|Author:||Charette and Beaudette, 2018|
|Stratotype:||Ivitaruq Lake, now Ivitaaqqut Lake, NTS sheet 35F13 (type locality)|
|Type area:||NW part of the Ungava Peninsula|
|Geological province:||Churchill Province|
|Geological subdivision:||Ungava Orogen / Narsajuaq Lithotectonic Domain|
|Lithology:||Felsic intrusive rocks|
Table des matières
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.
The Ivitaruq Suite intrusions form kilometre-sized plutons (1-12 km) that are spread NE of the Naujaat Shear Zone and SW of the Sugluk Shear Zone. They form oblong masses to the north, stocky ones to the south.
Does not apply.
CHARETTE, B., BEAUDETTE, M. 2018. Geology of the Cape Wolstenholme Area, Ungava Orogen, Churchill Province, Southeast Ivujivik, Quebec, Canada. MERN. BG 2018-03, 1 plan.
VANIER, M.-A., LAFRANCE, I. 2020. Geology of the Sirmiq Lake Area, Ungava Orogen, Nunavik, Quebec, Canada. MERN. BG 2020-02, 1 plan.
ST-ONGE, M. R., LUCAS, S. B., PARRISH, R. R. 1992. Terrane accretion in the internal zone of the Ungava orogen, northern Quebec. Part 1: tectonostratigraphic assemblages and their tectonic implications. Canadian Journal of Earth Sciences; volume 29, pages 746-764. https://doi.org/10.1139/e92-064
ST-ONGE., M. R., LUCAS, S. B. 1992. New insight on the crustal structure and tectonic history of the Ungava Orogen, Kovik Bay and Cap Wolstenholme, Quebec. In Current Research, Part C, Canadian Shield. Geological Survey of Canada; Paper 92-1 C, pages 31-41. https://doi.org/10.4095/132842
Ministère de l’Énergie et des Ressources naturelles (MERN). Ivitaruq Suite. Quebec Stratigraphic Lexicon. http://gq.mines.gouv.qc.ca/lexique-stratigraphique/province-du-superieur/suite-ivitaruq_en [accessed on Day Month Year].
Mehdi A. Guemache, P. Geo., Ph.D. (coordination); Mélina Langevin, GIT, B.Sc. (critical review); Simon Auclair, P. Geo., M.Sc. (editing); Céline Dupuis, P. Geo., Ph.D. (English version); Yan Carette (HTML editing).
Isabelle Lafrance, P. Geo., M.Sc. firstname.lastname@example.org (redaction)
Mehdi A. Guemache, P. Geo., Ph.D. (coordination); Benoit Charette, P. Geo., M.Sc. (critical review); Simon Auclair, P. Geo., M.Sc. (editing); Céline Dupuis, P. Geo., Ph.D. (English version); André Tremblay (HTML editing).