Type Locality:

Exposures in the vicinity of the Headless Range, on a tributary to Meilleur Creek and at the first canyon on the South Nahanni River are considered typical (= map-unit 21 of Douglas and Norris, 1960b).

Distribution:

It is about 61 m (200 ft) in the type area and maintains about this thickness throughout the southern Franklin Mountains and parts of the Mackenzie Mountains. It ranges up to 302 m (990 ft) in the Thundercloud Range. It occurs in the southern Franklin Mountains and parts of the Mackenzie Mountains.

Locality Data:

Thickness(m): Maximum 302, Typical 61.

Lithology:

Argillaceous, thin-bedded, grey, cryptocrystalline to fine-grained limestone, interbedded with calcareous shale. Generally recessive, except in the glacier map-area southwest of Redstone.

Relationship:

In the Camsell Bend map-area, the Headless Formation overlies the Manetoe Formation and may interbed with it; in the Whittaker and Iverson ranges it overlies the Funeral; in the northwestern part of Root River and Virginia Falls map-areas it overlies the Landry Formation. It is overlain throughout much of the area by the Nahanni Formation. It corresponds to map-unit 21 of Douglas and Norris (1960b). In the Virginia Falls area the Headless Formation is the facies equivalent of the Nahanni Formation. Law (1971) suggested the possibility that shales at the top of the formation might best be assigned to a new unit and also indicated that the Headless Formation was laterally equivalent to the lower Hume Formation and may be laterally equivalent to parts of the Chinchaga Formation.

Other Citations:

Blusson, 1971; Braun, 1978; Chatterton , 1974; Douglas and Norris, 1963; Gabrielse, 1967a; Gabrielse et al., 1965; Gabrielse et al., 1973; Lenz, 1973; Noble and Ferguson, 1971; Uyeno and Mason, 1975.

References:

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.

Braun, W.K., 1978. Devonian ostracodes and biostratigraphy of western Canada; pp. 259-288: in Stelck, C.R. and Chatterton, B.D.E. (eds.), Western and Arctic Canadian Biostratigraphy, Geological Association of Canada Special Paper no. 18, 602 p.

Douglas, R.J.W. and Norris, D.K., 1960b. Virginia Falls and Sibbeston Lake map-areas, Northwest Territories (95F and 95G); Geological Survey of Canada, Paper 60-19, 26 p.

Douglas, R.J.W. and Norris, D.K., 1961. Camsell Bend and Root River map-areas, Northwest Territories; Geological Survey of Canada, Paper 61-13, 36 p.

Douglas, R.J.W. and Norris, D.K., 1963. Dahadinni River and Wrigley map-areas, District of Mackenzie, Northwest Territories; Geological Survey of Canada, Paper 62-33, 34 p.

Gabrielse, H., 1967a. Tectonic evolution of the northern Canadian Cordillera; Canadian Journal of Earth Sciences = Journal Canadien des Sciences de la Terre, vol. 4, no. 2, pp. 271-298.

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.

Law, James, 1971. Regional Devonian geology and oil and gas possibilities, upper Mackenzie River area; Canadian Society of Petroleum Geologists (CSPG), Bulletin of Canadian Petroleum Geology, vol. 19, no. 2 (June), pp. 437-484.

Lenz, A.C., 1973. Nadiastrophia from the Headless Formation (Eifelian), Mackenzie Mountains, District of Mackenzie, Northwest Territories; Canadian Journal of Earth Sciences = Journal Canadien des Sciences de la Terre, vol. 10, no. 9, pp. 1460-1464.

Noble, J.P.A. and Ferguson, R.D., 1971. Facies and faunal relations at edge of early mid-Devonian carbonate shelf, south Nahanni River area, N.W.T.; Canadian Society of Petroleum Geologists (CSPG), Bulletin of Canadian Petroleum Geology, vol. 19, no. 3 (September), pp. 570-588.

Uyeno, T.T. and Mason, D., 1975. New Lower and Middle Devonian conodonts from Northern Canada; Journal of Paleontology, vol. 49, no. 4, pp. 710-723.