Redknife Formation

The Redknife Formation is divided into the Jean Marie Member (base) and an upper unnamed shale unit. The Jean Marie Member is composed of argillaceous, silty and dolomitic fossiliferous limestone. The carbonates are massive east of Fort Nelson and west of the Alberta border. The upper Redknife consists of calcareous shales with silty limestone and siltstone interbeds. To the south and east, the shales grade into limestone and siltstone, and it becomes dolomitic in the Peace River arch.

The Redknife formation contains common coral and brachiopod fossils.

The Redknife Formation occurs in outcrops in the southern Northwest Territories and in the sub-surface in north-eastern British Columbia, also reaching into north-western Alberta. The maximum thickness of the upper shales is 79 feet (20 m), and the lower carbonates are up to 15 feet (0 m). The Jean Marie Member is found in outcrops south of the Mackenzie River between Kakisa and Blackstone River. It grades westwards into the shale facies of the Fort Simpson Formation. East of the Peace River Arch it turns into the carbonates of the Kakisa Formation.

The Redknife Formation is conformly overlain by the Kakisa Formation and overlies the Tathlina Formation in northern Alberta and the Fort Simpson Formation in British Columbia and Northwest Territories. The Fort Simpson Formation replaces the Redknife Formation to the west. The Redknife Formation can be correlated with the Nisku Formation and upper part of the Ireton Formation in central Alberta.