Plate Tectonics Flashcards
What are the four main points of the teory of plate tectonics?
The earths face is made up of a series of large plates, which are in constant motion
The ocean floors are continuously moving, causing it to spread from some plate boundaries and sinking at others
The movement is caused by convection currents
Who developed the theory of continental drift and plate tectonics?
Alfred wegener
What are the four points of wegener’s theory?
The earths continents fit together like a jigsaw
There are similar rock formations on either side of the atlantic ocean
Similar fossils were found on different continents
Fossils were found in abnormal places
Why wasn’t wegener’s theory accepted?
Because he couldn’t suggest any mechanism that could have moved the continents
What new pieces of evidence to back up wegener’s theory are there?
On the ocean floor canyons had been discovered
Samples were taken from the atlantic ocean. The middle of the atlantic was younger than the eastern or western edges.
They found rocks on land that was considerably much older than others.
