Middle Cambrian rocks of the Ghost River area west of Calgary, Alberta, are correlatives of the type Cathedral, Stephen, Eldon and Pika formations near Field, British Columbia. Sandstones and shales of the Lower Cathedral Formation are thought to be lithologic equivalents of a transgressive diachronic Middle Cambrian unit in the subsurface and the Lower Cambrian St. Piran Formation near Field. Younger carbonate units represent deposition in deeper water, at a greater distance from the eastern shoreline.

The Ghost River Formation is the western shoreline deposit of the transgressing Devonian sea and rests unconformably on Middle Cambrian strata. Younger Devonian, Mississippian, Pennsylvanian, Triassic and Upper Cretaceous units are similar to those described from other areas in western Alberta. Jurassic, Lower Cretaceous and lower Upper Cretaceous rocks are not exposed in the area.

Gently dipping Palaeozoic formations outcrop above the McConnell fault in a broad doubly-plunging syncline that is overridden on the west by the Costigan fault which underlies a westerly dipping homocline in Palaezoic and Triassic rocks. Locally, erosion has removed much of the McConnel thrust sheet to expose the junction of the two faults. Formation of the Panther River thrust sheet below the McConnell fault folded the latter and formed the End Mountain syncline and an anticline to the west. The Costigan thrust and Ghost River tear faults resulted from the folding of this thrust sheet and are complexly related. West of the Costigan fault the Exshaw thrust is overlain by a homocline of Mississippian and younger beds.

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Topography is controlled to a marked degree by structure and massive Middle Cambrian limestone which form steep-walld canyons in the eastern part of the area.

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