Rae Craton
Ungava Peninsula
The Ungava Peninsula, situated on the northeast portion of the Canadian Shield, is where the Rae Province connects with the Superior Province. The area is composed of Archean rocks (ca. 2.7-2.9 Ga) from the Douglas Harbour Domain (see Superior craton).
The Rae Craton Archean rocks are overlain by Paleoproterozoic supracrustal sequences (ca. 1.8-2.1 Ga) and intruded by Paleoproterozoic diabase dykes (ca.2.0-2.2 Ga).
The supracrustal rocks comprise nappes that form part of the Ungava and Labrador troughs. In the zone east of the Labrador Trough axis, the Paleoproterozoic deformation reworked the Archean rocks of the Douglas Harbour Domain, as well as the Paleoproterozoic diabase dykes.
The metamorphic conditions which parallel the deformation increase from west to east and from middle amphibolite to granulite facies. U-Pb isotope analyses of zircon yield secondary ages around 1790 Ma. These results are interpreted as the age of metamorphism and indicate a reactivation of the northeastern margin of the Superior Province during a Paleoproterozoic tectono-metamorphic event, resulting from probable continental collision. (Madore, 2001).
See also
- Canadian Shield
- North American Craton
References
- Madore, L., and Y. Larbi. (2001) "Regional structural character of the northeastern Ungava Peninsula: Connection between the Rae and Superior provinces." St. John's 2001 Technical Programme SS2: Tectonic Integration of Circum-Superior Orogens. Online Abstract: