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What was the first evidence that led people to think that the continents were once connected?
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The shapes of South America and Africa look like they could fit together.
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What did Alfred Wegener mean by "continental drift"?
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200 million years ago the supercontinent called "Pangaea" started to break up and the pieces drifted in different directions and moved to their present positions.
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"Pangaea" in english.
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All Land
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Name 4 proofs Wegener had to support his theory.
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1. He noticed that South America and Africa fit together like a jigsaw.2. On both continents he found fossils from the same plants and animals.3. On both sides of the Atlantic Ocean there are mountains similar in age..4. Continents had to be closer to the South Pole at one point because 250 million years ago there was ice covering parts of Southern Africa, India, Australia and South America.
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Why did scientists disagree with Wegener's theory?
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He couldn't explain/identify a force that was powerful enough to move the continents.
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Explain the theory of plate tectonics.
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There are about 20 plates that make up earth's outer shell. The plates float on a layer of hot rock, hundreds of kilometres below Earth's surface and they are mostly made up of both continental and oceanic crust. No one knows how they move but they think it's caused by the unequal distribution of heat within earth's core.
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Why are most earthquakes and volcanoes located near plate boundaries?
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The massive plates shake, creating earthquakes and the closer you are to the plate boundaries the more you feel it.
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How has the movement of Earth's plates shaped Canada?
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The mountain chains on the east and east coasts were formed as a result of plates bumping together.
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What formed when Canada's land mass was located in a warmer, tropical climate?
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Oil, gas and coal.
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