EQ1:Pangea Flashcards
Who created the theory of Pangea?
Alfred Wegener
What was Alfred Wegner’s theory of contientl drift?
-He came up with the theory of Pangea in 1915 (a supercontinent he believed to have existed 335-175million years ago consisting of all of earth’s continents joined together as one
-he suggested biological, geological and climatological evidence to prove his theory but could not explain how plates moved so his theory was rejected
What biological evidence did Wegner have?
- Mesosaurus. Small reptile. Fossils and remains found in South Africa and Brazil.
- A plant which existed when coal was being formed has been found in India and Antarctica.
What geological evidence did Wegner have?
• Rocks of similar age, type, structure and formation found in South Africa and Brazil.
• Dovetailing, refers to the way the shapes of continents appear to fit together like pieces of a jigsaw puzzle.
Wegener noted that the coastlines of continents, particularly South America and Africa, seemed to align closely when placed together, suggesting that they were once part of a larger landmass
What climatological
evidence did Wegner have?
• Coal found under
Antarctic ice cap.
• Evidence of glaciation in
Brazil and India.
How could sea floor spreadng prove his theory?
-As the sea floor grows wider, the continents of opposite sides of the ridge move away from each other. The North American and Eurasian tectonic plates, for example, are separated by the Mid-Atlantic Ridge.
-The two continents are moving away from each other at the rate of about 2.5 centimetres (1 inch) per year.
How could paleomagnetism be proof of Werner’s theory?
• Paleomagnetism is the record of changes in the earth’s polarity (change in the magnetic poles) and it gave rise to this idea of sea-floor spreading
•The technology of seafloor mapping highlighted the earth’s depth of oceans and the small variations in the Earth’s magnetic field which showed a striped pattern across the ocean floor
