Unit Name: Aston Formation
Unit Type: Lithostratigraphic
Rank: Formation
Status: Formal
Usage: Currently in use
Age Interval: Proterozoic (2500 - 542 ma)
Province/Territory: Nunavut
Originator: Blackadar, 1963a.
Type Locality:
Locality V of Blackadar (1963 , Geol. Surv. Canada, Map 1098 A), approximately 9 km southeast of Aston Bay, northwestern Somerset Island.
Distribution:
Exposed on northwestern Somerset Island, southwest of Aston Bay; about Savage Point on western Prince of Wales Island and on Pandora and Prescott Islands (Dixon et al., 1971). The formation is locally up to 1400 m thick. It thickens both eastward and westward south of Parry Channel and may thicken northward, as well (Kerr, 1977).
Lithology:
Grey, yellow and red quartzites with minor interbedded siltstone, black and red shales, dolostone, stromatolitic dolostone, and pebble conglomerates.
Relationship:
The Aston Formation rests unconformably on a crystalline basement of mixed gneisses dated at 1650 - 1850 m.y. (McGlynn, in Stockwell et al., 1970). The formation has been intruded by two sets of basic dykes and sills; the first set is truncated by the unconformity beneath the overlying Hunting Formation, and the second penetrates both the Hunting and Aston formations and is truncated by the unconformity underlying the Cambrian Lang River Formation (Kerr, 1977).
Remark:
First Published: Geological Survey of Canada, Map 19-1959.
Other Citations:
Blackadar 1963a; Tuke et al., 1966; Blackadar, 1967; Dixon et al., 1971; Kerr, 1977.
References:
Blackadar, R.G., 1963a. Somerset Island between Aston Bay and Creswell Bay, pp. 143-150: in Geology of the north-central part of the Arctic Archipelago, Northwest Territories (Operation Franklin), Geological Survey of Canada, Memoir 320, 671 p.
Kerr, J. Wm., 1977. Cornwallis Fold Belt and the mechanism of basement uplift; Canadian Journal of Earth Sciences, vol. 14, no. 6 (June), pp. 1374-1401.
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: F. Alexander
Entry Reviewed: Yes
Name Set: Lithostratigraphic Lexicon
LastChange: 06 Mar 2009