In this area the geology from northeast to southwest, consists of northwest trending Karmutsen Formation andesites with minor limestone and Quatsino Formation limestone, both of the Upper Triassic Vancouver Group. The Vancouver Group rocks are overlain by Lower Jurassic Bonanza Group shales. To the south a thin shaly succession is in fault contact with the Karmutsen Formation.

In the northeast block of the Karmutsen Formation, disseminated chalcopyrite and pyrite are present in andesite close to interbedded limestone (Assessment Report 1719).