| Muskwa Formation | |
| Type: | Geological formation |
| Period: | Frasnian |
| Prilithology: | Shale |
| Namedfor: | Muskwa River |
| Namedby: | Gray & Kassube |
| Year Ts: | 1963 |
| Region: | British Columbia |
| Country: |  Canada |
| Coordinates: | 58.7438°N -122.6781°W |
| Unitof: | Horn River Formation |
| Underlies: | Fort Simpson Formation |
| Overlies: | Otter Park Member |
| Thickness: | up to 34m (112feet)[1] |
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.
The Muskwa Formation is composed of bituminous shale. Pyrite is a common accessory mineral.
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).
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 34m (112feet).
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.