Placer gold deposits of the Quesnel Highland region, including the former rich producers of the Barkerville camp, have accounted for a large proportion of British Columbia's alluvial gold production. With the exception of a few producers in the Wingdam area, which are underlain by Upper Triassic sediments correlative with the Nicola Group, almost all the deposits are underlain by the Upper Proterozoic to Lower Paleozoic Snowshoe Group. These rocks have been metamorph- osed to greenschist facies and are predominantly metasedimentary.
Placer gold deposits in the region are generally found in relatively young Pleistocene gravels. The morphology and mineral associations of the gold suggests that it was derived locally, the most obvious sources are the numerous auriferous veins in the Downey succession of the Snowshoe Group.
In the upper part of Shepherd Creek there is a series of old stream channels that have been partly cut away by more recent streams and have been modified by glacial erosion and deposition. Included in the old stream channels is at least one that is a cross channel to the present Shepherd Creek. The old channels are filled with gravels that are mainly glacial. Gold is unevenly distributed within the gravels and is most abundant on bedrock. Little gold occurs in the lower part of Shepherd Creek where the creek flows in a narrow, deep valley.
"Data from the Cariboo mining district indicate that supergene leaching of gold dispersed within massive sulphides by Tertiary deep weathering followed by Cenozoic erosion is the most likely explanation for the occurrence of coarse gold nuggets in Quaternary sediments" (Exploration in British Columbia 1989, page 147).