Continental Drift Theory Alfred Wegner and Continental Drift

Continental Drift Theory

Alfred Wegner and Continental Drift Theory • Alfred Wegner was a German meteorologist & geophysicist who developed the first theory of continental drift. • Continental Drift is the gradual movement of the continents across the earth’s surface. meteorology: study of weather geophysics: study of the physics of earth.

Wegner’s Evidence • He used 3 pieces of evidence to develop his theory: – The continents fit together like puzzle pieces – The same fossils were found where the pieces fit together – Similar landforms were found on the different continents

Alfred Wegener Observed • He observed that South America and Africa fit together like puzzle pieces.

Alfred Wegener Researched • As he began to conduct research he found that Brazil and Africa had fossils of extinct animals that were the same!

Rock Formations • The rock layers that form the Appalachian mountains of the eastern U. S. matched quite well with those in Scotland. • Strata rock formations that make up the Santa Catarina system in Brazil matched those that form the Karro system in South Africa.

Plant Fossils, too • He found extinct plants had left their fossils in both Africa and Brazil. • He also found that rocks in Alaska contain fossil palm tree leaves, though there have not been palm trees at that latitude for a very long time!

Tropical Plants in the Arctic • Wegener found that tropical plants such a ferns that grow in areas around the equator had left fossils on an island in the arctic which is near the North Pole.

Wegener Posed Questions • How could rocks be exactly the same in Brazil and Africa? • How could fossils be exactly the same in Brazil and Africa? • How could tropical fossils be found at the North Pole?

Wegener Inferred • Alfred Wegener proposed that the continents must move. • He thought that at one time the continents must have all been connected in one big super continent. • He called that super continent Pangaea