Blairmore Group

Blairmore Group Stratigraphic range: Early Cretaceous
Type	Group
Sub-units	Cadomin Formation, Gladstone Formation, Beaver Mines Formation, Ma Butte Formation
Underlies	Crowsnest Formation, Alberta Group
Overlies	Kootenay Group
Thickness	up to 2,000 m (6,560 ft)
Lithology
Primary	Sandstone, siltstone, mudstone
Other	Conglomerate, limestone
Location
Region	Alberta  British Columbia
Country	Canada
Type section
Named for	Blairmore, Alberta
Named by	W.W. Leach, 1914

The Blairmore Group, originally named the Blairmore Formation, is a geologic unit of Early Cretaceous age in the Western Canada Sedimentary Basin that is present in southwestern Alberta and southeastern British Columbia. It is subdivided into a series of formations, most of which contain plant fossils. In some areas it contains significant reservoirs of natural gas.

The Blairmore group includes the conglomerate and quartzose sandstones of the Cadomin Formation at the base, and grades to sandstone, siltstone, mudstone, and limestone in the overlying formations. The Beaver Mines and Ma Butte Formations in the upper part of the group also include minor beds of bentonite and tuff.

The Blairmore Group is subdivided into the following formations from top to base:

Some early workers included the Crowsnest Formation, which overlies the Ma Butte Formation, at the top of the Blairmore Group, but that practice has been abandoned.

The name Blairmore Group is applicable in the foothills and mountains of southwestern Alberta and southeastern British Columbia, from the Canada–United States border northward to the Clearwater River. The equivalent strata north of the Clearwater River, which were originally assigned to the Blairmore Group, differ in that they contain major coal deposits and they have therefore been reassigned to the Luscar Group.

...
Wikipedia