Whitehorse Trough is a frontier basin in south-central Yukon that is thought to contain gas and possibly oil. Over 400 samples from the Whitehorse Trough have been analysed by programmed pyrolysis and combustion, which together with coal rank, vitrinite reflectance, and the colour of microfossils indicate the following: the Povoas formation has no source rock potential; the Aksala formation is a poor source rock, probably gas-prone and postmature; the Richthofen formation is a poor to fair source rock, gas-prone and postmature; the Nordenskiold formation has no source rock potential; and the Tanglefoot and Tantalus formations are potentially good to very good source rocks, mainly gas-prone with a possibility of oil and mature. The Aksala and Richthofen formations are interpreted as spent source rocks, whereas the Tanglefoot and Tantalus formations are interpreted as potential source rocks and possibly effective source rocks. The most prospective
areas for hydrocarbon exploration are Division Mountain, Tantalus Butte and Five Finger Rapids.