About Lesson
B.7. Continental Drift Theory
- Given by Alfred Wegener in 1912.
- All continents formed a single continental mass(PANGEA), a mega ocean(PANTHALASSA) surrounded by the same.
- Around 200 million years ago, the supercontinent broke into two large land masses s Laurasia and Gondwanaland.
- Subsequently, These landmasses continued to break into various smaller continents that exist today.
- Evidence includes The matching of continents (Jigsaw fit), Rock of the same age across the oceans, Tillite, Placer deposits etc.
- Force for drifting – Pole – fleeing force due to rotation of the earth and tidal force due to the attraction of the Sun and Moon.
- Scholars rejected this theory because they considered these forces to be totally inadequate.