Английская Википедия:Ishbel Group
The Ishbel Group is a stratigraphic unit of Permian age in the Western Canadian Sedimentary Basin. It is present in the Canadian Rockies of Alberta and British Columbia. First defined by A. McGugan in 1963,[1] it is named for Mount Ishbel of the Sawback Range in Banff National Park, and parts of the group were first described in the vicinity of the mountain at Ranger Canyon and Johnston Canyon.[2]
Lithology
The Ishbel Group is composed of carbonate rocks (limestone and dolomite) and sandstone, with minor chert and siltstone. [3][2] Depositional conditions were similar to those of the Phosphoria Formation to the south in United States.[2]
Paleontology
Among the fossils that have been found in the Ishbel Group are corals, bryozoa, crinoids, and conodonts,[2] as well as productid, chonetid and spiriferid brachiopods, omphalotrochid gastropods, and edestid elasmobranch fish.[4]
Distribution
The Ishbel Group reaches a maximum thickness of up to about 425 metres (1400 ft). It is present in the front ranges of the Canadian Rockies as far north as the Peace River.[3][2]
Subdivisions
| Sub-unit | Age | Lithology | Max. Thickness |
Reference |
|---|---|---|---|---|
| Kindle Formation | Asselian to early Artinskian | siltstone, shale | Шаблон:Convert | [5] |
| Belloy Formation | Permian | limestone, dolomite, and sandstone | Шаблон:Convert | [6] |
| Fantasque Formation | Permian | spicular chert, shale, and siltstone | Шаблон:Convert | [7] |
| Mowitch Formation | Roadian to Wordian | sandstone with gypsum | Шаблон:Convert | [8] |
| Ranger Canyon Formation | Roadian to Wordian | dark chert, silicified sandstone, evaporite minerals | Шаблон:Convert | [9] |
| Ross Creek Formation | late Sakmarian to Artinskian | shaly siltstone, calcareous siltstone, silty carbonate, phosphatic coquinas | Шаблон:Convert | [10] |
| Telford Formation | Asselian to Sakmarian | sandy limestone and dolomite | Шаблон:Convert | [11] |
| Johnston Canyon Formation | late Sakmarian to Artinskian | phosphatic siltstone, calcareous siltstone, and silty limestone and dolomite | Шаблон:Convert | [12] |
| Belcourt Formation | Asselian to Sakmarian | silty dolomite with chert | Шаблон:Convert | [13] |
Relationship to other units
The Ishbel Group is disnconformably overlain by the Spray River Group and unconformably overlies the Tunnel Mountain Formation and the Kananaskis Formation.[3] It is partly equivalent to the Phosphoria Formation of Montana, Idaho, Wyoming, and Utah.[2]
References
Шаблон:Western Canadian Sedimentary Basin
- ↑ McGugan, A., 1963. A Permian brachiopod and fusulinid fauna from Elk Valley, British Columbia, Canada. Journal of Paleontology, v. 37, p. 621-627.
- ↑ 2,0 2,1 2,2 2,3 2,4 2,5 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. Шаблон:ISBN.
- ↑ 3,0 3,1 3,2 Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web
- Английская Википедия
- Geologic groups of British Columbia
- Geologic groups of the Northwest Territories
- Geologic groups of Alberta
- Permian northern paleotemperate deposits
- Страницы, где используется шаблон "Навигационная таблица/Телепорт"
- Страницы с телепортом
- Википедия
- Статья из Википедии
- Статья из Английской Википедии
