|Author:||Charette and Beaudette, 2018|
|Type area:||NTS sheets 35K04, 35F13 and 35K08|
|Geological province:||Churchill Province|
|Geological subdivision:||Ungava Orogen / Narsajuaq Arc|
|Lithology:||Late felsic intrusive rocks|
Table des matières
The Ivitaruq Suite, whose namesake lake is located near one of the most important intrusions of this unit (NTS sheet 35F13), was introduced by Charette and Beaudette (2018) to describe the late, undeformed felsic intrusions. They were previously known in the Narsajuaq Arc as biotite monzogranite veins (St-Onge and Lucas, 1992; St-Onge et al., 1992).
Monzodiorite to monzonite of the Ivitaruq Suite is whitish, coarse grained and massive. Locally, it has a pinkish colour caused by hematitization. Mafic minerals form clusters or are evenly distributed in the matrix. Two facies were described in this unit. The first contains 10 to 20% mafic minerals and varies in grain size. The second contains 20 to 25% mafic minerals, has a speckled texture and contains diorite enclaves in diffuse contact that make up 10 to 15% of outcrops. Coarse granitic bands are observed in diffuse contact. Thin-section observations indicate that the main mafic minerals are hornblende and biotite and that the matrix is not recrystallized.
The Ivitaruq Suite intrusions form kilometre-sized plutons (1-12 km) that are spread northeast of the Naujaat Shear Zone and southwest of the Sugluk Suture. They form oblong masses to the north, stocky ones to the south.
Does not apply.