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Chaumaux Pluton
Stratigraphic label: [ppro]chu
Map symbol: pPchu

First published: 5 December 2017
Last modified: 23 January 2024

 

 

 

  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: Lafrance et al., 2014
Age: Paleoproterozoic
Stratotype: None
Type area: Saffray Lake area (NTS sheet 24G)
Geological province: Churchill Province
Geological subdivision: Baleine Lithotectonic Domain
Lithology: Anorthosite
Category: Lithodemic
Rank: Lithodeme
Status: Formal
Use: Active

Background

The Chaumaux Pluton was introduced into the Saffray Lake area (Lafrance et al., 2014) to define two anorthositic intrusions a few kilometres in diameter.

 

Description

Anorthosite of the Chaumaux Pluton is light grey, massive in appearance and highly granoblastic. It is cut by a network of millimetre to decimetre-wide conjugate fractures, filled with whitish leucocratic material, giving a brecciated appearance with angular anorthosite fragments characteristic of this unit. The rock contains 2-5% ferromagnesian minerals, mainly clinopyroxene, in clusters or concentrated in discontinuous centimetric layers. Clinopyroxene is partially replaced by green hornblende or, more locally, by a chlorite-epidote assemblage. Plagioclase is also slightly sericitized.

 

Thickness and distribution

The Chaumaux Pluton consists of one circular intrusion ~6 km in diameter and a second elliptical intrusion ~6 km by 2 km. It covers an area of ~35 km2 in the north-central portion of the Baleine Lithotectonic Domain (Lafrance et al., 2020).

Dating

The sample taken for dating did not contain zircon.

Stratigraphic Relationship(s)

The nature of contacts with surrounding units was not observed, but it is highly likely that the Chaumaux Pluton cuts migmatites of the Qurlutuq Complex.

Paleontology

Does not apply.

References

Publications available through SIGÉOM Examine

LAFRANCE, I., SIMARD, M., BANDYAYERA, D., 2014. Géologie de la région du lac Saffray (SNRC 24F, 24G). MRN; RG 2014-02, 51 pages, 1 plan.

LAFRANCE, I., VANIER, M.-A., CHARETTE, B., 2020. Domaine lithotectonique de Baleine, sud-est de la Province de Churchill, Québec, Canada: synthèse de la géologie. MERN; BG 2020-07, 4 plans.

Suggested Citation

Ministère de l’Énergie et des Ressources naturelles (MERN). Chaumaux Pluton. Quebec Stratigraphic Lexicon. https://gq.mines.gouv.qc.ca/lexique-stratigraphique/province-de-churchill/pluton-de-chaumaux_en [accessed on Day Month Year].

Contributors

First publication

Isabelle Lafrance, P.Geo., M.Sc. isabelle.lafrance@mern.gouv.qc.ca (redaction)

Mehdi A. Guemache, P.Geo., Ph.D. (coordination); Charles St-Hilaire, P.Geo., M.Sc. (critical review and editing); Céline Dupuis, P.Geo., Ph.D. (English version). 

Revision(s)

Isabelle Lafrance, P.Geo., M.Sc. isabelle.lafrance@mern.gouv.qc.ca (redaction; 06/08/2019) 

Mehdi A. Guemache, P.Geo., Ph.D. (coordination); Simon Auclair, P.Geo., M.Sc. (editing); Céline Dupuis, P.Geo., Ph.D. (English version).

 

 

 

5 février 2020