LANDFORM CONNECTIONS How did earth become what we

LANDFORM CONNECTIONS

How did earth become what we know it as today? ? ?

PLATE TECTONICS � In 1915, Alfred Wegener said that the only possible answer was continental drift � About 300 million years ago all of the earth’s land masses collided to form one supercontinent � � � PANGAEA – “all land” Not until 1960’s!!! That technology existed to further develop Wegener’s theory…. now called plate tectonics State the four pieces of proof that WEGENER used for is theory of continental drift (pg 91):

Plate Tectonics � � Earth’s outer shell is made up of about twenty plates Moving over a layer of hot rock How far? ? below the earth’s surface? (90)______ It is possible that the unequal distribution of heat within the earth causes ________________

Precambrian Era � � � Longest era The earth was formed 4 600 000 years ago (pg 95)Many cycles of _______ and _______ took place during this era

Paleozoic Era � � � During this era Canada’s landforms continued to take shape (97) Geologists believe: The gas and oil in western Canada are a result of: The coal rocks of nova Scotia are from: How were the Appalachians formed?

Mesozoic Era � � � Lasted 180 million years How did the Coast Range Mountains form? How did the Rocky Mountains form? What roamed through the swamps and forests of the much warmer Canada back then? The end of the Mesozoic era was marked by another mass extinction More than half of all plant and animal species, including the dinosaurs became extinct

Cenozoic Era � � � How were Rockies finally formed? What was the Interior Plains formed from? The ice age occurred during the last two million years Huge masses of ice, or _______, developed as a result of a slight cooling of the earth’s climate What effects did the glaciers have on the Appalachians?

LANDFORM REGIONS

The Canadian Shield � � � Relatively flat with rounded hills of rock which are actually the roots of ancient mountains Rock contains valuable minerals Lead, gold, nickel copper, zinc

How did mineral deposits formed in the rock of the Shield? � � � Minerals were present in magma (beneath earth’s crust) As magma rose toward the surface, it forced its way into cracks and cavities in the shield rock Took thousands of years!! As the minerals slowly cooled, they separated into layers according to their density (104) Why is the shield ill-suited to farming but well-suited to mining?

The Lowlands � Consists of: � Interior Plains � Great Lakes-St. Lawrence Lowlands � Hudson Bay-Arctic Lowlands � � � (106) What covered the Interior Plains and how did the oil and gas form? Define escarpment The Great Lakes are located in basins that were gouged out by glaciers

� The arctic lowlands has a harsh climate which does not allow farming and the ground remains frozen most of the year

Highlands � Composed of � Appalachian Mountains � Innuitians � Western � � � Cordillera (111) How were the Appalachians formed and how were they later eroded? Why are the innuitians taller than the Appalachians? What two plates are responsible for creating the Western Cordillera and how were these mountain ranges created?

Tomorrow: Climate!!!