The Tenas occurrence is located on Tenas Creek, approximately 2 kilometres south of its creek mouth on the Nitinat River.

The area is underlain by extensively faulted rocks of the Upper Triassic Vancouver Group and the Lower Jurassic Bonanza Group. The basal Vancouver Group sequence is comprised of basalt flows, breccias and tuffs of the Karmutsen Formation overlain by Quatsino Formation limestone, which is in turn overlain by black argillites of the Parsons Bay Formation. The overlying Bonanza Group consists of a sequence of argillites, cherts, cherty tuffs, volcanic and/or sedimentary breccias, sandstones and basaltic to rhyolitic flows. The entire package of rocks has been broadly to tightly folded, with axes generally trending northwest.

Locally, a sulphide-rich band or zone, possibly skarn, hosts pyrite and chalcopyrite. A grab sample (GL-78-R5) assayed 0.57 gram per tonne gold, while a float sample (GL-77-R-56) assayed 1.29 per cent copper and 9.5 grams per tonne silver (Property File - G.W. Laforme (1978-11-01) - Report - Proposal to Investigate the Lower Reaches of Granite Creek and Tenas Creek - Cowichan Lake Project).

In 1964, Avallin Mines completed a program of soil sampling and geological mapping on the area as the O.G.M. claims. In 1969, Quintana Minerals completed a program of regional soil sampling and geological mapping. In 1987, Nuspar Resources completed a program of geological mapping minor drilling on the area as the Wabana 1-2 claims.