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Continental Drift - PowerPoint 2

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					The Theory of Continental Drift

Continental Drift Theory
• Proposed by Alfred Wegener in 1912 • 250 million years ago, all of the continents were combined into one super-continent called “Pangaea” • The continents gradually drifted apart to where they are today

Evidence to Support the Theory

“Puzzle Pieces”
• Continents look like they could be part of a giant jigsaw puzzle

Distribution of Fossils
• Plant and animal fossils found on the coastlines of different continents

Sequence of Rocks
• Same rock patterns found in South America, India, Africa, Antarctica and Australia

Ancient Climates
• Tropical plant remains (coal deposits) found in Antarctica • Glaciation in Africa, South America, India, and Australia during the same time

Problems With The Theory
• No mechanism for movement of continents • Wind and currents could possibly move fossils • Theory was not accepted by scientists


				
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