Plate Tectonics
Pangaea- The History
 A theory brought forth in ______ by one ___________ __________, a
German Scientist.
 The suggestion was that _____________ years prior, there was only one
united continent called _____________ which means “all land.”
 The theory outlines that there was a phenomenon called ___________
_________ that took place 200 million years ago and separated the giant
land mass into the separate continents we see today.
Continental Drift
 Until the _________the theory was not taken seriously by other scientists.
 Some, however, continued the study, only to discover, that ancient rocks
held ____________ ___________ and that there are currents that pass
underneath landmasses that may have been partly responsible for the
separation of Pangaea.
 It has been suggested that the __________ of the earth’s ___________
__________, flips every few thousand years.
 This has already happened resulting in the current position of the earth’s north
and south poles.
Index
Reference
Lutgens
and
Tarbuck
 Notice the direction North America is travelling in order for it to reach it’s
current position
 This is attributed to the change in the ____________ of the earth’s poles.
 Wegener explained his theory by demonstrating that the landforms of the
current continents seemed to ______ together with one another
 He then discovered ___________ ____________ of ________ and
___________ on both continents which he could only explain by deducing that
they must have once been together.
 He also noticed the ___________ ________________ on both continents were
also similar in age.
Plate Tectonics
 A Canadian by the name of _____ ___________ ______________ assisted in
rekindling interest in the theory presented years before the technology was
available to prove it.
 The original theory of continental drift was then expanded into the theory
widely known today as ________________ _____________.
 This theory suggests that the Earth’s outer shell is comprised of _____ plates.
o ______ large
o ______ smaller ones
 Most plates are made up of ____________ and ___________
 Plates are moving over a thin layer of ________ _______ that moves slowly like
melted sugar or plastic.
Eras
In order to break up geological time, geologists have divided the history of
the earth into ________ periods called _________. These eras represent a time of
major sediment deposition and earth movement.
Precambrian Era
 The Precambrian era began an estimates 4 600 000 000 years ago and lasted
for approximately 4 000 000 000 years.
 This means that a whopping 87% of the earth’s geological history consists of
the Precambrian era.
 During this time the only part of Canada that existed was the Canadian Shield
 Processes of folding and faulting are responsible for the heights these
mountains rose to during that time.
 Erosion is responsible for the appearance of the Canadian Shield today which
consists mainly of igneous, metamorphic and some sedimentary rock.
Paleozoic Era
 This era lasted for 325 million years and is the second longest era of the 4
that exist.
 Landforms began to appear when sediments were moved by rivers and
deposited into shallow seas that were compressed into sedimentary rock and
form the bedrock areas of Canada’s provinces
 The belief is that Canada was once near the equator which explains the
production of oil and gas deposits formed by ancient organisms.
 The Appalachian mountains were also believed to have formed during this
time when North America collided with Africa and Europe
 There is evidence of the existence of many complex organisms such as fish,
insects and amphibians.
 Many of the organisms that existed during the Precambrian era became
extinct and no longer exist.
Mesozoic Era
 180 million years
 Marks the break up of Pangaea
 As Pangaea breaks up, North America moves westward and collides with the
pacific plate causing magma to rise, creating granite
 Tectonic forces, late, began to fold the earth’s surface into the Rocky
Mountains on our west coast.
 Organisms such as dinosaurs and other reptiles lived during this era, though
their extinction marks the end of this era.
Cenozoic Era
 Final changes to North America took place during this era
 The Rockies finished their formation with folding and faulting caused by final
movements.
 Volcanoes erupted leaving behind coastal plateaus after the cooling of the
erupted lava.
 For about 2 million years North America, and most of the world, experienced
an ice age where large-scale glacial activity took place which rounded some
of the rough edges formed movement during previous eras.
 The last ice age ended approximately 6000 years ago, though, glaciers are
still found throughout the arctic.
 This era is when mammals are first seen and wen the dinosaurs died out.