Its deposition spanned the time interval from the lower Campanian through to the upper Maastrichtian, between approximately 80 and 68 Ma.

[4] The Wapiti Formation does not produce many fossils due to its limited surface exposure and accessibility, although two Pachyrhinosaurus bone beds have been productive.

[5] The Wapiti Formation consists of interbedded sandstones, siltstones, shales and mudstones, with thin conglomerates, coal seams and bentonite beds.

[3] The Wapiti Formation was deposited in inland fluvial and floodplain environments, with local areas of lacustrine sediments.

[6] The sandstones were deposited mainly in fluvial channel environments, with siltstones, carbonaceous shales and coals accumulating in overbank settings.