Download Physiographic Regions of North America

Physiographic Regions of North
America
The Coastal Plains
Geology
• Lowland area: Massachusetts to Florida & Golf of
Mexico.
• Swamps & Marshes.
• Constant coastal erosion occurs in this region.
• Average elevation is less than 200m above sea level.
More than half of the region is less than 30m above
sea level!
• In the past, the gradual sinking & erosion of land
allowed the sea to submerge the lower reaches of the
plains.
• The banks and delta of the Mississippi create a wide
belt for agricultural land.
Economy/Industry
• Agriculture (sugar,
cotton, think
plantations).
• Fishing (shell fish:
shrimp, crayfish,
etc.).
• Offshore Oil
Drilling.
Climate
• Varies greatly within the
region.
• In the north: hot, humid
summer & cold, snowy
winters.
• Southern parts of the region
have a subtropical climate,
with mild to warm winters.
• Southern portions are prone
to hurricanes (particularly in
late summer-fall).
Vegetation
• The soils are mainly
sandy, and
vegetation has to
adapt to these soils
and very watery/wet
conditions.
• Marshlands
(Everglades)
• Overgrown swamps
(Bayou)
The Appalachians
Geology
• Stretches from Nfld south
to Alabama and Georgia.
• Fold mountains caused by
2 tectonic plates colliding
together.
• Over 300 million years old.
• Erosion (wind, rain, ice)
has worn them down to
the rolling hills that
dominate the region
today.
Economy/Industry
• Fishing (cod, Atlantic
salmon, lobster, etc.)
• Farming (fruit, potatoes,
dairy, livestock) in the
valleys and plateaus of
the region.
• Mining (coal)
• Natural gas & oil drilling.
Climate
• Maritime climate, which is affected by the influence of the Atlantic Ocean.
• 2 currents that regulate & shape the temperature & climate of the region:
– Labrador Current: brings cold water from the Arctic into the region.
– Gulf Stream: brings warm water from the Gulf of Mexico north into the
region.
Vegetation
• While there are some
coniferous trees in the
region, the landscape and
forests are dominated by
deciduous tree growth.
• There is even some
tourism based on the
brilliant colours of fall in
the Appalachians (fall in
Vermont, NH, etc.) and a
strong maple syrup
industry.
Gr. Lake & St. Lawrence Lowlands
Geology
• Smallest physiographic
region in Canada.
• 50% of Canadians live in
this region.
• Rolling landscape caused
by glaciation (carved by
the movement of ice).
• Flat plains are broken by
hills and deep river
valleys.
Economy/Industry
•
•
•
•
Farming/Agriculture
Mining
Hydroelectricity (Niagara)
Home to 50% of Canada’s
population, so it is also the
financial & industrial
heartland of Canada.
• Manufacturing centre.
• Transportation centreimporting/exporting goods
via the St. Lawrence & Great
Lakes waterways.
Climate
• Humid, Continental
Climate- however, the
climate of the GLSL3 is
moderated by its proximity
to the Great Lakes.
• Results in cool & snowy
winters, but warmmoderately hot, humid
summers (lots of
thunderstorms).
Vegetation
• Fertile soils.
• Was once heavily forested, but
has since been heavily
transformed by human activity
(farming, urban expansion,
logging, etc.)
• Mixture of deciduous &
coniferous trees in remaining
forested areas of the region.
The Canadian Shield
Geology
• Ancient rocks (Precambrian) dominate the landscape
of this region.
• They are the result of volcanism-volcanic activity.
• 2 processes shaped the rocky landscape: mountains
that eroded and metamorphic rock that rose to the
Earth’s surface.
• The rocks have been shaped by glaciation (rocks were
exposed by ice scraping over the thin layer of soil
covering them during the last ice age).
• Glaciation also created many of the lakes that
dominate the region.
• It is the largest physiographic region in Canada.
Economy/Industry
• The many minerals found in
metamorphic rock make the
Shield of Canada’s premier
regions for mining: zinc, copper,
nickel, lead, gold, etc.
• Forestry: pulp/paper, small
lumber.
• Hydroelectric power.
Climate
• Varies, but in general, the region experiences mild/cool
summers and cold winters.
• These become colder and more extreme as the region
extends north towards the Arctic Circle.
Vegetation
• Boreal forest dominates the region (small, mainly
coniferous trees).
• Too rocky with insufficient top soil for many other things
to grow.
The Interior Plains
Geology 1
• The Interior Plains are a
vast sweep of plain, but
are not entirely flat.
• Gently rolling hills and
some deep river valleys.
Geology 2
• The plains were once
covered with huge inland
seas that deposited their
sediment, which resulted
in large layers of
sedimentary rock.
• The breakdown of
sediment and organic
material also resulted in
large reserves of oil and
natural gas, and also
accounts for the fertile
soils of the region.
Geology 3
• In Canada’s Prairie provinces, the plains contain 3 separate
elevations.
• In general, the plains are gently rolling, gradually sloping down from
west to east.
Economy/Industry
• Due to its geological
origins, the soil makes the
prairies ideal for
agriculture (grains) and
Canada’s prairies are
often referred to as the
“Breadbasket of the
World.”
• Oil and Natural Gas
drilling is also a major
industry of the Interior
Plains.
Climate
• Continental Climate:
• Affected by its distance
from the moderating
effects of the oceans.
• e of extremes:
– Long, hot summers.
– Cold winters.
– Little precipitation.
• Farther north,
winters=colder & longer,
and summers= shorter &
cooler.
Vegetation
• The natural vegetation of
the region is grasslandstrees only really grow in
river valleys.
• Heavily altered by human
activity (farming).
• In northern plains, the
boreal forest grows,
gradually becoming
tundra closer to the
Arctic.
The Western Cordillera &
Intermountain Range
Geology
• Cordillera is comprised
of ‘new’ mountains not
yet worn down by
erosion.
• Consist of fold
mountains (caused by
tectonic plate
movement : Pacific &
North American plates),
as well as volcanic
mountains.
Economy/Industry
• Agriculture in rich and
fertile areas: Fraser River
Valley & the Okanagan.
• Forestry: pulp & softwood
lumber.
• Fishing.
• Mining: northern regions
(gold, silver, copper, etc.)
• Natural Gas (northern
regions).
• Tourism.
Climate
• Maritime Climate.
• Varies with latitude
(north to south), but the
west coast is moist &
mild.
• Moderated by the water
of the Pacific Ocean.
• Winters are usually above
freezing.
• Summers are cooler than
the interior of the
continent.
Climate 2
• Valleys = warmer than mountain slopes.
• Windward slopes of mnts.=wetter than leeward
slopes, which are often dry because of the rainshadow effect.
Vegetation
• Vegetation varies from one side of a mountain to another.
• Windward= evergreens such as Douglas firs, western
hemlock, red cedar, etc.
• They grow to tremendous size & age.
• Higher up, the trees = much smaller.
Vegetation 2
• At the tops of mnts, the vegetation becomes
similar to that of the tundra, or it ceases entirely
(treeline).
Vegetation 3
• On the leeward
slopes, grasses
and cactuses grow
in the dry valleys.
• Farther south,
great evergreen
don’t grow, since
the rainfall is less.
The Arctic
Geology
• Much of the Arctic near
the ocean is quite flat.
• The Mountains of the
far north were formed
by folding (when North
America broke away
from Pangea) and are
presently covered by
glaciers.
Economy/Industry
• Mining: diamonds, gold.
• Gas & Oil Drilling.
Climate
• The Arctic climate is
very severe because of
its latitude (far from the
Equator).
• Summers= very short &
not very warm.
• Winters=10 months in
the far north.
• Little precipitation.
Arctic is actually a
desert.
Vegetation
• Not many life forms can grow in the Arctic, beyond lichens.
• Trees do not grow on the tundra due to cold & dry climate,
and also because of the permafrost.
• Small shrubs, mosses, lichens.