Gladstone Formation
The Gladstone Formation is a stratigraphic unit of Early Cretaceous (Aptian) age in the Western Canada Sedimentary Basin.[2] It is present in the foothills of southwestern Alberta and is named for outcrops along Gladstone Creek, a tributary of the Castle River south of the Crowsnest Pass.[1][3]
| Gladstone Formation | |
|---|---|
| Stratigraphic range: | |
| Type | Geological formation |
| Unit of | Blairmore Group, Luscar Group |
| Underlies | Beaver Mines Formation, Moosebar Formation |
| Overlies | Cadomin Formation |
| Thickness | up to about 180 metres (590 ft) |
| Lithology | |
| Primary | Sandstone, siltstone, mudstone |
| Other | Limestone, coal |
| Location | |
| Region | Alberta |
| Country | Canada |
| Type section | |
| Named for | Gladstone Creek |
| Named by | J.R. McLean[1] |
Stratigraphy and lithology
The Gladstone Formation is a unit of the Blairmore and Luscar Groups. The lower portion of the formation consists of fine-grained sandstone interbedded with siltstone, mudstone and claystone. The upper portion consists of limestone beds and coquinas of fresh water shells, interbedded with calcareous mudstone, siltstone and fine-grained sandstone. Thin coal beds are present in northern areas.[1][3]
Thickness and distribution
The Gladstone Formation is present in the foothills of southwestern Alberta from the Gladstone Creek area south of the Crowsnest Pass, northward to the Kakwa River area. It has a maximum reported thickness of about 180 metres (590 ft) north of the North Saskatchewan River.[3]
Environment of deposition and paleontology
The Gladstone sediments were derived from erosion of mountain ranges to the west, transported eastward by river systems, and deposited in a variety of floodplain environments.[4] They contain a fossil fauna of mainly fresh water bivalves, gastropods, ostracods, and charophytes.[3]
Relationship to other units
The Gladstone Formation rests conformably on the Cadomin Formation. It is overlain by the Beaver Mines Formation in the south, and by the Moosebar Formation in the north. It is equivalent to the Gething Formation of northeastern British Columbia. The upper calcareous portion is equivalent to the Ostracod Beds of the Alberta plains.[1][3][5]
References
- ^ a b c d McLean, J.R. 1980. Lithostratigraphy of the Lower Cretaceous coal-bearing sequence, foothills of Alberta. Geological Survey of Canada, Paper 80-29.
- ^ Mossop, G.D. and Shetsen, I. (compilers), Canadian Society of Petroleum Geologists and Alberta Geological Survey (1994). . Archived from the original on 2013-08-14. Retrieved 2013-08-01.
{{cite web}}: CS1 maint: multiple names: authors list (link) - ^ a b c d e Glass, D.J. (editor) 1997. Lexicon of Canadian Stratigraphy, vol. 4, Western Canada including eastern British Columbia, Alberta, Saskatchewan and southern Manitoba. Canadian Society of Petroleum Geologists, Calgary, 1423 p. on CD-ROM. ISBN 0-920230-23-7.
- ^ Taylor, D.R. and Walker, R.G. 1984. Depositional environments and paleogeography in the Albian Moosebar Formation and adjacent fluvial Gladstone and Beaver Mines formations, Alberta. Canadian Journal of Earth Sciences, vol. 21, p. 698-714.
- ^ Alberta Geological Survey, 2013. (PDF). Archived from the original (PDF) on 2015-09-25. Retrieved 2016-10-07.