Unit Name: Weatherall Formation
Unit Type: Lithostratigraphic
Rank: Formation
Status: Formal
Usage: Currently in use
Age Interval: Middle Devonian - Late Devonian (397.5 - 359.2 ma)
Province/Territory: Northwest Territories; Nunavut

Originator: Tozer and Thorsteinsson, 1964.

Type Locality:
16 km east of the east arm of Weatherall Bay, Melville Island.

Distribution:
Recognized on Melville, Prince Patrick and Banks Islands; recorded thicknesses range from 990 m to 1,445 m.

Lithology:
Interbedded shale, siltstone and very fine-grained sandstone arranged in coarsening-upward cycles 3 to 30 m thick. In the uppermost portion of the formation, white crossbedded sand-stone forms the lower part of fining-upward cycles. Various fossils including pelecypods, brachiopods, crinoids, cephalopods, trilobites and corals occur with the formation.

Relationship:
Conformably overlies the Cape de Bray Formation. On Melville Island the Weatherall is conformably overlain by the Hecla Bay Formation, on Prince Patrick and Banks Islands, by the Parry Islands Formation.

History:
The Weatherall Formation as used by Tozer and Thorsteinsson (1964) included strata now assigned to the Blackley and Cape de Bray Formations; these strata are lithologically dissimilar from the type Weatherall.

Other Citations:
Tozer and Thorsteinsson, 1964; Klovan and Embry, 1971; Embry and Klovan, 1976; Miall, 1976a.

References:
Embry, A.F. and Klovan, J.E., 1976. The Middle-Upper Devonian clastic wedge of the Franklinian Geosyncline; Bulletin of Canadian Petroleum Geology, vol. 24, no. 4, pp. 485-639.
Klovan, J. E. and Embry, A.F., III, 1971. Upper Devonian stratigraphy, northeastern Banks Island, N.W.T.: Bulletin of Canadian Petroleum Geology, vol. 19, no. 4, pp. 705-729.
Miall, A.D., 1976a. Proterozoic and Paleozoic geology of Banks Island, Arctic Canada; Geological Survey of Canada, Bulletin 258, 77 p.
Tozer, E.T. and Thorsteinsson, R., 1964. Western Queen Elizabeth Islands, Arctic Archipelago: Geological Survey of Canada, Memoir 332, 242 p.

Source: CSPG Lexicon of Canadian Stratigraphy, Volume 1, Arctic Archigelage (District of Franklin); R.L. Christie, A.F. Embry, G.A. Van Dyck (editor)
Contributor: A.F. Embry
Entry Reviewed: Yes
Name Set: Lithostratigraphic Lexicon
LastChange: 29 Jan 2009