The Ivitaruq Suite was introduced by Charette and Beaudette (2018) to describe the late, undeformed felsic intrusions (NTS sheets 35K04, 35K08 and 35F13). A strip assigned to this unit has been extended in the NW part of the Sirmiq Lake area (Vanier and Lafrance, 2020). Ces intrusions were previously known in the Narsajuaq Lithotectonic Domain as biotite monzogranite veins (St-Onge and Lucas, 1992; St-Onge et al., 1992).

The unit takes its name from the previous Ivitaruq Lake, now Ivitaaqqut Lake, near of which one of the most important intrusions of this suite is located (sheet 35F13).

Monzodiorite to monzonite of the Ivitaruq Suite is whitish, coarse grained and massive. Locally, it has a pinkish colour caused by hematitization. Ferromagnesian minerals form clusters or are evenly distributed in the matrix. Two facies were described in this unit. The first contains 10-20% mafic minerals and varies in grain size. The second contains 20-25% ferromagnesian 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 ferromagnesian minerals are hornblende and biotite and that the matrix is not recrystallized.