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Chapter 6
Regional Geography of
North America
P 160-180
Introduction
 North
America is
made up of a
variety of
landscapes
 Earth is 4.5 billion
years old
 Three layers: crust,
mantle, and core
Earth’s Layers

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The crust is a thin layer of rock about 5-35 km
thick
Broken up into large and small pieces – plates
Under the crust is the mantle which is molten
rock known as magma
The centre of the earth is the core that is hot,
and dense, and solid in the centre
Heat of the core is responsible for heating the
mantle
Magma moves, causing the plates of the
crust to move or break
Forming of Continents
 From
600 to 225
million years ago,
the continents of
North America,
Africa, and Europe
were joined
 Tectonics created
the Canadian
Shield 2 billion
years ago
Fold Mountains
 When
two plates are
pushed together
over millions of years,
the rock layers
crumple up and form
fold mountains
 e.g. Rocky Mountains
and Appalachian
Mountains
Volcanic Mountains


When the crust
breaks while it is
folding, molten rock
pushes through and
creates volcanic
mountains
E.g. Canadian Shield
and Cascade
Mountains
Ice Ages
 Ice
Ages eroded geographic features
 Prolonged period of cooling about 60
million years ago
 By 2.5 million years ago, glaciation of the
northern hemisphere widespread
 During last ice age (25 000-10 000 years
ago), glaciers covered most of North
America
 Glaciers are literally rivers of ice
Glaciers in North America
Effects of Glaciation
 Melted
water drained into earth’s oceans
 Some of the melted water was blocked
by debris the glaciers had scraped away
 Formed lakes
 Deposits of silt laid down  flat, bare land
like the prairies
 Scraped the rocks bare, leaving very little
soil Canadian Shield
 Left mounds of debris  hills
North American Settlers
 Before
European settlement, North
America was filled with forests, swamps,
and deserts
 First Nations peoples did not really
change the environment much
 European settlers to North America felt
that the environment should be modified
to suit their needs
Some final definitions
 Topography:
the shape of the land
 Climate: the prevailing conditions of
temperature and precipitations
 Vegetation: the plants that grow naturally
in an area
8 Geographic Regions of
North America

Information taken from
Heidi Robinson’s
powerpoint on SlideShare
Appalachian Region
Topography
 Travels
from Newfoundland through,
Maritime provinces through, U.S. as far as
Alabama and Georgia
 Many different mountain ranges
 About 300,000,000 years old
 Lots of continual erosion
 Consists of fertile plateaus and river valleys
 Coal, oil and gas can be found in
sedimentary rock
Climate
 Heavily
affected by ocean currents
 Grand Banks had lots of fish which was
the main attraction for European
explorers and settlers
Vegetation
 Mixed
coniferous (evergreen) and
deciduous (shed leaves annually) trees
The Coastal Plains
Topography
 Extends
from Cape Cod along Atlantic
coast which includes, Florida then going
westward and traveling along Gulf Of
Mexico continuing to Mexico
 Average elevation is below 200m above
sea level
 Mostly flat
 Swamps and marches that give
transportation routes and agricultural land
Climate
 North
– cold and snowy winters/hot and
humid summers
 South – subtropical climate, mild to warm
winters

Hurricanes – late summer to early
winter
Vegetation
 Mainly
sandy - some natural vegetation
has adapted to this type of soil
 Lush jungles (in Mexico)
 Originally pine forests
The Great Lakes – St. Lawrence
Lowland
Topography

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includes triangle created by lakes Huron ,
Ontario and Erie
Smallest of all the geographic regions of
North America
Several escarpments (Niagara Falls)
Has two separate parts
Rolling landscape
Created by glaciation
Climate
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Humid continental climate
Due to the Great Lakes
Winter – cool to cold
Summer – warm to hot
Vegetation
 Very
fertile
 Maple, Beech, Hickory and Black Walnut
trees
 Mixed forests – deciduous and coniferous
The Interior Plains
Topography
 Bordered
on the east by the Canadian
Shield and on the west by the Rocky
Mountains
 Bordered to the north by the Arctic
Ocean and to the south by the Gulf of
Mexico
 Not entirely flat
 Gentile rolling hills and deep river valleys
 600-1500m above sea level on average
 Canada’s “Bread Basket of the World”
Climate
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Continental climate
In the heart of the continent
Away from the influence of oceans
Climate of extremes
Long hot summers
Cold winters
Little precipitation
In the north the winters are colder and longer, in
the south the summers are warmer
Arctic climate in the north with extremely long
winters and short summers
Vegetation
 Grasslands
in this prairie area
 Boreal forest in the northern regions with
tundra towards the Arctic
The Canadian Shield
Topography

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More than 2 billion years old
Great volcanic mountains that have been
levelled by erosion
Geographic foundation of Canada
Only in 2 of the US States
Barren rock left by glaciation
Chaotic pattern of rivers, lakes, swamps and
muskeg
About 100-500m above sea level on average
Most rivers flow towards Hudson or James Bay
Climate

As you travel north the winters get longer
and colder, and the summers get shorter
and cooler
Vegetation
 Boreal
forest covers most of the area
 North of the tree line, no trees are able to
grow due to the very short growing
season, little precipitation and permafrost
The Western Cordillera
Topography
 Along
the west coast of North America
 Range after range of mountains
 New mountains not yet worn by erosion
 The Rocky Mountains form the continental
divide that determines the flow of most
rivers
Climate
 Maritime
climate
 West coast is moist and mild
 Winters usually above freezing with cooler
summers that the interior of the continent
 Warm valleys
 Rain-shadow
Vegetation
 Varied
 Forests
and deserts
 Most of the earths forms of vegetation
can be found here
The Intermountain Region
Topography
 Located
in U.S. and Canada which falls
between the Rocky Mountains, the
Cascades and Sierra Nevada
 Area of high plateaus
 Isolated mountains
 Streams and rivers never make it to the
ocean (not in all cases)
 Lots of cattle ranching
Climate
 Affected
by location and elevation
 Winters can be cool and wet or hot and
dry
Vegetation
 Sparse
grasslands to semi-desert or desert
plants
 Pine forests in the higher elevations
The Arctic
Topography
 Combination
of lowlands and mountains
 Flat near the ocean
 Mountains in the far north
 Mostly covered by glaciers
Climate
 Very
severe
 Very far from the equator
 Winter lasts for 10 months at a time
 Summer is very short
 Actually a desert because of so little
precipitation
 Area is dominated by permafrost
Vegetation
 Very
few life forms
 Trees cannot grow on the tundra
 Small shrubs, mosses and lichen can grow