formation, which has undergone low grade greenschist regional metamorphism. Subaerial amygdaloidal basalt flows lie to the south of the area. The basalts are cut by numerous north trending basalt and feldspar porphyry dikes.

A large quartz breccia and stockwork of veins, up to 10 metres wide, strike northerly continuously for 600 metres and intermittently for 1400 metres. The quartz veins are localized by dominant north-northeast faults and subordinant north-northwest faults. These faults and quartz veins are offset by a younger set of northeast to east trending faults.

Basalts adjacent to both orientations of faults are often chloritized and carbonatized as is the wallrock adjacent the quartz veins.

Gold is associated exclusively with the quartz veins. Pyrite and minor arsenopyrite occur as disseminations and vein and fracture fillings.

Gold values are generally isolated and only locally continuous. A quartz breccia and stockwork zone assayed 10.8 grams per tonne gold over 1 metre, a sample 400 metres to the northeast assayed 17.7 grams per tonne gold over 1 metre, and a sample 300 metres to the northwest assayed 15.2 grams per tonne gold (Assessment Report 11084).