Physical Geography of the U.S. & Canada Chapter 5 Section 1 - U.S. & Canada cover 7 million sq. miles - 12% of Earth Western 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—collision between Pacific and North American plates Western Features Great Valley California alluvial valley FERTILE area formed of sediments deposited by streams during flooding out produces any other region in fruit & vegetable production In Between Landforms Dry basins and plateaus fill area between Pacific Ranges and Rockies – Why? rain shadow effect from Pacific Ranges In Between Landforms Great Basin Region: area of low land surrounded by mts. Great Basin, Mojave, Sonoran, & Chihuahuan Deserts In Between Landforms Death Valley: hottest & lowest (282 ft. below sea level) place in N. Am. dancing rocks phenomenon In Between Landforms Columbia Plateau- Created by lava seeping thru cracks Aka: Flood basalt— eruptions lava coating landmass Eventually part of crust sank into space left by lava In Between Landforms Colorado Plateau- Created by tectonics and erosion (Colo. River) Grand Canyon @ southern end Walls as steep as 6,000 ft Hoover Dam Built on Colorado River b/w Arizona and Nevada (19311935) What is purpose of building dam? to provide irrigation, flood control, and hydroelectricpower Rocky 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 Divide Divide = high point or ridge that determines the direction that rivers flow E - toward Arctic Ocean & Atlantic Ocean W - into the Pacific Ocean Rivers Main rivers that have headwaters (source) in Rockies Colorado, Missouri Columbia, Rio Grande, Mackenzie, Interior Landforms US: between Rockies and Appalachian Canada: between Rockies and Canadian Shield Interior 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 High Plains: primarily W of the 100th meridian W of meridian= 10-20 inches of rain (semi-arid); good for rangeland Rain E shadow from Rockies of meridian= 20+ inches of rain Interior Landforms Eastern glaciers Interior Plains: region most positively affected by Typically east of 100th Meridian 20-40 inches of rain Mostly flat w/ some rolling hills Most fertile soil in world: Corn Belt Interior Landforms Interior Highlands Ozarks: Surface is limestone Sinkholes, caves, and springs Canadian 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 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 & 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 Lowlands Atlantic PlainCarolinas, narrower as move North Gulf Coastal Plain- west toward TX Water US/Canada wealthy b/c of abundant water- power, transportation Water Mississippi: miles 2,350 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 Water 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 Water 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 area allowed to industrialize quickly Islands 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) Resources Fuels petroleum & nat. gas: TX and Alaska, & Alberta lead Coal: Appalachians, Wyoming, & British Columbia Many Appalachian towns are now struggling because coal is becoming more expensive to use and is therefore being used less Minerals Gold, silver, copper: Rockies Iron & nickel: Canadian Shield Resources 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