Liard Formation

Liard Formation
Stratigraphic range: Middle Triassic to Late Triassic
Type Geological formation
Underlies Garbutt Formation
Buckinghorse Formation
Charlie Lake Formation
Overlies Toad Formation
Thickness up to 417 metres (1,370 ft)[1]
Lithology
Primary Sandstone, siltstone
Other Limestone, dolomite
Location
Named for Liard River
Named by E.D. Kindle, 1946
Region WCSB
Country  Canada

The Liard Formation is a stratigraphical unit of Middle Triassic to Late Triassic age in the Western Canadian Sedimentary Basin.

It takes the name from the Liard River, and was first described in outcrop on the southern bank of the river, near Hell Gate Rapids in the Grand Canyon of the Liard by E.D. Kindle in 1946.[2]

Contents

Lithology

The Liard Formation is composed of dolomitic to calcareous sandstone and siltstone with minor dolostone and bioclastic limestone. [1] the limestone becomes cherty in the south-eastern extent.

Distribution

The Liard Formation Lateral reaches a maximum thickness of 417 metres (1,370 ft) in the Canadian Rockies foothills, in the Williston Lake area.[1] It extends from the Liard River to the Pine River on the eastern edge of the Northern Rockies.

Relationship to other units

The Liard Formation is conformably overlain by the Garbutt Formation and Buckinghorse Formation in the Liard River area, and is disconformably overlain by the Charlie Lake Formation toward the south. It overlays the Toad Formation between Pine River and Williston lake.[1]

It is equivalent to Halfway Formation in the Peace River Country and with the Sulphur Mountain Formation in the southern Canadian Rockies.

References

  1. ^ a b c d Lexicon of Canadian Geologic Units. "Liard Formation". http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:008445. Retrieved 2010-02-01. 
  2. ^ Kindle, E.D., 1946. The Middle Triassic of Liard River, British Columbia, Appendix I. In: A Middle Triassic (Anisian) fauna in Halfway, Sikanni Chief, and Tetsa valleys, northeastern British Columbia. Geological Survey of Canada, Paper 46-1, 2nd ed. 1948.