Français
 
Landrienne Formation
Stratigraphic label: [narc]la
Map symbol: Ala

First published: 17 July 2018
Last modified:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Translation of original French

 

 

Informal subdivision(s)
Numbering does not necessarily reflect the stratigraphic position.
 
nAla15 Volcanics and felsic volcaniclastics, graphitic mudrock
nAla14 Semi-massive to massive sulphides
nAla13 Magnetite sandstone and wacke
nAla12 Crystal and lapilli felsic tuff
nAla11 Lapilli and block felsic tuff
nAla10 Dacite, rhyodacite and rhyolite
nAla9 Mafic tuff
nAla8  Lapilli and block intermediate tuff
nAla7 Sandstone, graphitic and pyritic turbiditic mudrocks, black claystone
nAla6 Undifferentiated volcaniclastics
nAla5 Volcanics and felsic volcaniclastics, fine-grained graphitic mudrock
nAla4 Andesite
nAla3 Trachyte
nAla2 Basalt, magnetite-chlorite-epidote basaltic tuff, gabbro
nAla1 Chlorite-epidote massive pillow basalt
 
Author:Imreh, 1984
Age:Neoarchean
Reference section: 
Type area:Various volcanic units belonging to this formation are located in NTS sheets 32D08 and 32C05. However, the most representative outcrops are located on forest roads of sheet 32C05.
Geological province:Superior Province
Geological subdivision:Abitibi Subprovince
Lithology:Volcanic and volcano-sedimentary rocks
Type:Lithostratigraphic
Rank:Formation
Status:Formal
Use:Active

 

 

Background

Sharpe (1961) was one of the first to describe these volcanic lithologies during regional mapping, but did not assign them to any particular formation. Imreh (1984) had grouped these and other lithologies under the name “Harricana Group”. This group, which at the time included the Landrienne, Lower Figuery and Higher Figuery formations, was the lithostratigraphic roof of the Héva-Nord Formation (now the Lanaudière Formation). Labbé (1998) reused the name “Landrienne Formation” but gave it a smaller area.

 

Description

The Landrienne Formation is characterized by the preponderance of chloritic basalts, occasionally with magnetite, arranged in massive, pillowed and brecciated flows, as well as large and voluminous dacitic to rhyolitic flows of tholeiitic affinity. East of the Harricana River, massive and pillow basaltic horizons predominate, accompanied by brecciated flows. Gabbroic sills are common. The following units were mapped in the area west of Barraute by Pilote (2017): nAla1, nAla2, nAla5, nAla7, nAla10, nAla11, nAla12, nAla13, nAla14 and nAla15. The remaining units are described based on the work of Sharpe (1961) and McDougall (1965), as well as mapping compilations of the Ministère (MNRF, 2010). 

 

Landrienne Formation 1 (Ala1): Chlorite-Epidote Massive Pillow Basalt

Formation de Landrienne (nAla1)Formation de Landrienne (nAla1)

It is the most commonly encountered unit in the area west of Barraute. Flows have an E-W orientation, a dip varying from 35 to 50° north and reverse polarities. The amphibolite metamorphic facies is reached on the northern contact with the La Corne Batholith, along an N-S axis more than one kilometre long. 

 

 

Landrienne Formation 2 (Ala2): Basalt, Magnetite-Chlorite-Epidote Basaltic Tuff, Gabbro

This unit consists of thin volcanic and volcaniclastic mafic horizons having strong magnetic susceptibility. They are widespread over the entire area of the Landrienne Formation and define several large folds interpreted from their folded trajectory, visible on aeromagnetic surveys (Geological Survey of Canada et al., 2008).

 

Landrienne Formation 3 (Ala3): Trachyte

This unit consists of thin flows of light-grey to white trachyte generally porphyritic and pillowed (McDougall, 1965). It is located in the north-central portion of sheet 32C05 and extends intermittently for approximately 3 km in a direction varying from ENE-WSW to NE-SW.

 

Landrienne Formation 4 (Ala4): Andesite

This unit consists of greenish, porphyritic, massive and pillowed andesitic flows (McDougall, 1965). These flows are generally heavily deformed and sheared. In the southern part of the unit, especially near granite intrusions, volcanics were silicified and carbonatized, while in the NW part they were amphibolitized. This unit consists of the Landrienne Formation dominant lithologies in sheet 32C05-200-0202 (northeast corner) and probably represents the ESE extension of the basalt unit (nAla1) recently mapped by Pilote (2017). Future mapping will clarify this transition or apparent variation in volcanic rock composition between different sheets.

 

Landrienne Formation 5 (Ala5): Volcanics and Felsic Volcaniclastics, Fine-Grained Graphitic Mudrock

Formation de Landrienne (nAla5)Formation de Landrienne (nAla5)Formation de Landrienne (nAla5)Formation de Landrienne (nAla5)

This unit consists of massive, lobed and fragmented dacitic to rhyolitic flows of tholeiitic affinity. This unit, with a maximum thickness of one kilometre, extends over 20 km in an E-W orientation in the northern portion of sheet 32C05-200-0201 and NE portion of sheet 32D08-200-0202. In the NW portion of sheet 32C05-200-02020, this unit extends just over 7 km in an ENE-WSW orientation. Other smaller horizons of this unit continue towards the SW, parallel to trachyte flows (nAla3). Unit nAla5 hosts the Projet 70-Landome mineralized zone.

 

Landrienne Formation 6 (Ala6): Undifferentiated Volcaniclastics

This unit is described in a very general and summary manner as tuffs and andesites by McDougall (1965). These tuffs are usually intermediate in composition and are associated with andesites or trachytes of the same composition. The unit forms irregular flows oriented ENE-WSW to NE-SW in the NW portion of sheet 32C05. In a westerly direction, this unit is 12 km long and 1 km wide, while in the east, it does not exceed 200 m wide for approximately 4 km long. This unit is subparallel to trachyte flows (nAla3).

 

Landrienne Formation 7 (Ala7): Sandstone, Graphitic and Pyritic Turbiditic Mudrocks, Black Claystone

This unit consists of thin sedimentary horizons ranging in thickness from 20 to 60 m. These are relatively persistent along stratification and arranged within unit nAla11.

 

Landrienne Formation 8 (Ala8): Lapilli and Block Intermediate Tuff

This unit consists of a thin horizon oriented NE-SW, 2.5 km long by 50 to 100 m wide. It is located at the SW end of the Landrienne Formation on the north side of Tiblemont Lake (sheet 32C06).

 

Landrienne Formation 9 (Ala9): Mafic Tuff

This unit consists of three horizons of mafic tuffs interbedded in chlorite-epidote basalt (nAla1) horizons. It extends over 1.5 km in a NW-SE direction west of Courville Lake (sheet 32C06).

 

Landrienne Formation 10 (Ala10): Dacite, Rhyodacite and Rhyolite

This unit is located in the southern half of unit nAla5. The largest flow, located in the centre of sheet 32C05-200-0202, follows the general NE-SW orientation of flows in the area west of Barraute.

 

Landrienne Formation 11 (Ala11): Lapilli and Block Felsic Tuff

This fragmentary unit is located on the south side of unit nAla5, at its interpreted stratigraphic summit.

 

Landrienne Formation 12 (Ala12): Crystal and Lapilli Felsic Tuff

This fragmentary unit is located on the north side of unit nAla5, towards its interpreted stratigraphic base.

 

Landrienne Formation 13 (Ala13): Magnetite Sandstone and Wacke

This unit consists of thin sedimentary horizons, ranging in thickness from 5 to 30 m, within the nAla5 unit.

 

Landrienne Formation 14 (Ala14): Semi-Massive to Massive Sulphides

This unit was primarily recognized in drilling in the vicinity of the Marcoland and Projet 70-Landome mineralized zones, within unit nAla5.

 

Landrienne Formation 15 (Ala15): Volcanics and Felsic Volcaniclastics, Graphitic Mudrock

This unit is located in the central-south part of unit nAla5. It consists of massive rhyolitic to dacitic volcanics, block, lapilli and crystal tuffs, as well as thin horizons of graphitic mudrock of limited extent, less than a few hundred metres. Unit nAla15 hosts the Marcoland mineralized zone.

 

Thickness and distribution

The Landrienne Formation is located in the heart of the Barraute region and appears intensely folded. Its actual thickness is difficult to estimate due to the many folds observed and interpreted (Geological Survey of Canada et al., 2008). It is in contact with the Deguisier Formation in the north and the Lanaudière Formation in the south. Some lithologies are less severely folded, particularly those on the north and south edges of the formation. These units continue west in sheet 32C05-200-0201 and east in sheet 32C06-200-201.

 

Dating

Felsic volcaniclastics were dated 2727 ±2 Ma (Labbé, 1998). This age is 8 to 10 My older than volcanics of the Deguisier and Lanaudière formations, immediately adjacent to the north and south. 

Isotopic SystemMineralCrystallization Age (Ma)(+)(-)Reference(s)
U-PbZircon272722Labbé, 1998

Stratigraphic Relationship(s)

The Landrienne Formation occupies a particular geometric situation in sheets 32D08, 32C05 and 32C06. It is in regional-fault contact with volcanics from neighbouring formations, with which it shows a gap in age of almost 10 Ma, which accentuates the importance of these faults. This formation is located in the heart of the Manneville Thrust Zone. Regional schistosity and stratification are subparallel and slightly inclined northward, with angles ranging from 30º to 45°. This formation has a particular structural style involving many synform and antiform folds. Such folds are absent from the formations immediately adjacent to the north and south. These observations raise the hypothesis that this formation represents a tectonic slice carried in the Manneville Thrust Zone.

Paleontology

Does not apply.

References

Author(s)TitleYear of PublicationHyperlink (EXAMINE or Other)
GEOLOGICAL SURVEY OF CANADA –  MINES D’OR VIRGINIA INC. – NORANDA EXPLORATIONCartes géophysiques couleur Mégatem – 32C05. Ministère de l’Énergie et des Ressources naturelles, Québec; DP 2008-06, 5 pages, 4 cartes.2009DP 2008-06
MRNFCartes géologiques du SIGEOM – feuillet 32C. Ministère des Ressources naturelles et de la Faune, Québec; CG SIGEOM32C, 49 plans.2010CG SIGEOM32C
IMREH, L.Sillon de La Motte-Vassan et son avant-pays méridional: synthèse volcanologique, lithostratigraphique et gîtologique. Ministère de l’Énergie et des Ressources, Québec; MM 82-04, 72 pages. 1984MM 82-04
IMREH, L.Cartes géologiques préliminaires au 1/15 840 de l’Abitibi-Est méridional – Quart nord-ouest du feuillet SNRC 32C05. Ministère de l’Énergie et des Ressources, Québec; MB 90-39, 18 pages, 2 plans.1991MB 90-39
LABBÉ, J.-Y.Évolution stratigraphique et structurale dans la région d’Amos-Barraute. Ministère de l’Énergie et des Ressources naturelles, Québec; ET 98-04, pages 5-18.1998

ET 98-04

McDOUGALL, D.J.Quart sud-est du canton de Barraute, comté d’Abitibi-Est. Ministère des Richesses naturelles, Québec; RG 114, 37 pages, 1 carte.1965RG 114
SHARPE, J.I.Rapport préliminaire sur la demie Sud du canton de Figuery et le quart sud-Ouest du canton de Landrienne, comté d’Abitibi-Est. Ministère des Richesses naturelles, Québec; RP 446, 18 pages, 1 carte (échelle 1/24 000).1961RP 446
PILOTE, P.Géologie de la région de Barraute ouest, Sous-Province de l’Abitibi, région de l’Abitibi-Témiscamingue, Québec, Canada. Ministère de l’Énergie et des Ressources naturelles, Québec; CG-2017-05, 1 carte.2017CG-2017-05

 

 

13 novembre 2018