Type Locality:

Along the south side of Great Slave Lake, District of Mackenzie, from Presqu'ile Point to High Point; along the Buffalo River; on the northwest side of the lake at Slave Point; and along the shore between Jones Point and Moraine Point. California Standard Steen River 2-22-117-5W6M, in Alberta, between 1,301.5 and 1,357.0 m (4,270 and 4,452 ft) (Subsurface reference section: Law, 1955a).

Distribution:

The Slave Point Formation is approximately 49 m (160 ft) thick in the vicinity of the type area (Cameron, 1922; Douglas, 1959). The thickness ranges from less than 30 m (100 ft) in northeastern Alberta to more than 120 m (400 ft) around the Celibeta area. The formation is present in the southern Northwest Territories, northeastern British Columbia and northern Alberta.

Locality Data:

WELL 100022211705W600; CHEVRON ZAMA 2-22-117-5. Thickness(m): Typical 49. Interval(m): From 1301.5, To 1357.

Lithology:

The formation consists of light yellowish brown to dark brown limestone, interbedded with finely crystalline dolomite and thin shale laminae. Locally the formation has been recrystallized to coarsely crystalline dolomite. Stromatoporoids are locally abundant along the margin of the formation in northeastern British Columbia and southern Northwest Territories, facing the open marine shale facies (Otter Park Member), and around the eastern and southern edges of the Peace River Arch in northern Alberta. Belyea (1971) interpreted the stromatoporoids occurring in a matrix of lime mudstone, pelletal and skeletal grainstone as sediment-trapping organisms rather than frame-builders.

Relationship:

At Law's (1955a) reference section the Slave Point is unconformably overlain by Upper Devonian Beaverhill Lake or Waterways shales. Braun (1967) demonstrated from subsurface faunal data in the Great Slave Lake and northeastern Alberta areas that much of the basal Upper Devonian is missing due to onlap over the Slave Point formation. Norris (1965) also documented the top unconformity from exposures and fauna in the Great Slave Lake area. In northeastern British Columbia, at the facies front where the Slave Point is partially developed it is overlain by the Otter Park Member (Horn River Formation). Where the Slave Point is fully developed at the facies front the Otter Park is absent, and the Muskwa Member (Horn River Formation) overlies the Slave Point Formation. In northern Alberta the Slave Point may be conformably underlain by the Fort Vermilion Formations or disconformably underlain by the Watt Mountain Formation. The lower Slave Point is equivalent to the Livock River Formation (Crickmay, 1957; Leavitt and Fischbuch, 1968) and the entire Slave Point is equivalent to the lower Swan Hills Formation (Leavitt and Fischbuch, 1968). In northeastern British Columbia, at the facies edge where the Watt Mountain Formation is absent the Slave Point is conformably underlain by the Sulphur Point or Presqu'ile formations.

History:

Cameron (1922) subsequently added to the area of Slave Point outcrop by including exposures on hills north of Sulphur Bay (part of Great Slave Lake) and along the lake shore between Sulphur Point and Mellor Rapids on Buffalo River. These later additions have been reassigned to the Presqu'ile Formation by Douglas (1959). Campbell (1950) described the Slave Point from core holes in the Pine Point area on the south shore of Great Slave Lake. Law (1955a) redefined Campbell's Slave Point and extended the term into the subsurface of northern Alberta, defining the aforementioned reference section at 2-22-117-5W6M.

Other Citations:

Belyea, 1971; Braun, 1967; Cameron, 1918, 1922; Campbell, 1950; Crickmay, 1957; Douglas, 1959; Law, 1955a; Leavitt and Fischbuch, 1968; Norris, 1965.

References:

Belyea, H.R., 1971. Middle Devonian tectonic history of the Tathlina Uplift, southern District of Mackenzie and northern Alberta, Canada; Geological Survey of Canada, Paper 70-14, 38 p.

Braun, W.K., 1967. Upper Devonian Ostracod faunas of Great Slave Lake and Northeastern Alberta, pp. 617-652: in Oswald, D.H. (ed.), International Symposium on the Devonian System, Alberta Society of Petroleum Geologists, Calgary, vol. 2, 1377 p.

Cameron, A.E., 1918. Explorations in the vicinity of Great Slave Lake; Geological Survey of Canada, Summary Report 1917, Part C, pp. 21-28.

Cameron, A.E., 1922. Hay and Buffalo rivers, Great Slave Lake and adjacent country, Northwest Territories; Geological Survey of Canada, Summary Report 1921, Part B, pp. 1-44, contains Map 1585, "Mackenzie River Basin (74, 75, 83, 84,85, 86, 94, 95, 96, 104 P, 105 A P, 106).

Campbell, N.L., 1950. The Middle Devonian in the Pine Point area, Northwest Territories: Proceedings of the Geological Association of Canada, vol. 3, pp. 87-96.

Crickmay, C.H., 1957. Elucidation of some Western Canada Devonian Formations; published by the author, Imperial Oil Limited, Calgary, Alberta, 14 p.

Douglas, R.J.W., 1959. Great Slave and Trout River Map-areas, Northwest Territories: Geological Survey of Canada, Paper 58-11, 57 p.

Law, James, 1955a. Geology of northwestern Alberta and adjacent areas; American Association of Petroleum Geologists (AAPG), Bulletin of the AAPG, vol. 39, no. 10 (October), pp. 1927-1975.

Leavitt, E.M. and Fischbuch, N.R., 1968. Devonian nomenclatural changes, Swan Hills area, Alberta, Canada; Canadian Society of Petroleum Geologists (CSPG), Bulletin of Canadian Petroleum Geology, vol. 16, no. 3 (September), pp. 288-297.

Norris, A.W., 1965a. Stratigraphy of Middle Devonian and older Paleozoic rocks of the Great Slave Lake region, Northwest Territories; Geological Survey of Canada, Memoir 322, 180 p.