physical geography of the u.s. & canada chapter 5 section 1
TRANSCRIPT
Physical Geography of the Physical Geography of the U.S. & CanadaU.S. & Canada
Chapter 5 Section 1Chapter 5 Section 1
- U.S. & Canada cover 7 million sq. miles
- 12% of Earth
Western FeaturesWestern Features• Pacific Ranges
– Formed by colliding plates (Pacific & N.A.)
– Sierra Nevada, Cascade Range, Alaska Range, and Coastal Mountains (in Canada)
Mt. McKinley (Alaska Range) = tallest peak
in N.A. at 20,320 feet
Western FeaturesWestern Features
• Great California Valley– alluvial valley
– out produces any other region in fruit & vegetable production
In Between LandformsIn Between Landforms
• Dry basins and plateaus fill area between Pacific Ranges and Rockies – Why?– rain shadow effect from Pacific Ranges
In Between LandformsIn Between Landforms
• Great Basin Region: area of low land surrounded by mts.– Great Basin, Mojave,
Sonoran, & Chihuahuan Deserts
In Between LandformsIn Between Landforms– Death Valley:
• hottest & lowest (282 ft. below sea level) place
in N. Am.• dancing rocks
phenomenon
In Between LandformsIn Between Landforms
• Columbia Plateau-– Created by lava
seeping thru cracks• Flood basalt
– Eventually part of crust sank into space left by lava
In Between LandformsIn Between Landforms• Colorado Plateau-
– Created by tectonics and erosion (Colo. River)
– Grand Canyon @ southern end
– Walls as steep as 6,000 ft
Hoover DamHoover Dam
• Built on Colorado River b/w Arizona and Nevada (1931-1935)
• What is purpose of building dam?– to provide irrigation, flood
control, and hydroelectric-power
Rocky MountainsRocky Mountains• Formed by collision of
N. A. & Pacific plates
• Stretch more than 3,000 miles from New Mexico to Alaska
• Some peaks are more than 14,000 ft tall
• Series of ranges (cordilleras)
Rockies in Alberta, Canada
Continental DivideContinental Divide
• Divide = high point or ridge that determines the direction that rivers flow– E - toward Arctic Ocean
& Atlantic Ocean– W - into the Pacific
Ocean
RiversRivers• Main rivers that have headwaters in Rockies
– Colorado, Columbia, Rio Grande, Mackenzie, Missouri
Interior LandformsInterior Landforms
• US: between Rockies and Appalachian
• Canada: between Rockies and Canadian Shield
Interior LandformsInterior Landforms• Great Plains (aka Interior/High Plains*)
– Start at 6,000 ft gradually slope down about 10 ft/mile from W to E
– E of Rockies: extend 300-700 miles across center of region
– “Breadbasket” of the US
(Wheat Belt)
*depends on source*
Interior Landforms Interior Landforms • High Plains: primarily W of the 100th
meridian– W of meridian= 10-20 inches of rain (semi-
arid); good for rangeland• Rain shadow from Rockies
– E of meridian= 20+ inches of rain
Interior LandformsInterior Landforms• Eastern Interior Plains: region most positively
affected by glaciers– Typically east of 100th Meridian
• 20-40 inches of rain
– Mostly flat w/ some rolling hills– Most fertile soil in world: Corn Belt
Interior LandformsInterior Landforms
• Interior Highlands– Ozarks:
Surface is limestone• Sinkholes,
caves, and springs
Canadian ShieldCanadian Shield
• Giant core of bedrock (millions of yrs. old)– Negatively affected by Glaciation:
scraped down to bare rock/thin soil• Good soil deposited in Great Plains
– Only veg. is forests in south
– Great for minerals (ores, gold, silver, copper, etc.)
Exposed Precambrian bedrock
Eastern MountainsEastern Mountains
• Appalachians: formed 300 million yrs ago– Oldest mts; eroded to 5,000-6,000 ft– Eastern NA plate collided with African plate– From Quebec to central Alabama– Valleys great for agriculture
Piedmont & LowlandsPiedmont & Lowlands
• Piedmont: E of Appalachians– Plateau region that drops (Fall line) into
the coastal lowlands
– Many 1st cities originated here: Philadelphia, Richmond, Baltimore, D.C…. WHY?• Rapids/waterfalls = hydroelectric power and
blocked from moving inland
LowlandsLowlands
• Atlantic Plain- Carolinas, narrower as move North
• Gulf Coastal Plain- west toward TX
WaterWater• US/Canada wealthy b/c of abundant water- power,
transportation
WaterWater• Mississippi: 2,350
miles– Starts as stream in
Minnesota– Gets to width of 1
½ miles & empties into Gulf of MX
– Affects all/part of 31 states and 2 provinces
– One of world’s busiest waterways
WaterWater• St. Lawrence River:
one of Can. most impt. Rivers– From Great Lakes to
Atlantic, forms country border
• Niagara Falls: – Tourist attraction, and
major source of hydroelectric power
– Form border of Ontario and NY
WaterWater
• Glacial Lakes– Great Bear Lake & Great Slave Lake
formed by glacial dams
– Great Lakes (Huron, Ontario, Michigan, Erie, Superior) formed by glacial gouges• St. Lawrence Seaway- series of canals & rivers• Helped build industry in NE
IslandsIslands
• NYC’s Manhattan Island: impt. economic center
• Hawaii: volcanic island state, big tourism
• Newfoundland, P.E.I., Vancouver I.: Canada’s most impt.
• Greenland: world’s largest island, Denmark territory (Alaska + TX)
ResourcesResources
• Fuels– petroleum & nat. gas: TX and Alaska, & Alberta
lead– Coal: Appalachians, Wyoming, & British
Columbia
• Minerals– Gold, silver, copper: Rockies– Iron & nickel: Canadian Shield
ResourcesResources
• Timber– Today cover <50% of Canada & 1/3 of US– Conservation of forests and animals is high priority
• Fishing– Grand Banks (Can.), Atlantic, Pacific, and Gulf of
MX• Cod fishing banned in Grand Banks in ’92 due to
overfishing