||This article provides insufficient context for those unfamiliar with the subject. (August 2012)|
Stratigraphic range: Late Cretaceous
Horseshoe Canyon Formation of the Edmonton Group
|Sub-units||Battle Formation, Whitemud Member, Horseshoe Canyon Formation|
|Overlies||Bearpaw Formation, Belly River Group|
|Thickness||328 metres (1,080 ft) to 763 metres (2,500 ft)|
|Named by||Joseph Tyrrell, 1887|
The Edmonton Group is composed fine grained calcareous sandstone and sandy shale with bentonite, ironstone concretions and coal. The sediments were deposited in fresh and brackish water environments. 
The Edmonton Group reaches a maximum thickness of 763 metres (2,500 ft) in the Canadian Rockies foothills, and is typically 350 metres (1,150 ft) thick in the plains. It forms the erosional surface in Central Alberta and often forms badlands topography.
Relationship to other units
It is equivalent to Fox Hills Formation in Saskatchewan and is not differentiated in the upper Montana Group. It can be correlated with the Horsethief Formation in Montana, the Lennup Formation and Muteetse Formation in Wyoming, the Blood Reserve Formation and St. Mary River Formation in southern Alberta, with the Eastend Formation, Whitemud Formation, Battle Formation and Frenchman Formation in the Cypress Hills, with the Fox Hills Formation and Lace Formation in Montana, as well as with the Wapiti Group and Brazeau Group in the Canadian Rockies foothills.
Subdivisions of the Edmonton Group include:
|Battle Formation||Maastrichtian||bentonitic silty shale, montmorillonitic clay||14 m (50 ft)|||
|Whitemud Member||Maastrichtian||bentonitic shale, argillaceous sandstone||6 m (20 ft)|||
|Horseshoe Canyon Formation||Maastrichtian||sandstone, siltstone, shale||227 m (740 ft)|||
- Lexicon of Canadian Geologic Units. "Edmonton Group". Retrieved 2009-03-01.
- Tyrrell, J.B., 1887. Report on a part of northern Alberta and portions of adjacent Districts of Assiniboia and Saskatchewan. Geological Survey of Canada, Ann. Rept.1886, new ser., v.11, Part E, p.1-176.
- Lexicon of Canadian Geologic Units. "Battle Formation". Retrieved 2010-01-03.
- Lexicon of Canadian Geologic Units. "Whitemud Member". Retrieved 2010-01-03.
- Lexicon of Canadian Geologic Units. "Horseshoe Canyon Formation". Retrieved 2010-01-03.