The Douglas Channel map area lies within the Coast belt and contains 77 recorded mineral occurrences. The belt consists intermediate granitic rocks of the Coast Plutonic Complex, migmatite and metamorphic rocks of the central gneiss complex in the northeast part of the map, and discontinuous synformal zones of metasedimentary and metavolcanic schist between plutons or within the central gneiss complex.
The types of occurrences in the area consist of gold-bearing pyritized quartz veins; sulphide replacements of skarn or schist with copper and gold; limestone, marble and dimension stone; garnet and kyanite; silica; mica; and thermal springs. The Surf Inlet and Pugsley mines (103H 027), which produced 12 million grams of gold between 1902 and 1943, are currently being evaluated underground rehabilitation and drilling. Here, several shear zones contain auriferous quartz veins within dioritic gneiss. The Ecstall deposit (103H011) and a cluster of thirteen other showings, including the Packsack prospect (103H 013), occur within the Scotia-Quaal metamorphic belt, a ?Proterozoic-Paleozoic metasedimentary and metavolcanic sequence that includes the Middle Devonian Big Falls orthogneiss, Early Jurassic orthogneiss, and Jurassic or Cretaceous mafic and utramafic rocks. The showings occur in hydrothermally altered volcanic-volcaniclastic rocks, close to a felsic volcanic centre. At the Ecstall deposit, two massive pyrite lenses contain 6,349,700 tonnes of 0.6 per cent copper, 2.5 per cent zinc, 42.3 per cent iron, 48.4 per cent sulphur, 20.0 grams per tonne silver and 0.5 gram per tonne gold.