Gog Group

Gog Group Stratigraphic range: Early Cambrian) PreЄ Є O S D C P T J K Pg N
Trace fossils in a slab from the Gog Group.
Type	Group
Sub-units	see text
Underlies	Mount Whyte Formation, Chancellor Group, Snake Indian Formation
Overlies	Miette Group
Thickness	up to 2,180 metres (7,150 ft)
Lithology
Primary	Quartzose sandstone, quartzite, conglomerate
Other	Siltstone, mudstone, limestone, dolostone
Location
Region	Alberta  British Columbia
Country	Canada
Type section
Named by	C.F. Deiss, 1940

The Gog Group is a stratigraphic unit in the Western Canada Sedimentary Basin. It is present in the western main ranges of the Canadian Rockies in Alberta and British Columbia, and in the Cariboo Mountains and in the central Purcell Mountains in southwestern British Columbia. It was named by C.F. Deiss in 1940 for a type locality near Mount Assiniboine.

The Gog Group consists primarily of thick deposits of cross-bedded quartzose sandstone and quartzite, with minor quartzitic conglomerate and sub-arkosic sandstone. It also includes mudstone, siltstone, limestone and dolostone formations. The Gog sediments are thought to have been deposited in shallow marine environments on the subsiding margin of the North American craton (Laurentia).

The Gog Group is subdivided into the following formations:

Trace fossils such as Skolithos, Cruziana, Diplocraterion, Chondrites, Planolites, Rusophycus and others are abundant in the Gog Group sediments, and Early Cambrian trilobites of the genus Olenellus are found in the Peyto Formations limestones at the top of the Group. Small archaeocyathid bioherms have been reported from the base of the Mahato Formation, and archaeocyathids, salterellids, primitive brachiopods and echinoderms have been reported from the Mural Formation.