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Theory of Continental Drift. Presented by Mr. D’Angelone. Who proposed the Theory of Continental Drift?. Alfred Wegener. German scientist 1880-1930 Proposed the Theory of Continental Drift Provided early evidence. What is Continental Drift?. Theory of Continental Drift.
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Theory of Continental Drift Presented by Mr. D’Angelone
Alfred Wegener • German scientist • 1880-1930 • Proposed the Theory of Continental Drift • Provided early evidence
Theory of Continental Drift • Wegener proposed that all the continents had once been joined together in a single landmass and have since drifted apart. • Pangaea was the name given to the super continent.
Evidence for Continental Drift • Early Evidence • Puzzle-like fit of the continents • Fossil clues • Climate clues • Glaciers • Glacial deposits • Rock clues
Puzzle-like fit of the Continents • The edges of some continents look as if they would fit together like a puzzle.
Fossil Clues: Mesosaurus • A freshwater swimming reptile • Fossils found in South America and Africa. • Wegener thought that this reptile lived on both continents when the continents were connected.
Fossil Clues: Glossopteris • Fossil Fern • Found in Africa, Australia, India, South America and Antarctica. • Wegener believed that all these areas were connected.
Climate Clues • Fossils of warm weather plants were found on islands in the Arctic Ocean. • Wegener believed that these islands drifted from tropical regions.
Climate Clues: Glacial Deposits • Glacial deposits and grooved bedrock found in southern areas of South America, Africa, India, and Australia. • Indicates that these continents were once covered with glaciers. • Wegener believed that these continents were covered with ice near Earth’s South Pole at one time.
Rock Clues • Similar rock structures are found on different continents. • Mountains found in the eastern U.S. are similar to those found in Greenland and western Europe. • The clues found in rocks, support the idea that continents were connected when these rock structures formed.
Scientists Reject Wegener’s Theory • Wegener provided more than evidence for his theory. • He attempted to explain how drift took place. • Unfortunately, Wegener could not provide a satisfactory explanation for the force that pushes or pulls the continents. • Therefore, scientists rejected his theory.