Canadian Landforms

Canada’s Landforms The Canadian Shield Highlands Lowlands Canada is made up of three distinct types of landforms: The Canadian Shield Highlands Lowlands

The Canadian Shield The Canadian Shield is a large geographic area in eastern and central Canada composed of bare rock dating to the Precambrian Era (about 2 billion years old) It is also called the Precambrian Shield, or Laurentian Shield. it covers approximately 8 million square kilometers. The Canadian Shield is made up of some of the planet's oldest rock, largely granite and gneiss It covers about half of Canada

How Did The Canadian Shield Form? from the eruptions of ancient volcano belts in the Precambrian era Over the years the area was eroded. Mountains have deep 'roots', and float on the denser mantle below. As mountains erode, their roots rise, and are slowly eroded as well. The rocks that now form the surface of the Canadian Shield were once far below the earth's surface. the last ice age, glaciers covered the area and scraped the rock clean as they moved

Who Houses The Canadian Shield? Manitoba Ontario Quebec Northwest Territories Nunavut Greenland Duluth (Minnesota) Wisconsin (Green Bay, St. Paul)

Major Cities Sudbury Timmins Thunder Bay Chicoutimi- Jonquiére

The Shield’s Topography The topography varies because of the vast area that it covers Boreal forest is the common vegetation. Flora in the Canadian Shield is more suited to the thin, sandy soil. There are some deciduous trees, which benefit the pulp and paper industry. There are no trees above tree-line due to the growing season being too short, lack of precipitation, and permafrost.

The Shield’s Topography Chaotic patterns of bodies of water Therefore, the major industries include pulp and paper, mining and hydro-electric plants The rocks in this region are old.The region is full of igneous rock, which later turned into metamorphic rock. The region is well above sea level, as it is in a very mountainous area.

The Shield’s Topography The rocks in this region are old.The region is full of igneous rock, which later turned into metamorphic rock. The region is well above sea level, as it is in a very mountainous area.

Igneous Rock Igneous rocks are formed from molten rock called magma. They are mostly crystalline (made up of interlocking crystals) and usually very hard to break.

Basalt Gabbro Pumice Granite

Metamorphic Rocks Metamorphic rocks were once igneous or sedimentary rocks, but have been changed (metamorphosed) as a result of intense heat and/or pressure within the Earth’s crust. They are crystalline and often have a squashed (foliated or banded) texture

Slate Schist Gneiss Marble

How were mineral deposits formed in the rock of the Shield? Minerals were present in magma beneath the earth’s crust As it rose toward the surface, it forced its way into cracks and cavities in the shield rock This took millions of years As it cooled, some minerals were deposited in the magma itself

Minerals Gold Nickel Copper Zinc Lead Diamonds

Mining companies are attracted to the Shield because of the presence of metallic minerals The mineral ores are smelted to remove waste materials

Formation of lakes, rivers, oceans • The action of glaciers - the scraping and gouging action of ice crated depressions in the bedrock • these depressions filled with water to form the hundreds of thousands of lakes • the sand, gravel, and clay deposited from the glaciers dammed up rivers • bodies of water were forced to flow in different directions and resulted in a very disorganized pattern of winding rivers, lakes, and swamps

Where does our water go? Canada’s Drainage Basins A drainage basin is an area that drains all precipitation received as a runoff or base flow (groundwater sources) into a particular river or set of rivers. Canada’s major drainage regions are: Atlantic Ocean Hudson Bay Arctic Ocean Pacific Ocean Gulf of Mexico

The Pacific Ocean Drainage The Pacific Ocean drainage area drains the area west of the Rocky Mountains. The Fraser, Yukon and Columbia rivers are the largest rivers draining this region.

The Arctic Ocean Drainage The Arctic Ocean drainage area is the area flowing directly into the Arctic Ocean or into the channels of the Arctic Islands. The Mackenzie River dominates the Arctic Ocean drainage area.

The Hudson Bay Drainage The Hudson Bay drainage area is a huge area that captures about 30% of total Canadian runoff. Many of its river systems such as the Nelson and Churchill River (of Manitoba) drain eastwards from the continental divide to Hudson Bay. As well, many large rivers drain from the south and east into Hudson Bay or James Bay. The extensive area of drainage into Ungava Bay is also considered to be part of the Hudson Bay drainage area.

The Atlantic Ocean Drainage The Atlantic Ocean drainage area is dominated by the Great Lakes-St. Lawrence system but there are other significant drainage basins such as those of the Churchill River (of Labrador) and the Saint John River in New Brunswick.

Gulf of Mexico Drainage Gulf of Mexico drainage area is a small portion of southern Alberta and Saskatchewan drains south into the Mississippi system which ultimately drains into the Gulf of Mexico