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.
| 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 |
None
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