Féron Suite
Stratigraphic label: [narc]fer
Map symbol: nAfer

First published: 29 March 2018
Last modified: 5 October 2022














  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.
nAfer2 Diorite, tonalite and monzodiorite
nAfer1 Hornblende-biotite-magnetite quartz monzodiorite, quartz monzonite and monzonite, K-feldspar porphyritic, locally foliated or migmatized
Author(s): Goutier et al., 2021
Age: Neoarchean
Stratotype: Representative outcrops of unit nAfer1 (e.g., dating site 2012-QD-2049) are located along the Sakami River in NTS sheet 33G01. Representative outcrops of unit nAfer2 are found on the south shore of Goose Lake in sheet 33G01.
Type area: NTS sheet 33G01, where this suite covers a large area.
Geological province: Superior Province
Geological subdivision: Opinaca Subprovince
Lithology: Quartz monzodiorite, quartz monzonite and monzonite, diorite, tonalite and monzodiorite ​
Category: Lithodemic
Rank: Suite
Status: Formal
Use: Active




The Féron Suite was defined during the geological mapping work of 2012 in sheets 33G01, 33G02 and 33H04 (Goutier et al., 2021). The mapping work of Gigon and Goutier (2017) in 2015 extended this suite in sheets 33H02 and 33H03. In 2016, Goutier (2018) identified new occurrences of the Féron Suite in sheets 33F01, 33G04 and 33G05. This work also shows that some intrusions of the Bezier Suite belong to the Féron Suite in sheets 33G05 and 33G06. The Casterne Pluton was defined as a result of geological mapping in 2018, during which a new sample for isotopic dating was taken in the NE corner of sheet 33G03 (Côté-Roberge and Goutier, 2019). Unit nAfer3, defined in sheet 33G01 by Goutier et al. (2021) following the work of 2012 has been included in unit nAfer2 (Goutier, 2018). New additions to unit nAfer2 were made by Côté-Roberge et al. (2021) during the 1:50,000 mapping of the Lac Conviac area (sheets 33B02 and 33B07). These intrusions had previously been partly attributed to the Opinaca Intrusive Suite (AOAN2) by Simard and Gosselin (1999).



The Féron Suite is composed of two subunits: 1) quartz monzodiorite, quartz monzonite and hornblende-, biotite- and magnetite-bearing monzonite with locally foliated or migmatized potassium feldspar phenocrysts (nAfer1); and 2) diorite, tonalite and monzodiorite (nAfer2). The Féron Suite units are restricted to the Opinaca Subprovince. This distinguishes them from the Bezier Suite and Bauerman Intrusion units, which straddle the Opinaca and La Grande subprovinces.


Féron Suite 1 (nAfer1): Hornblende-Biotite-Magnetite Quartz Monzodiorite, Quartz Monzonite and Monzonite, K-feldspar Porphyritic, Locally Foliated or Migmatized

Unit nAfer1 consists of a group of quartz monzodiorite, monzodiorite, quartz monzonite and hornblende, biotite and magnetite monzonite. These lithologies are usually K-feldspar porphyritic and intruded by granite. The rock is grey and foliated. The characteristic minerals are hornblende (5-30%), biotite (5-20%) and magnetite (<5%). Outcrops are characterized by K-feldspar ranging in size from 0.5 to 3 cm and representing 5 to 20% of the rock. Locally observed are diopside (15% of the rock on one of the outcrops), hypersthene, titanite and pyrite. The rock is locally altered in hematite, epidote or chlorite. Several fusiform enclaves of various lithologies are found throughout outcrops. Foliated diorite enclaves are decimetric and contain hornblende, biotite and magnetite, while magnetite hornblendite enclaves are centimetric, foliated and finely grained. Finally, centimetric and fine-grained amphibolite enclaves are observed (Goutier et al., 2021). 


Féron Suite 2 (nAfer2): Diorite, Tonalite and Monzodiorite

Unit nAfer2 is an assemblage of diorite, tonalite and monzodiorite whose main intrusion is to the SW of sheet 33G01. The rock is heterogeneous and has light grey patina and fresh surface. It is generally weakly foliated, displaying a low deformation grade, but may be more foliated in places. In thin section, the rock is composed of feldspar (35-70%), quartz (up to 20%), hornblende (10-30%), typically chloritized biotite (5-20%), magnetite and locally hypersthene and clinopyroxene (up to 15%) (Goutier et al., 2021; Côté-Roberge et al., 2021). Accessory minerals include apatite, titanite, epidote, calcite and zircon. Plagioclase is anti-perthitic and is generally moderately to strongly sericitized. Quartz occurs as individual crystals with rolling extinction or as very fine homogeneously distributed inclusions. Hornblende and pyroxenes occur as xenomorphic, locally poikiloblastic crystals and are commonly by-products of the metamorphism of other hornblende or pyroxene crystals. The rocks located in sheet 33G01 are migmatized, as shown in the tonalitic mobilisate. This feature is also present locally in the intrusions of sheet 33B07 (Côté-Roberge et al., 2021). Some fine-grained hornblendite enclaves were observed in the diorite; they contain diopside, magnetite and biotite (Goutier et al., 2021). This unit is cut by decimetric intrusions of coarse-grained pegmatitic granite. 

Thickness and Distribution

The Féron Suite is shown in sheets 33F01, 33F02, 33G01 to 33G06 and 33H02 to 33H04. In this region, the suite covers a total area of approximately 685 km², of which 633 km² (92.4%) is unit nAfer1 and 52 km² (7.6%) is unit nAfer2. Some intrusions belonging to the Bezier Suite were reassigned to the Féron Suite because they were not in direct contact with the rocks of the La Grande Subprovince.

The Féron Suite extends southward in the Opinaca Subprovince in sheet 33B07 as E-W trending nAFer2 intrusions (Côté-Roberge et al., 2021). These intrusions range in size from 500 m to 20 km in length with a maximum width of 2 km. It is likely that they continue to the east and north of sheet 33B07, based on preliminary mapping by Simard and Gosselin (1999).


Isotopic dating was conducted on samples collected in 2014, 2017 and 2018 in the Frégate (nAplf), Casterne (nAcst) and Lakanal (nAlkl) plutons, lithodemes of the Féron Suite. The ages obtained range from 2710.4 to 2701.5 Ma and are considered to be intrusion emplacement ages (Augland et al., 2016; David, 2020a and 2020b). These ages also correspond to minimum sedimentation ages for the Laguiche Basin in their respective areas.

Unit Sample Number Isotopic System Mineral Crystallization Age (Ma) (+) (-) Reference(s)
nAplf 2012-JG-1120A U-Pb Zircon 2710.4 2.4 2.4 Augland et al., 2016
nAlkl 2012-QD-2049A U-Pb Zircon 2702.4 2.7 2.7 David, 2020a
nAcst 2018-MY-6315A U-Pb Zircon 2701.5 2.4 2.4 David, 2020b

Stratigraphic Relationship(s)

The Féron Suite is intrusive in the Laguiche Complex, namely in units nAlgi2a, nAlgi3a and nAlgi4a. It is cut by dykes from the Vieux Comptoir Granitic Suite and diabases from the Mistassini Dyke Swarm and Lac Esprit Dykes. 


Does not apply.


Publications Available through SIGÉOM Examine

AUGLAND, L.E., DAVID, J., PILOTE, P., LECLERC, F., GOUTIER, J., HAMMOUCHE, H., LAFRANCE, I., TALLA TAKAM, F., DESCHENES, P.-L., GUEMACHE, M.A., 2016. Datations U-Pb dans les provinces de Churchill et du Supérieur effectuées au GEOTOP en 2012-2013. MERN, GEOTOP; RP 2015-01, 43 pages.

CÔTÉ-ROBERGE, M., CHARTIER-MONTREUIL, W., HAMEL-HÉBERT, M.-K., BANDYAYERA, D., 2021. Géologie de la région du lac Conviac, sous-provinces d’Opinaca et de La Grande, Eeyou Istchee Baie-James, Québec, Canada. MERN; BG 2022-05, 1 plan.

CÔTÉ-ROBERGE, M., GOUTIER, J., 2019. Géologie de la région du lac Casterne, sous-provinces de La Grande et d’Opinaca, Eeyou Istchee Baie-James, Québec, Canada. MERN; BG 2019-05, 2 plans.

DAVID, J., 2020a. Datations U-Pb dans les provinces du Supérieur et de Churchill effectuées au GEOTOP en 2017-2018. MERN, GEOTOP; MB 2020-05, 29 pages.

DAVID, J., 2020b. Datations U-Pb dans les provinces du Supérieur et de Churchill effectuées au GEOTOP en 2018-2019. MERN, GEOTOP; MB 2020-01, 30 pages.

GIGON, J., GOUTIER, J., 2017. Géologie de la région du lac Richardie, municipalité d’Eeyou Istchee Baie-James. MERN; RG 2016-04, 45 pages, 2 plans.

GOUTIER, J., 2018. Géologie de la région du lac Ewart, sous-provinces de La Grande et d’Opinaca, à l’est de Radisson, Eeyou Istchee Baie-James, Québec, Canada. MERN; BG 2018-10, 2 plans.

GOUTIER, J., GIGON, J., BURNIAUX, P., DION, C., TALLA TAKAM, F., CHARTIER-MONTREUIL, W., BANDYAYERA, D., 2021. Géologie de la région du lac de la Corvette, Eeyou Istchee Baie-James. MERN; RG 2020-01, 69 pages, 1 plan.

SIMARD, M., GOSSELIN, C., 1999. Géologie de la région du lac Lichteneger (SNRC 33B). MRN; RG 98-15, 27 pages, 1 plan.



Suggested Citation

Ministère de l’Énergie et des Ressources naturelles (MERN). Féron Suite. Quebec Stratigraphic Lexicon. [accessed on Day Month Year].




First Publication

Alban Duvernois, M.Sc.; Jean Goutier, P. Geo., M.Sc. (redaction)

Mehdi A. Guemache, P. Geo., Ph.D. (coordination); Pierre Lacoste, 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).

8 novembre 2018