The Joli Fou Formation is a allostratigraphical[2] unit of middle Albian age in the Western Canadian Sedimentary Basin.

[3] The Joli Fou Formation is composed of shale with minor sandstone lenses.

The shale is non-calcareous, dark grey, while the sandstone lenses are fine to minor medium grained, quartzose or micaceous.

It occurs throughout the Western Canadian Sedimentary Basin, from the Rocky Mountain Foothills to south-central Saskatchewan.

In south-eastern Alberta, the base of the Formation contains the Cessford Sand marker, consisting of sandstone, siltstone and mudstone.