Unit Name: Souris Valley Beds
Unit Type: Lithostratigraphic
Rank: Formation
Status: Formal
Usage: Currently in use
Age Interval: Kinderhookian (359.2 - 348 ma)
Age Justification: Brown (1952b) reported a brachiopod fauna in this unit from a well in south western Manitoba and Brindle (1960a) reported a brachiopodal fauna from several wells in southeastern Saskatchewan, most of which had affinities to uppermost Kinderhookian faunal assemblages.
Province/Territory: Manitoba; Saskatchewan; North Dakota

Originator: Saskatchewan Geological Society, 1956.

Type Locality:
Souris Valley Oil Gordon White No. 1 well, in Lsd. 5, Sec. 14, Twp. 1, Rge. 28WPM, Manitoba, between 1107 and 1283 m (3632 and 4210 ft).

Distribution:
At the type section the Souris Valley Beds are 176 m (577 ft) thick and in southeastern Saskatchewan they range from 122 to 170 m (400 to 558 ft). The unit can be traced from the type well to about Rge. 22W2M, where the argillaceous marker bed defining the upper contact undergoes a facies change and is no longer recognizable. In addition it can be traced southward from the type well into North Dakota. Its northern and eastern limits are an erosional edge as the interval is progressively truncated in those directions.

Locality Data:
Thickness(m): Minimum 122, Maximum 170, Typical 176.

Lithology:
At the type locality the Souris Valley Beds comprise a dark grey, sparsely fossiliferous, thin bedded basin-type sequence of argillaceous limestones, calcareous shales, and chert. To the east and north of the type well the unit loses its argillaceous nature and becomes more shelf-like, containing abundant fossils and oolitic intervals.

Relationship:
The contacts with the underlying Bakken Formation and overlying Tilston Beds are conformable. The unit is equivalent to the Lodgepole Formation of southwestern Manitoba (Stanton, 1958) and with the Bottineau Interval of North Dakota (Bjorlie and Anderson, 1978). Kent (1974) correlated this interval with the lower part of the Strathallen Beds of southwestern Saskatchewan.

Other Citations:
Bjorlie and Anderson, 1978; Brindle, 1960; Brown, 1952; Edie, 1958; Fuller, 1956; Fuzesy, 1960; Kent 1974; McCabe, 1959; Ower, 1953; Porter, 1955; Saskatchewan Geological Society, 1956; Stanton, 1958; Thomas, 1954.

References:
Bjorlie, P.F. and Anderson, S.B., 1978. Stratigraphy and depositional setting of the Carrington shale facies (Mississippian) at the Williston Basin. Montana Geol. Soc., 24th Ann. Conf. Williston Basin Symp., p. 165-176
Brindle, J.E., 1960a. Mississippian Megafaunas in Southeastern Saskatchewan; Saskatchewan Department of Mineral Resources, Saskatchewan Industry and Resources (SIR) Report no. 45, 107 p., 29 plates, 4 figures (one in pocket).
Brown, R.A.C., 1952b. Carboniferous stratigraphy and palaeontology in the Mount Greenock area, Alberta; Geol. Surv. Can. Memoir 264.
Kent, D.M., 1974. A stratigraphic and sedinnentological analysis of the Mississippian Madison Formation in southwestern Saskatchewan. Saskatchewan Dept. Min. Res., Rept. 141.
Saskatchewan Geological Society, 1956. Report of the Mississippian Names and Correlations Committee.
Stanton, M.S., 1958. Stratigraphy of the Lodgepole Formation, Virden-Whitewater area, Manitoba. In: Jurassic and Carboniferous of western Canada; Goodman, A.J. (Ed.). Amer. Assoc. Petrol. Geol., p. 372-90.

Source: CSPG Lexicon of Canadian Stratigraphy, Volume 4, western Canada, including eastern British Columbia, Alberta, Saskatchewan and southern Manitoba; D.J. Glass (editor)
Contributor: D.M. Kent
Entry Reviewed: Yes
Name Set: Lithostratigraphic Lexicon
LastChange: 07 Apr 2009