Manitoba Group Stratigraphic range: Middle Devonian to Late Devonian |
|
---|---|
Type | Geological formation |
Sub-units |
Souris River Formation Hubbard Evaporite Dawson Bay Formation |
Underlies | Duperow Formation 9Saskatchewan Group |
Overlies | Prairie Evaporite Formation, Winnipegosis Formation (Elk Point Group) |
Thickness | up to 244 metres (800 ft) |
Lithology | |
Primary | Shale, carbonate, evaporite |
Location | |
Region | WCSB |
Country | Canada |
Type section | |
Named for | Manitoba |
Named by | A.D. Baillie, 1953 |
The Manitoba Group is a stratigraphical unit of middle to late Devonian age in the Western Canadian Sedimentary Basin.
It takes the name from the province of Manitoba, and was first defined by A.D. Baillie in 1953.
The Manitoba Group is composed of alternating cycles of shale, carbonate and evaporite.
The Manitoba Group occurs in outcrop in southwestern Manitoba and in the sub-surface in southern Saskatchewan, North Dakota and Montana. It reaches a maximum thickness of 150 metres (490 ft) in outcrop and up to 244 metres (800 ft) in the sub-surface.
The following formationas are recognised, from top to bottom:
The Manitoba Group is conformably overlain by the Duperow Formation and disconformably overlays the Prairie Evaporite Formation or Winnipegosis Formation of the Elk Point Group.
The lower Manitoba Group is equivalent to the Muskeg Formation in northern Alberta, while the upper part correlates with the Beaverhill Lake Formation.