continental drift andie
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- Explain the force that moves the continents.
- Write todays date and EQ on page 77.
2. What is the evidence for continental drift? 3. Wegener 1880-1930 earthobservatory.nasa.gov
- Alfred Wegener first proposed the theory of continental drift.
- Continental driftwas Wegeners theory that all continents had once been joined together in a single landmass and have drifted apart since.
- Wegener named this supercontinentPangaea .
- Wegeners theory was rejected by scientists becausehe could not explain what force pushes or pulls continents.
Continental drift video clip Continentaldrift 5. Wegener searched and found three main pieces of evidence. Geologic - evidence in the layers of rocks across continents Fossil - evidence in the places certain fossils are found Climate - evidence in the changing climates during the past 6. Fit of Continents Across the Atlantic Mountain ranges in South America line up exactly with those in Africa! Geologic evidence 7. Fossil evidence Notice how fossils lined up across continents! http://evolution.berkeley.edu/evolibrary/images/history/fossils3.gif 8. Amazing Facts:Did you know......that India was once in the Southern Hemisphere connected to Antarctica? ...that North America was once surrounded by warm, tropical seas?...that Africa was once covered by glaciers, which were kilometers in thickness? ...that the Sahara desert was once a tropical rain forest? Climate change 9. As North America has drifted to different latitudes, changing climates were experienced.This shows the changes in the state of New Mexico. An example of the proof for changing climate: At one time, the area that is New Mexico was below the equator! 10. Wegener's problem He could not find the force that was causing the continents to drift. Because of this, he could not convince anyone that continents could move. He died in Greenland on an expedition.At the time of his death, no one believed his hypothesis! Technology developed during the 1940s changed all that!