Natirnaalik Formation
Stratigraphic label: [ppro]na
Map symbol: pPna

First published: 9 February 2016
Last modified:

Translation of original French

Informal subdivision(s)
Numbering does not necessarily reflect the stratigraphic position.
 
None
 
Author: Lamothe, 2007
Age: Paleoproterozoic
Reference section: None
Type area: NTS sheet 35G07, between Nituk Lake and Natirnaalik Island
Geological province: Churchill Province
Geological subdivision: Ungava Orogen / Ungava Trough / Southern Domain
Lithology: Sedimentary rocks
Type: Lithostratigraphic
Rank: Formation
Status: Formal
Use: Active

Background

Bergeron (1957) and Beall (1960) were the first to mention dolomitic beds near the southern contact of the Cape Smith Belt with Archean bedrock. Taylor (1982) describes it more comprehensively, while Lamothe et al. (1984), Roy (1989) and St-Onge and Lucas (1993) briefly mention the unit.

Description

An allochthonous sedimentary unit located in the basal section of the Southern Domain. It consists of metric dolomite beds, fine-grained and buff-coloured in patina, locally associated with siltstone beds. The rock commonly exhibits quartz veins and concentrated reticular micaceous laminated beds. Too small to be shown on the compilation map, several lenticular beds, ranging in thickness from 30 m to 50 m, were observed near Grunérite Lake (sheet 35H08; Taylor, 1982).

Thickness and Distribution

The Natirnaalik Formation is ~1500 m thick and is located between Nituk Lake and Natirnaalik Island (sheet 35G07). It extends laterally for ~15 km.

Dating

None.

Stratigraphic Relationship(s)

The Natirnaalik Formation structurally lies on phyllites and siltstones of the Nituk Formation.

Paleontology

Does not apply.

References

11 novembre 2019