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Qaaneq Complex
Stratigraphic label: [ppro]qaa
Map symbol: pPqaa
 

First published: 23 October 2020
Last modified:

 

 

 

  DISCLAIMER: This English version is translated from the original French. In case of any discrepancy, the French version shall prevail. 

Informal subdivision(s)
Numbering does not necessarily reflect the stratigraphic position.
 
None
 
Author: Beaudette et al., 2020
Age: Paleoproterozoic
Stratotype: None
Type area: Northern part of the Parent Lake area (NTS sheet 35G11)
Geological province: Churchill Province
Geological subdivision: Ungava Orogen
Lithology: Metamorphic sedimentary rocks
Category: Lithodemic
Rank: Complex
Status: Formal
Use: Active
Related unit(s)

None

Background

The Qaaneq Complex was introduced by Beaudette et al. (2020) to individualize metamorphic sedimentary rocks located east of the Ammaluttuq Fault in the northern part of sheet 35G11.

 

Description

The Qaaneq Complex consists of paragneiss containing small centimetric quartzitic meta-arenite layers. Paragneiss are brownish beige in altered surface and whitish grey in fresh exposure. Meta-arenite is light grey or brownish beige in altered patina and fresh exposure. Paragneiss is commonly fine grained, foliated and of variable composition. Millimetric to decimetric compositional banding is evidenced by variations in the main mineral contents, including biotite, a quartz-feldspar assemblage and locally garnet or muscovite. Plagioclase accounts for 5 to 60% of lithology. It is partially to totally replaced by non-oriented sericite flakes or by a sericite-epidote ± titanite assemblage. Anhedral quartz in isolated crystals or in clusters accounts for 20% to 75% of the volume of the rock. It is generally fine, even grained or granoblastic, as evidenced by triple point junctions between crystals. Undulatory extinction is commonly observed in samples with coarser crystals. Quartz is also observed as rounded inclusions in biotite crystals.

Ferromagnesian minerals account for 5% to 40% of the paragneiss composition and consist of, in order of abundance, fine to medium biotite, actinolite, hornblende and chlorite. Muscovite is not a diagnostic mineral of Qaaneq Complex paragneiss; it represents 0% to 25% of the rock. On average, 2% subhedral pink garnet is observed in layers richer in mica. The poikiloblastic texture of garnet is evidenced by numerous inclusions of biotite, quartz and opaque minerals. Microscopically, the arrangement of these inclusions indicates a slight rotation of syn-kinetic origin of garnet in some samples. The foliation is marked by the preferential orientation of minerals, with the exception of late sericite sheaves and some epidote and titanite crystals, interpreted as post-kinetic. Macroscopic samples of quartzitic meta-arenite have a composition largely dominated by light grey quartz crystals. Light beige specimens contain feldspars replaced by sericite; brownish specimens may contain iron oxides.

 

Thickness and Distribution

The Qaaneq Complex extends over 8 km and is oriented NW-SE. Its apparent thickness does not exceed 1.5 km.

Dating

None.

Stratigraphic Relationship(s)

The Qaaneq Complex is possibly cut by the Qikirtalialuk and Iqiat suites.

Paleontology

Does not apply.

References

Publications Available Through SIGÉOM Examine

BEAUDETTE, M., BILODEAU, C., MATHIEU, G. 2020. Geology of the Parent Lake Area, Ungava Orogen, Nunavik, Quebec, Canada. MERN. BG 2020-04, 1 plan.

 

Suggested Citation

Ministère de l’Énergie et des Ressources naturelles (MERN). Qaaneq Complex. Quebec Stratigraphic Lexicon. http://gq.mines.gouv.qc.ca/lexique-stratigraphique/province-de-churchill/complexe-de-qaaneq_en [accessed on Day Month Year].

Contributors

First publication

Carl Bilodeau, P. Geo., M.Sc. carl.bilodeau@mern.gouv.qc.ca; Mélanie Beaudette, GIT, B.Sc. melanie.beaudette@mern.gouv.qc.ca (redaction)

Mehdi A. Guemache, P. Geo., Ph.D. (coordination); James Moorhead, P. Geo., M.Sc. (critical review); Simon Auclair, P. Geo., M.Sc. (editing); Céline Dupuis, P. Geo., Ph.D. (English version); Ricardo Escobar Moran (HTML editing).

 
20 novembre 2020