Early Proterozoic orogenic activity adjacent to the Hopedale block of southern Nain Province

• Main Authors: Ermanovics, Ingo, Ryan, Bruce
• Format: Article in Journal/Newspaper
• Language: English
• Published: Geological Association of Canada 1990
• Subjects: Makkovik; Nain
• Online Access: https://journals.lib.unb.ca/index.php/GC/article/view/3708

The Hopedale block of the southern Archean Nain Province forms a wedge between the Early Proterozoic Makkovik and Churchill provinces. Lower Proterozoic supracrustal rocks, deposited on the Hopedale block following intrusion of tholeiitic dykes ca. 2200 Ma, were reworked at amphibolite facies, and thrust westward against undeformed portions of the block during orogeny in the Makkovik Province. The Makkovik/Hopedale block structural boundary is marked by a late, greenschist-facies dextral shear. By contrast, the boundary between the Hopedale block and the Churchill Province to the west is a fault zone that separates lower Proterozoic supracrustal rocks, deposited on a protocontinent of Churchill Province rocks, from fundamentally different rocks of the Nain Province. The intensity of Early Proterozoic deformation and metamorphism rises progressively from sub-greenschist fades in the Hopedale block to granulite fades in the interior of the Churchill Province.