L5 - Geologic History of Canada Handout

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Evolution of Canada’s Landforms
We will now take a look at the geologic history of Canada. It has taken millions of year for the
forces of plate tectonics and erosion to shape Canada’s landscape to what is has become. All
of these forces remain active on the Canadian landscape today…what do you think Canada will
look like in another 100 million years?!?!?!?!?
1. Precambrian Era (4.6 billion years ago)
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Precambrian rocks from (Canadian Shield)
Canadian Shield is worn down by erosion
Canada is the remains of a
from Pangea
Volcano is
rock – hard, volcanic rock, rich in minerals from the mantle
2. Early Paleozoic Era (450 million yeas ago)
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Canada near equator with abundant life (
and
form)
Pangea formed
– the breaking down of the volcano occurs over billions of years
Eroded rock fragments becomes layers of built up land –
rock
Sediments and dead plant matter accumulate to the east, west, north, and south of equator
3. Late Paleozoic Era (250 mya)
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Mountains are created
Fish, amphibians and plants start to evolve
4. Mesozoic and Cenozoic Era (225 mya – present)
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Erosion continues, building up sedimentary layers
Plate pushes against
Plate creating mountains in the east,
leaving a low lying area between the mountains and the eroded volcano – Appalachian
Mountains
North American Plate and Pacific Plate collide. The
Plate slips under sediments,
pushing land p to create fold mountains in the west, leaving a low lying area between the
mountains and the eroded volcano – BC coastal mountains are formed followed by the Rocky
Mountains (
)
Inland seas in the
provinces (Alta, Sask., Man.)
Ice age moves soil off shield to
(e.g. S. Ontario)
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