Keg River Formation

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Keg River Formation
Stratigraphic range: Givetian
TypeGeological formation
UnderliesMuskeg Formation
OverliesChinchaga Formation
Thicknessup to 300 metres (980 ft)[1]
Primarydolomite, limestone
Coordinates59°10′21″N 118°44′54″W / 59.1725°N 118.7482°W / 59.1725; -118.7482 (Keg River Formation)Coordinates: 59°10′21″N 118°44′54″W / 59.1725°N 118.7482°W / 59.1725; -118.7482 (Keg River Formation)
Region Alberta
Country Canada
Type section
Named forKeg River
Named byJ. Law, 1955

The Keg River Formation is a stratigraphic unit of Givetian age in the Western Canada Sedimentary Basin.

It takes the name from the Keg River, a tributary of the Peace River, and was first described in the California Standard Steen River 2-22-117-5W6M well (situated north of Zama Lake) by J. Law in 1955.


The Keg River Formation is composed of dark dolomite with intercrystalline or vuggy porosity and wackestone limestone. [1] The Rainbow Member and upper Keg River Member are reef formations deposited in the Rainbow, Zama and Bitscho sub-basins.

Hydrocarbon production[edit]

Oil is produced from the Keg River reefs in the Zama Lake and Rainbow Lake areas of north-western Alberta.


The Keg River Formation occurs in the subsurface from northeastern to northwestern Alberta and its southern border is defined by the Peace River Arch. It varies in depth from 10 metres (30 ft) to 300 metres (980 ft).[1]

Relationship to other units[edit]

The Keg River Formation is conformably overlain by the Muskeg Formation and unconformably overlays the Chinchaga Formation.[1]

It is equivalent to the Pine Point Formation, Hume Formation and Nahanni Formation in north-eastern British Columbia and the Northwest Territories and to the Winnipegosis Formation in Saskatchewan and eastern Alberta.


  1. ^ a b c d Lexicon of Canadian Geologic Units. "Keg River Formation". Archived from the original on 2009-04-16. Retrieved 2009-03-01.