 Clark earned Bachelor's and master's degrees from McMaster University before obtaining a Doctorate in Chemistry from the University of Illinois.He began work at the Geological Survey of Canada in 1915, where he became interested in oil sands.In 1920 he moved to Edmonton and joined the University of Alberta and a forerunner of the Alberta Research Council, where be began experimenting with separating bitumen from the Athabasca oil sands, a large oil sand deposit in northeastern Alberta.