Transcript Canada`s Landform Regions

Canada’s Landform Regions
Cross section p. 31-34
landform – a natural feature of a land surface
Vocabulary
• Erosion – the process of the wearing down of the
earth’s landscape
• Peneplain – ‘almost a plain’
• Lakescape – landscape with many lakes
• Badlands – area of hills and deep gullies formed by
erosion, with sparse vegetation
• Moraine - an accumulation of earth and stones carried
and finally deposited by a glacier
• Plateau – elevated area of fairly level land
• Continental plate – shallow ocean floor bordering a
continent
• Heartland – region with a large, concentrated
population considerable manufacturing, and influence
over surrounding regions.
Precambrian Shield
aka
Canadian Shield
Covers almost half of Canada – 4 800 000 km²
• Name pre cambrian indicates the rocks were in place
before the Cambrian period of the earth
• Canada’s oldest rocks
• Only the roots of mountains remain
• Erosion has reduced the area to a peneplain
• Today elevation is seldom over 600m
Precambrian bedrock of the Canadian Shield rising out of Reindeer Lake, on the border
between northeastern Saskatchewan and northwestern Manitoba.
• Landscape is very rugged, like a lakescape
• Lakes numerous, Pleistocene ice ages added to the
shape of the region (saucer shape), tends to drain
towards Hudson Bay
Athabasca Basin – northwestern Saskatchewan, northeastern Alberta
• Tourist playground
• Many minerals because of metamorphic rocks
• Lowest population of Canada’s four major southern
landform regions; population widely scattered; most
live in or near major mining areas or forestry centers
• Not exclusively Canadian
The Great Plains
• Extends over central Canada, from near the OntarioManitoba border to the Rockies
• Vast majority of the population of the Prairie Provinces
and Northern Territories live here
• Almost entirely in Canadian Territory
• Formed after the Shield – the sedimentary rocks on the
plains were deposits from the Shield
• Shallow seas invaded North America during the early
eras. Shells formed part of the thick strata of limestone
and chalk. Material from the Cenozoic Era later eroded
adding to more layers.
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Three different levels
Region grows higher as it approaches Cordillera
Deep valleys cut by rivers
Covered by glaciers in the last ice age, there are
scattered morainic features, also contains badlands
Manitoba
• Not a source of metallic minerals; however, natural
oil and gas collected in region’s porous rocks
Saskatchewan
Grazing
Oil
Grain
Potash is
mined to be
used in the
manufacture
of fertilizer
and other
chemical
products.
• Rich soil is the greatest physical resource; Canada’s
breadbasket
• Soils developed from glacial deposits
• Settlement pattern of region determined by agriculture
The Western Cordillera
• Forms the western boundary of the Great Plains
• Separates most of British Columbia’s population from
the rest of Canada
• Highest most rugged of the regions
• Larger interior plateau between two mountain ranges:
Columbia Mountains (west side; oldest of the two
regions) and Rocky Mountains (east side)
Bugaboo Glacier Provincial Park, British Columbia
• Both ranges formed mostly of folded sedimentary rock;
both were once sea floors
Upper Arrow Lake, British Columbia
• Rockies folded because of the movement of the North
American plate toward the Pacific Plate – 65 million
years ago; erosion has affected the mountains
Mountain Range that extends from British Columbia into New Mexico
• Volcanic activity nearby because the North American
Plate rides over the Pacific Plate just off the coast of
B.C.
• Interior Plateau
highland area; not as
rugged as the
mountains; resembles
area of low mountains
• Provides good
farmland
• Sparsely populated;
people concentrated
in the valleys and
troughs
Okanagan Valley, British Columbia
Vancouver, British Columbia
• Largest cities are on the coast – Vancouver
The Great Lakes/St. Lawrence Lowlands
of the four southern landform regions – yet
largest population – close to three fifths of Canada’s
population
• Smallest
• Known as nation’s
heartland – Ontario and
Quebec
•Forms one region, yet is
separated by projection of
the Shield into eastern
Ontario
• More heavily populated
because most favoured
landform region in Canada
• Excellent base for agriculture and settlement
• Reaches farther south than any other region; most
pleasant climate
Flowerpot Island, Ontario
• Close to trading partner USA
• Region was submerged under inland seas; sediments
were deposited from the shield and Appalachians; seas
drained away and left material – developed into
sandstone, limestone, and shale
• Rock in place is old sea floors – glacier moraine
• Ice formed Great Lake basins
Mont St-Hilaire, east of Montreal
• St Lawrence Lowlands have a top layer of sediment
laid down by the Champlain Sea – sea flooded inland
covering entire lowland area
• Sea receded leaving behind excellent deposits which
formed into excellent soil
The Appalachians
• Sediments were laid down in the Appalachian region; fold
mountains formed due to the collision of the North
American and European plates – early in the Mesozoic era
• Geologists believe that Atlantic Canada was once
joined to northern Europe
• Appalachians continue out onto the continental shelf –
submerged
• Volcanism occurred as the plates collided – volcanoes
erupted and magma intruded into the sedimentary
layers; considerable faulting occurred; ie Cape Breton
Highlands (above)
Prince Edward Island
• Erosion has reduced much of the Canadian Appalachian
to a peneplain – as on the shield
• Glacial moraines are common
Prince Edward Island
• Terrain generally rugged; population concentrated in
areas favoured with deep soil and level relief
• Larger cities are located on deep harbours
• Great variety of rocks – mineral base also varied
• Igneous, sedimentary and metamorphic rocks provide
mineral resources
The Northern Mountains and
Hudson Bay Lowlands
• Least known, least settled and economically, the least
used of all regions
Barbeau Peak, Nunavut
• Mountains result of folding and faulting
• Mountains are found on the northernmost islands of the
Arctic archipelago. Some are quite high. The highest,
Barbeau Peak, reaches 2616 m.
Hudson Bay Lowlands, Manitoba
• Two separate areas: Hudson Bay Lowlands and
Lowlands on the more southern islands of the Arctic
archipelago
• Very low population