But that red rock, to my untrained-amateurish eyes, looks like the same red rock that covers most of Northern Ontario too. That is... the rock dubbed The Canadian Shield.
It is, indeed, part of the Canadian Shield; as this includes some of the largest known areas of exposed Archaean rock (meaning rock more than 2,500 million years old) in the world. Found a nice map on a blog about geology. The grey bits are surface exposures of rocks formed in the Archaean. These fossils(?) were found just on the eastern edge of Hudson bay.