The area is underlain by Lower Jurassic Bonanza Group volcanics and sediments, intruded by granodiorite of the Jurassic Island Plutonic Suite.

Locally, pyrite, chalcopyrite and magnetite occur as disseminations and fracture coatings in sheared and intensely fractured andesite. The fracture/shears trend 045 degrees, dipping vertically. Cryptocrystalline quartz stringers are present. A granodiorite stock is located 2.2 kilometres to the east.

The occurrence is located near to the Island Copper deposit (refer to 092L 158-Island Copper for details).