This
is Rodinia, which
sounds like an European
principality, but is actually the result of collisions between a number
of ancient cratons. The so-called "Grenville Orogeny" gave rise to that
5,000 kilometre long Grenville Range mentioned earlier (here,
represented in red).
The present day continents are
represented on this globe in rough outline: North America (NA); Africa (A); Europe (E);
South America (SA). Obviously, there were other land masses but you may be able to pick some of them out without names?
As far as we know, Rodinia was the first supercontinent situated on planet earth. Notice
that what is now North America was then located very close to the
earth's equator (second line down from the top of the globe)!
This view of the planet was during the Precambrian Period of
time,
850 million years ago. The Canadian Shield in Quebec and Labrador
consistshere of Precambrian rocks which were a product of the Grenville
Orogen, This mountain-bilding episode ended with many continental
fragments welded together to form the supercontinent.
There are only a few places in Maritime Canada which date from this
upheaval" There is a touch of Grenville geologic history at the north
end of the Magdalen Islands and a little bit more at the extreme north
eastern end of Cape Breton Island, Nova Scotia.
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