Unit Name: Nauyat Formation
Unit Type: Lithostratigraphic
Rank: Formation
Status: Formal
Usage: Currently in use
Age Interval: Neohelikian ? (1269 - 1000 ma)
Age Justification: The volcanic unit has been dated as 903 +/- 140 m.y., which suggests a Neohelikian age (Blackadar, 1970).
Province/Territory: Nunavut
Originator: Blackadar, 1970.
Type Locality:
Coastal cliff east of Admiralty Inlet and north of Moffet Inlet, northern Baffin Island.
Distribution:
The lower, clastic and volcanic member, not everywhere present, is up to 150 m thick including volcanic flows up to 60 m thick. The upper, volcanic member is up to 100 m thick in the Adams sound - Elwin River area (Jackson et al., 1978b), 90 m on Bylot Island (Jackson and Davidson, 1975) and may exceed 600 m in the Moffet Inlet area (Blackadar, 1970).
Lithology:
Two members, the lower comprising clastic and volcanic rocks, and the upper, volcanic rocks. The lower member consists mainly of nonmarine (fluvial), white to brown quartz arenites that locally are marked by fining-upward cycles; basic volcanic flows are interbedded. The upper member consists of volcanic flows, fine-grained and amygdaloidal, with columnar jointing and rarely pillowed at the base. The composition is that of tholeiitic plateau basalts with alkalic affinities.
Relationship:
The formation rests unconformably on gneisses of the Aphebian base-ment, the surface of which has considerable local relief. The Nauyat Formation forms the lowest unit of the Eqalulik Group and is conformably overlain by the Adams Sound Formation.
History:
The Nauyat Formation includes the 'Lower Quartzite' and 'Volcanic' Members of early reports (Blackadar, 1956; Lemon and Blackadar, 1963).
References:
Blackadar, R.G., 1956. Geological reconnaissance of Admiralty Inlet, Baffin Island, Arctic Archipelago: Geological Survey of Canada, Paper 55-6, 25 p.
Blackadar, R.G., 1970. Precambrian geology northwestern Baffin Island, District of Franklin: Geological Survey of Canada, Bulletin 191, 89 p.
Jackson, G.D. and Davidson, A., 1975. Bylot Island Map-area, District of Franklin; Geological Survey of Canada, Paper 74-29, 12 p.
Jackson, G.D., Ianelli, T.R., Narbonne, G.M., and Wallace, P.J., 1978b. "Upper Proterozoic sedimentary and volcanic rocks of northwestern Baffin Island"; Geological Survey of Canada, Paper 78-14, 15 p.
Lemon, R.R.H. and Blackadar, R.G., 1963. "Admiralty Inlet area, Baffin Island, District of Franklin"; Geological Survey of Canada, Memoir 328, 84 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: H.H.J. Geldsetzer; P.H. Davenport
Entry Reviewed: No
Name Set: Lithostratigraphic Lexicon
LastChange: 25 Sep 2007