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# Continental Drift Theory The theory was proposed in 1912 by a meteorologist and a scientist named Alfred Wegener. The theory stated that all the continents were once joined together in a supercontinent called *Pangea*. ## Laurasia * A supercontinent - 250 million years ago - It is estimated th...

# Continental Drift Theory The theory was proposed in 1912 by a meteorologist and a scientist named Alfred Wegener. The theory stated that all the continents were once joined together in a supercontinent called *Pangea*. ## Laurasia * A supercontinent - 250 million years ago - It is estimated that the continents became separated, allowing the ocean to start forming the continents. The earth was surrounded by a supercontinent called *Pangaea*. ## Gondwana * A continent - 100 million years ago - The supercontinent broke into pieces. The northern piece, called *Laurasia*, and the southern piece called *Gondwana*, had split into smaller pieces. ## Evidences That Support Continental Drift 1. ***Apparent fit of the Continents*** - South America fits together, like a puzzle with Africa. - India, Madagascar, and Africa fit together in the same way. 2. ***Fossil Correlation*** - fossils and minerals of the same kind are found on the continents separated before. - Appalachian mountains - Scottish highlands 3. ***Magnetic Reversals*** - Magnetic patterns are found on the ocean floor, especially those near the Mid-Atlantic Ridge and Africa. - Also called *Paleomagnetism*, or a switch of plates. 4. ***Ocean basins*** - break up (seperation) of the continents. - **Mesosaurus:** - a saltwater reptile; found near South America and South Africa. - **Cynognathus:** - terrestrial reptile; found in both South America and Africa. - **Glossopteris:** - fern; found in all the continents. - **Trilobites:** - extinct marine arthropod; found in North America and Europe. All of the above explain information on the **Plate tectonic theory** - why the plates move.