Fig. 1. Map of the Athabasca region in the northern parts of Alberta and Saskatchewan, Canada, showing a portion of the Precambrian Athabasca sandstone (gray, concentric circle-pattern), the Carswell crater (astrobleme), the area of the Alberta bituminous (tar) sands in the Cretaceous Mannville Formation, and the location of the AOC Granite 7-32-89-10 drill hole northwest of Fort McMurray. Major faults and fracture systems (dashed lines) that extend through the tar sands are also shown. Map provided by C. Warren Hunt of the Anhydride Oil Corporation.