The central Yukon Territory has a number of favourable placer deposit settings due to its unique history of multiple glaciations, active stream sedimentation in association with proglacial outwash settings and terrain which has remained unglaciated.
Placer gold was found along the Stewart River on point bars in 1884 prior to the discovery of gold in the Klondike area. This was the first indication that the Yukon Territory contained important economic concentrations of placer gold.
This study is concerned with the late Tertiary and Quaternary geology in the Lower Stewart River and adjacent Yukon River above Dawson. Previous systematic surficial geological mapping and testing for placer gold on the high-level terraces along these rivers has been limited. This report describes the sedimentology and stratigraphy of key gravelly exposures in this area because similar high-level terraces in the Fortymile River drainage in Alaska had been mined for gold for many years. Work of this type also provides information on the physical characteristics of gravelly deposits (e.g., grain size distribution) which may assist regulatory decisions on placer mining in the lower Stewart and Yukon drainages.
Accompanying this report are two 1:50 000-scale surficial geology maps including marginal notes (Garner Creek, NTS 115O/13 and Matson Creek and Ogilvie NTS 115N/9 (east half) and 115O/12), as well as one 1:250 000-scale topographic map (Stewart River - NTS 115N/O) including field study site locations, heavy mineral sample sites and hardrock mineral occurrences.
