Belly River Group

Belly River Formation Stratigraphic range: Santonian to Campanian PreЄ Є O S D C P T J K Pg N
Belly River beds exposed along the Oldman River
Type	Geological formation
Underlies	Bearpaw Formation
Overlies	Wapiabi Formation
Thickness	up to 1,300 metres (4,270 ft)
Lithology
Primary	Sandstone, Shale
Other	Conglomerate, Coal, Bentonite
Location
Coordinates
Region	Alberta
Country	Canada
Type section
Named for	Belly River
Named by	George Mercer Dawson, 1883

The Belly River Formation is a stratigraphical unit of Late Cretaceous age in the Western Canadian Sedimentary Basin.

It takes the name from the Belly River, a tributary of the Oldman River in southern Alberta, and was first described in outcrop on the banks of the Oldman River (at the time considered part of the Belly River) and Bow River by George Mercer Dawson in 1883.

Lithology

The Belly River Formation is composed of very fine grained sandstone with coarse grained beds and minor bentonite, coal, green shale and concretionary beds.

Hydrocarbon production

Gas is produced from the Belly River Formation in the Deep Basin, in west-central Alberta and in the Canadian Rockies foothills.

Paleofauna

Dinosaur remains are among the fossils that have been recovered from the formation.

Dinosaurs reported from the Belly River Group
Genus	Species	Location	Stratigraphic position	Material	Description	Images
Montanoceratops	Indeterminate					Montanoceratops

Distribution

The Belly River Formation reaches a maximum thickness of 1,300 metres (4,270 ft) in its western reaches, and thins out eastward to about 350 metres (1,150 ft) in the Canadian Plains. It is found throughout southern Alberta, and as far east as eastern Saskatchewan. From south to north, it is present from the United States border to the Wapiti River region, south of the Peace River Country.

Relationship to other units

The Belly River Formation is conformably overlain by the Bearpaw Formation and gradually overlies the Wapiabi Formation, the Colorado Group shale or the Lea Park Formation shale.

It is equivalent to the Milk River Formation and Pakowki Formation. The Belly River has group status in the Canadian Rockies foothills and is replaced by the Oldman Formation (Judith River Formation in Montana) and Foremost Formation in southern Alberta.

See also

• List of dinosaur-bearing rock formations