- Vanguard Formation
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Vanguard Formation
Stratigraphic range: Callovian to OxfordianType Geological formation Sub-units Masefield Shale
Roseray Formation
Rush Lake ShaleUnderlies Mannville Group Overlies Shaunavon Formation Thickness up to 180 metres (590 ft)[1] Lithology Primary Shale, sandstone Location Named for Vanguard, Saskatchewan Named by R.L. Milner and G.E. Thomas, 1954 Coordinates 49°22′N 107°47′W / 49.36°N 107.79°WCoordinates: 49°22′N 107°47′W / 49.36°N 107.79°W Region WCSB, Williston Basin Country 
Canada
United StatesThe Vanguard Formation is a stratigraphical unit of Callovian to Oxfordian age in the Western Canadian Sedimentary Basin.
It takes the name from Vanguard, and was first defined by R.L. Milner and G.E. Thomas in 1954.[2]
Contents
Lithology
The Vanguard Formation is composed of calcareous shale with a median quartzose sandstone. [1]
Distribution
The Vanguard Formation Lateral reaches a maximum thickness of 180 metres (590 ft) in the Williston Basin along the Saskatchewan/Montana border.[1]
Relationship to other units
The Vanguard Formation is unconformably overlain by the Mannville Group and disconformably overlays the Shaunavon Formation.[1]
It is equivalent to the Ellis Group in Montana and North Dakota.
Subdivisions
in south-western Saskatchewan, Vanguard has group status, and includes the following subdivisions (of formation rank):
- Masefield Shale: calcareous shale
- Roseray Formation: quartzose glauconitic sandstone
- Rush Lake Shale: calcareous shale with Gryphaea and Kepplerites ammonite fossils
References
- ^ a b c d Lexicon of Canadian Geologic Units. "Vanguard Formation". http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:015770. Retrieved 2010-01-01.
- ^ Milner, R.L. and Thomas, G E., 1954. Jurassic System in Saskatchewan. In: Western Canada Sedimentary Basin. American Association of Petroleum Geologists, p. 250-267
Western Canadian Sedimentary Basin Hydrocarbon history Depositional Regions Southern Alberta · Central Alberta · Northwestern Alberta Plains · South-central Canadian Rockies foothills · North-east Plains · North-central foothills · Liard River · Fort Nelson · Northern Rocky Mountains · Fort St. John · Saskatchewan · Western ManitobaSaskatchewan Cypress Hills FM · Ravenscrag FM · Frenchman FM · Whitemud FM · Eastend FM · Bearpaw FM · Judith River GRP · Belly River FM · Oldman FM · Foremost FM · Lea Park FM · Pakowki FM · Milk River FM · Colorado GRP · Viking FM · Mannville GRP (Pense FM · Cantuar FM · Success FM) · Vanguard FM · Ellis GRP (Swift FM · Rierdon FM · Sawtooth FM) · Shaunavon FM · Piper FM · Gravelbourg FM · Gypsum Springs FM · Watrous FM · Big Snowy GRP · Madison GRP (Charles FM (Poplar · Ratcliffe · Midale) · Mission Canyon FM (Kisbey SS · Alida · Tilston) · Lodgepole FM - Souris Valley) · Three Forks GRP (Bakken FM · Big Valley FM · Torquay FM) · Saskatchewan GRP (Birdbear FM · Duperow FM) · Manitoba GRP (Souris River FM) · Elk Point GRP (Davson Bay FM · Prairie FM · Winnipegosis FM · Ashern FM) · Interlake FM · Stonewall FM · Stony Mountain FM · Herald FM · Yeoman FM · Winnipeg FM · Deadwood FM · Canadian ShieldCategories:- Stratigraphy of Saskatchewan
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