Unit Name: Keele Formation
Unit Type: Lithostratigraphic
Rank: Formation
Status: Formal
Usage: Currently in use
Age Interval: Hadrynian (1000 - 542 ma)
Age Justification: Cryptalgal laminites, incipient stromatolites and hemispherical stromatolites.
Province/Territory: Northwest Territories

Originator: Gabrielse et al., 1973; defined with two reference sections in Eisbacher, 1978b.

Type Locality:
Westward dipping Proterozoic succession, 30 km (19 mi) west-southwest of Coates (=Little Dal) Lake, Glacier Lake map area, central Mackenzie Mountains (62° 37'N, 125° 17'30"W).

Distribution:
Thickness in outcrop ranges from a few tens to possibly 900 m (2,953 ft). Extends from central MacKenzie Mountains for 500 km (311 mi) northwestward.

Lithology:
Cyclic shallow-water sandstones, with shale and siltstone beds, oolitic or laminated limestone dolostone cycles (upwards-shoaling), olistostromes with megaclasts of limestone and dolostone and matrix of siliciclastic siltstone and particulate dolostone, conglomerate with extra-basinal crystalline clasts, and a capping 'teepee' - dolomite of great regional extent make up this varied unit. Locally it consists of three members - a lower carbonate, a middle shale, and an upper olistostrome member.

Relationship:
Grades downward to Twitya Formation with the base placed at the first carbonate unit above shale and sandstone of the Twitya Formation. Local unconformities occur at or near the base (Blusson, 1971; Gabrielse et al., 1973). The top of the formation is well defined by a light buff or grey, dense dolomite in sharp contact with the conformably overlying Sheep bed Formation. The Keele Formation corresponds to map-unit 8 of Upitis (1966) and Gabrielse et al., (1965).

History:
Gabrielse et al. (1973) placed the Keele Formation above the Rapitan Group. Eisbacher (1978b) assigned it to the Rapitan Group whereas Yeo et al. (1978) restrict the Rapitan Group to the Sayunei and Shezal formations and place the Twitya and Keele in the Hay Creek Group.

Other Citations:
Aitken et al., 1973a; Eisbacher, 1976, 1977, 1978; Yeo, in press; Yeo et al., 1978.

References:
Aitken, J.D., Macqueen, R.W., and Foscolos, A.E., 1973a. A Proterozoic sedimentary succession with traces of copper mineralization, Cap Mountain, southern Franklin Mountains, District of Mackenzie (95 O), in, Report of Activities, Part A: April to October 1972; Geological Survey of Canada, Paper 73-1, Part A, pp. 243-246.
Blusson, S.L., 1971. Sekwi Mountain map-area, Yukon Territory and District of Mackenzie (105 P); Geological Survey of Canada, Paper 71-22, 17 p. + "A" Series Map 1333A, Geology, Sekwi Mountain, Northwest Territories - Yukon Territories; Scale: 1:250 000.
Eisbacher, G.H., 1976. Sedimentology of the Dezadeash Flysch and its implications for strike-slip faulting along the Denali Fault, Yukon Territory and Alaska; Canadian Journal of Earth Sciences = Journal Canadien des Sciences de la Terre, vol. 13, no. 11 (November 1976), pp. 1495-1513.
Eisbacher, G.H., 1977. Tectono-stratigraphic framework of the Redstone copper belt, District of Mackenzie: Geological Survey of Canada, Report of Activities, Paper 77- 1A, p. 229-234.
Eisbacher, G.H., 1978b. Re-definition and subdivision of the Rapita Group, Mackenzie Mountains; Geological Survey of Canada, Paper 77-35, 21 p.
Gabrielse, H., Blusson, S.L., and Roddick, J.A., 1973. Geology of the Flat River, Glacier Lake and Wrigley Lake map-areas, District of Mackenzie and Yukon Territory; Geological Survey of Canada, Memoir 366 (Parts I and II), 421 p.
Gabrielse, H., Roddick, J.A., and Blusson, S. L., 1965. Flat River, Glacier Lake and Wrigley Lake, District of Mackenzie and Yukon Territory, 95E, 95L and 95M (Report and Maps 35-1964, 36-1964, and 37-1964); Geological Survey of Canada, Paper 64-52, 30 p. + Preliminary Map 35-1964, Geology, Flat River, Yukon Territory - District of Mackenzie, Scale 1:253 440 or 1 inch to 4 miles, Preliminary Map 36-1964, Geology, Glacier Lake, District of Mackenzie, Scale 1:253 440 or 1 inch to 4 miles, and Preliminary Map 37-1964, Geology, Wrigley Lake, District of Mackenzie, Scale 1:253 440 or 1 inch to 4 miles.
Upitis, U., 1966. The Rapitan Group, southwestern Mackenzie Mountains, Northwest Territories: unpublished M.Sc. thesis, McGill University, Montreal, 70 p.
Yeo, G.M., Delaney, G.D., and Jefferson, C.W., 1978. Two major Proterozoic unconformities, Northern Cordillera: Discussion, in, Current Research, Part B, III: DIscussions and Communications, Blackadar, R.G., Griffin, P.J., Dumych, H. and Neale, E.R.W. (Eds. and Compilers); Geological Survey of Canada, Paper 78-1B, pp. 225-230.

Source: CSPG Lexicon of Canadian Stratigraphy, Volume 2, Yukon Territory and District of Mackenzie; L.V. Hills, E.V. Sangster and L.B. Suneby (editor)
Contributor: L.V. Hills; G.H. Eisbacher
Entry Reviewed: Yes
Name Set: Lithostratigraphic Lexicon
LastChange: 24 Nov 2009