Plate Tectonics Theory and Evidence

Wegener

• In the 17th century people began to notice that South America and Africa looked like they could fit together, like a jigsaw
• People thought that the continents might have been joined together before they started drifting apart
• 1912 - Wegener proposes the theory of continental drift
• He suggested that all the continents were joined together as a super continent called Pangaea
• Theory was based off of geological evidence and fossil records, but he couldn't back it up with a mechanism that explained how the continents moved
• 1950s - palaeomagnetism supported continental drift
• 1960s - sea-floor spreading provided the mechanism
• The theory became developed by more scientists and became known as the theory of plate tectonics

Geology

• South America and Africa have rocks of the same age and composition - when fitted together the distribution matches up
• The age, rock type, and distribution of some mountain ranges matches up in Scotland, Norway, Sweden and Finland matches up to the coast of North America
• These rocks will have been formed under the same conditions in the same place – only…