It was deposited as an extensive carbonate platform along the western edge of the basin during Late Devonian (Frasnian) time and the reefs of the Cairn Formation subsequently developed on it.

[2][3] The Flume Formation was deposited as limestone, but it was strongly dolomitized during diagenesis, and it now consists primarily of dark grey, medium-to thick-bedded, fine to medium crystalline dolomite.

It includes abundant dark grey chert nodules and stringers, as well as scattered stromatoporoids and Amphipora.

[3] It has been exposed by thrust faulting in the main and front ranges of the Canadian Rockies in a belt extending from the Kakwa Lakes area in northeastern British Columbia to south of the Bow River in Alberta.

It is equivalent in part to the upper Beaverhill Lake Group farther to the east.