C - Plate Tectonics - Wegener's theory

Question 1

What was Wegener’s Theory about? (2 words)

Answer 1

Continental drift

Question 2

What actually WAS Wegener’s theory of continental drift?

Answer 2

That about 300 million years ago there had been just one ‘super continent’ and the land mass broke into smaller chunks which are now our modern-day continents (we’re still drifting apart!)

Question 3

What was the evidence that Wegener found about continental drift?(3)

Answer 3

• The coastlines of Africa and South America seemed to match like the pieces of a jigsaw
• There were matching layers in the rocks in different continents
• Fossils were found in places where the present climate would clearly have killed them off

Question 4

Why wasn’t Wegener’s theory accepted for many years?

Answer 4

• Because his explanation about HOW the drifting happened wasn’t very convincing….

• People said it was impossible because the forces didn’t match up
• Wegener used inaccurate data in his calculations so he made some wild predictions about how fast they were moving
• He studied astronomy, not geology

Question 5

By the 1960’s, people were convinced that Wegener’s theory was correct. We now think that ‘continental drift’ is correct, and that the earths crust is made up of several chunks called _________ _______

Answer 5

Tectonic plates