The area is underlain by three Lower to Middle Jurassic formations; Betty Creek, Mount Dillworth and Salmon River, that form a moderately east dipping conformable sequence. Upper Betty Creek Formation consists of heterogeneous grey, green and, locally, red dacitic tuffs or flows with thin interbeds of green and reddish conglomerate and wacke. Mount Dillworth Formation consists of white weathering dacitic to rhyodacitic lapilli tuff and ash tuff. Lower Salmon River Formation is black, turbiditic siltstone and shale with thin horizons containing calcareous concretions.

Mineralization occurs within a 200 by 500 metre area of iron carbonate alteration within Betty Creek Formation. Thin pyrite- quartz-carbonate chlorite veinlets occur that locally carry trace amounts of chalcopyrite. Veins and alteration appear to be con- trolled by fractures in the host rocks. One sample of these veins contained 38.1 grams per tonne silver and 0.21 per cent copper (Assessment Report 14659).