| Blue Mountain Formation | |
|---|---|
| Stratigraphic range: | |
 Blue Mountain Formation outcropping along the Little Rouge Creek. | |
| Type | Geological formation |
| Sub-units | Rouge River Member |
| Underlies | Georgian Bay Formation |
| Overlies | Lindsay Formation |
| Thickness | Up to 76 metres (250 ft) |
| Lithology | |
| Primary | Shale |
| Other | Limestone, siltstone |
| Location | |
| Region | Southern Ontario, |
| Country | Canada |
| Type section | |
| Named for | Blue Mountain |
| Named by | W. A. Parks |
| Year defined | 1928 |
The Blue Mountain Formation (previously the Whitby Formation) is a geological formation of Upper Ordovician age (Maysvillian Stage), which outcrops in Ontario, Canada from Nottawasaga Bay southeastward to the Toronto area.[1][2]
- ^ "Blue Mountain Formation". WEBLEX Canada. Natural Resources Canada. Retrieved April 17, 2017.
- ^ Béland Otis, C. (2015). Upper Ordovician organic-rich mudstones of Southern Ontario : drilling project results (PDF). Sudbury: Ministry of Northern Development and Mines. pp. 8–9. ISBN 9781460669013.