[1] Its type section is located in the Spray River gorge at the southern end of Sulphur Mountain.

[1] The Sulphur Mountain Formation was deposited on the continental shelf along the western margin of the North American craton,[6] which at that time was part of the supercontinent of Pangaea.

[4] It consists primarily of grey to rusty brown dolomitic and calcareous quartz siltstone, with interbeds of silty sandstone, silty dolomite, mudstone, shale, carbonaceous shale, and minor fine-grained quartz sandstone.

[4][5] The flaggy siltstones of the Vega Member have been quarried as building stone in the Canmore area.

[1][15] Although localized deposits of granular phosphate are present at the base of the Whistler Member, they lie within Jasper National Park and are protected from development.