The area around the junction of Sulphurets (formerly Sulphide) Creek and the Unuk River is underlain by Lower Jurassic Hazelton Group volcanics and volcaniclastics of the Unuk River Formation. The rocks are comprised of altered tuffs and lithic tuffs with minor chert, andesite and chloritic schists.

In 1929, free gold was reported in river gravels at the junction of Sulphurets (Sulphide) Creek and Unuk River. The gold is described as flaky and considerably worn and fine colours were seen in every pan of material tested. Local irregularities were noted in the bedrock near the placer gravels.

In 1935, a composite sample, taken from sand bars at the mouth of Sulphurets Creek, which contained abundant alluvial pyrite assayed 1.03 grams per tonne gold, trace silver, trace copper (Annual Report 1935, page B10).