Continental Drift

Science, Grade 6

Continental Drift

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Table Of Contents: Continental Drift

1. What Is the Continental Drift Theory?
In the early 1900s a scientist named Alfred Wegener proposed the continental drift theory, which suggests that the continents were once together as a single landmass that broke up and drifted apart over millions of years.
2. Basis of the Continental Drift Theory
Wegener based his theory on the observation that the boundaries of the continents appear to look like pieces of a large puzzle.
3. Evidence for Continental Drift
Studies of fossils and glacial striations in rocks on different continents also supported continental drift.
4. Pangaea
According to the continental drift theory, all of the continents once formed a large, single landmass called Pangaea. We now know that Pangaea existed 245 million years ago, when dinosaurs were roaming the Earth.
5. Laurasia and Gondwana
About 180 million years ago, Pangaea began to split into two smaller continents called Laurasia and Gondwana.
6. Modern Continents
Approximately 65 million years ago, these two landmasses had broken apart to form the modern continents.
7. Theory History
The continental drift theory was an accepted part of geology for about 50 years until it was replaced by the more complete theory of plate tectonics.