Evidence for plate tectonics (Continental Crust)

Question 1

Parallel coastlines (jigsaw fit)

Answer 1

• Barthymetric charts (deep sea maps) show that continental shelf-edge fit together to aa high degree as they are not as susceptible to erosion as above water coasts.
• This is true of the Western African coast and Eastern South American coastlines which run parallel to each other and would form a neat junction if the South Atlantic Ocean did not exist between them.

Question 2

Distribution of Mountain Chains

Answer 2

• The distribution pattern of rock types and the mountain chains they form make sense when the separate land masses of contemporary continents are placed together.
• For example, mountains that formed during the Caledonian Epoch are now on opposite shores of the world’s ocean basins; in Greenland, Scandanavia, and North America for example.

Question 3

Land based fossil evidence

Answer 3

-Fossils of ancient mesosaur and gigantic glossopteris fauna have been found in similarly aged rocks across, Africa, Antarctica and South America. These organisms were not able to survive in salt water environments; their seperate existence therefore is unexplainable without continental drift.