Blaa Mountain Group

Unit Name: Blaa Mountain Group
Unit Type: Lithostratigraphic
Rank: Group
Status: Formal
Usage: Currently in use
Age Interval: Middle Triassic - Late Triassic (245 - 199.6 ma)
Age Justification: Biostratigraphy. Based on ammonite and pelecypod fossils, palynomorphs, as well as the intertonguing relationships of the Roche Point and Pat Bay formations with adjacent units of known ages (Embry, 1984c).
Province/Territory: Northwest Territories; Nunavut

Originator: Embry, 1984c

Type Locality:

Type section for the Blaa Mountain Formation on northern Ellesmere Island (Troelsen, 1950).

Distribution:

Within the Sverdrup Basin, Canadian Arctic Archipelago (Embry, 1984c).

Lithology:

Basinal sediments characterized by shale and siltstone, with minor coarse grained interbeds (Embry, 1984c).

Relationship:

Contains the Murray Harbour, Hoyle Bay, and Barrow formations. Equivalent strata that are sand dominated and located in the southern and eastern margins of the Sverdrup Basin are assigned to the Schei Point Group (Embry, 1984c).

History:

The Blaa Mountain Formation was defined by Troelsen (1950). Subsequent stratigraphic work (Souther, 1963;Tozer, 1961, 1963b, c,) further defined the formation. It was elevated to group status by Embry (1984c).

Remark:

Formerly the Blaa Mountain Formation.

References:

Embry, A.F. 1984c. The Schei Point and Blaa Mountain Groups (Middle-Upper Triassic), Sverdrup Basin, Canadian Arctic Archipelago; Geological Survey of Canada, Paper 84-1B, pp. 327-336.

Souther, J.G., 1963. Geological traverse across Axel Heiberg Island from Buchanan Lake to Strand Fiord; pp. 426-448: in Fortier, Y.O. et al. , Geology of the north-central part of the Arctic Archipelago, N.W.T. (Operation Franklin), Geological Survey of Canada

Tozer, E.T., 1963b. Northwestern Bjorn Peninsula, pp. 363-370: in Fortier, Y.O. et al. Geology of the north-central part of the Arctic Archipelago (Operation Franklin), Geological Survey of Canada, Memoir 320, 671 p.

Tozer, E.T., 1963c. Blind Fiord, pp. 380-385: in Fortier, Y.O. et al., Geology of the north-central part of the Arctic Archipelago (Operation Franklin), Geological Survey of Canada, Memoir 320, 671 p.

Troelsen, J.C., 1950. Contributions to the geology of Northwest Greenland, Ellesmere Island, and Axel Heiberg Island: Meddelelser om Gronland, vol. 149, no. 7.

Source: GEOLOGICAL SURVEY OF CANADA, CALGARY
Contributor: G.E. McCune
Entry Reviewed: No
Name Set: Lithostratigraphic Lexicon
LastChange: 29 Sep 2010