The Iosegun Lake area is only thinly covered by drift in the more rugged, hilly areas. The drift thickness may exceed 200 feet (60 m) in the area of Little Smoky River where thick buried valley sand forms an important aquifer from which yields in excess of 25 igpm (2 l/sec) are common. A continental sandstone-shale sequence, the Paskapoo Formation of Paleocene-Late Cretaceous age, underlies most of the southern and southwestern parts of the area and contains sandstone aquifers generally capable of producing upwards of 25 igpm (2 l/sec) to a single well. The Wapiti Formation, a continental sequence of bentonitic and clayey sandstones of Late Cretaceous age, underlies the remainder of the area. Aquifers within this formation are generally thin and discontinuous. Yields in a single well usually range between 5 to 25 igpm (0.4 to 2 l/sec).
Sodium bicarbonate waters with total dissolved solids contents between 500 and 1500 ppm are the rule in the normally utilized aquifers, although wells completed in the Paskapoo Formation tend to have somewhat higher percentages of calcium and magnesium, and lower total dissolved solids contents.
Tokarsky, O. (1977): Hydrogeology of the Iosegun Lake area, Alberta; Alberta Research Council, ARC/AGS Earth Sciences Report 1976-02, 13 p.