Cardium Formation
Stratigraphic range in western Canada
The Cardium Formation is a stratigraphic unit of Late Cretaceous age in the Western Canada Sedimentary Basin. It takes the name from the fossilized heart-shaped cockle shells in the family Cardiidae (from Greek καρδίᾱ kardiā, "heart") present. It was first described along the Bow River banks by James Hector in 1895. It is present throughout western Alberta and in northeastern British Columbia, and it is a major source of petroleum and natural gas.
Lithology
The Cardium Formation is composed primarily of beds of massive, fine-grained to conglomeratic sandstone, which are separated by thick layers of shale. The formation is subdivided into the following members, from top to base:
Sturrock Member (sandstone)
Leyland Member (shale)
Cardinal Member (sandstone)
Kiska Member (shale)
Moosehound Member (shale)
Ram Member (sandstone)
In central Alberta, the formation is divided into the Pembina River Member and Cardium Zone.
Distribution
The Cardium Formation was deposited during the Turonian and Coniacian stages of the Late Cretaceous along the western edge of the Alberta Foreland Basin. It extends northward from the Canada-United States border to northeastern British Columbia near Dawson Creek, and eastward from the foothills of the Canadian Rockies into the plains of southern and central Alberta. Beyond there, the sandstones grade into shale. Thickness of Cardium sand varies between 5 and 30 meters in Alberta, Canada.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Aug 10, 2026. The linked authority identifier is Q5038752. Authority coordinates are 51.141, -114.994. 1 of 1 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1895.
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This entry incorporates text from “Cardium Formation” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.