The term Baudan Complex was first used by Verpaelst et al. (2000) to define a unit of granitic gneiss and granitic intrusions. This unit name was not subsequently used by Simard et al. (2013), Lafrance et al. (2015, 2016) and Charette et al. (2016), who preferred to distinguish regional gneiss zones from late intrusions. The grey gneisses of tonalitic to granitic composition were then assigned to the Ungava Complex. However, in the synthesis of the southeastern part of the Churchill Province (Lafrance et al., 2018), different lithotectonic domains were identified and it appears that the gneisses observed within these different domains are distinct from each other. In the Falcoz Lithotectonic Domain, all grey tonalitic to granitic gneisses have been grouped into the Kangiqsualujjuaq Complex by Mathieu et al. (2018). This complex thus includes some of the outcrops previously assigned to the Baudan Complex by Verpaelst et al. (2000), and those of grey granitic gneisses, but excludes the later intrusive rocks which have been assigned to the Qarliik Suite (Mathieu et al., 2018), and the porphyroclastic monzogranite outcrops which now represent the Baudan Suite as defined by Mathieu et al. (2018). Porphyroclastic monzonite outcrops located in the eastern part of the Falcoz Lithotectonic Domain and previously assigned to the Inuluttaliq Suite have also been grouped into the Baudan Suite (Lafrance and Vanier, 2022).

Description

Baudan Suite 1 (nAban1): Porphyroclastic Monzogranite

Thickness and Distribution

The Baudan Suite covers an area of ~387 km² and is concentrated in the northeast sector of the Falcoz Lithotectonic Domain (Lafrance and Vanier, 2022). It forms multi-kilometre klippes that extend between 5 and 40 km in a general NW-SE axis.

Dating

An age of ~2623 Ma was obtained in a sample described as a gneissic porphyritic monzogranite in the Koroc River area (Verpaelst et al., 2000). A second age of ~2673 Ma appears to confirm the Neoarchean emplacement of this unit. However, the inclusion of this outcrop in the Baudan Suite remains uncertain due to the strong deformation of the sample, which was collected within the Falcoz Shear Zone (flzSZ).

Stratigraphic Relationship(s)

The Baudan Suite is part of the ancient rocks of the Falcoz Lithotectonic Domain. The relationships with the other Archean rocks were not observed in the field. It is cut by granitic intrusions of the Qarliik Suite.

Paleontology

Does not apply.

References

Publications available through SIGÉOM Examine

Suggested Citation

Contributors