| Crowsnest Formation Stratigraphic range: Mid to Upper Albian |
|
|---|---|
Crowsnest Formation exposed in the Crowsnest Pass |
|
| Type | Geological formation |
| Underlies | Blackstone Formation |
| Overlies | Ma Butte Formation |
| Thickness | up to 404 metres (1,330 ft)[1] |
| Lithology | |
| Primary | Air-fall pyroclastic flow, lahar |
| Other | pyroclastic breccia |
| Location | |
| Named for | Crowsnest Pass |
| Named by | G.M. Dawson, 1886[2] |
| Country | Canada |
The Crowsnest Formation, also called the Crowsnest Volcanics, is a well-known outcroping of volcanic rock in southwestern Alberta, Canada. These volcanics were formed about 100 million years ago during the Cretaceous period and is estimated to cover a volume of 209 km3 (50 cu mi). These volcanics are older than the Rocky Mountains and are essentially the eroded remnants of an alkaline volcanic center that was erupted in a fluvial environment.[3]