Muskwa Formation
Stratigraphic range: Frasnian PreꞒ Ꞓ O S D C P T J K Pg N
Type	Geological formation
Unit of	Horn River Formation
Underlies	Fort Simpson Formation
Overlies	Otter Park Member
Thickness	up to 34 metres (110 ft) [1]
Lithology
Primary	Shale
Location
Coordinates	58°44′38″N 122°40′41″W / 58.7438°N 122.6781°W / 58.7438; -122.6781 (Western National Gas Fort Nelson a-95-J/94-J-10)
Region	British Columbia
Country	Canada
Type section
Named for	Muskwa River
Named by	Gray & Kassube
Year defined	1963
Muskwa Formation (Canada)

The Muskwa Formation is a stratigraphical unit of Frasnian age in the Western Canadian Sedimentary Basin.

It takes the name from Muskwa River, and was first described in the Western National Gas Fort Nelson a-95-J/94-J-10 well by F.F. Gray and J.R. Kassube, in 1963.

Lithology

The Muskwa Formation is composed of bituminous shale. Pyrite is a common accessory mineral.

Gas production

Gas is produced from the Muskwa Formation shales in the Horn River Basin in the Greater Sierra oil field in north-eastern British Columbia. Horizontal drilling and fracturing techniques are used to extract the gas from the low permeability shales (see Shale gas).

Distribution

The Muskwa Formation occurs in northern Alberta, north-eastern British Columbia and in the southern part of the Northwest Territories, and typically has a thickness of 34 metres (110 ft).

Relationship to other units

The Muskwa Formation is a sub-unit of the Horn River Formation; it is conformably overlain by the Fort Simpson Formation and conformably underlain by the Otter Park Member.

See also

• Muskwa Ranges

References