Earth Flashcards
What is the outer layer of the Earth? What are its properties?
The crust. It is a solid.
What is the next layer in after the crust? What are its properties?
The mantle. It is a solid, although it flows.
What is the next layer in after the mantle? What are its properties?
The outer core. It is a liquid.
What is the next layer in after the outer core? What are its properties?
The inner core. It is a solid composed of iron and nickel, and causes the magnetic field by moving around really quickly.
What was Wegener’s theory?
Continental drift - that at one point all the continents were joined together, but gradually moved apart over millions of years.
What evidence did Wegener have for his theory? (3)
The same type of fossilised plants and animals could be found in South America and Africa
The shape of the east coast of South America fits the west coast of Africa, like pieces in a jigsaw puzzle
Matching rock formations and mountain chains are found in South America and Africa
Why was Wegener’s theory not accepted by the majority of scientists? (3)
He was much younger than most respected scientists
He was not a trained geologist
He could not explain HOW the continents moved
How did the plates move in continental drift?
Convection currents in the mantle, caused by radioactive waste and the heat of the core.
