Cards (11)

    • Structure of the Earth

      Comprises of the crust, mantle, outer core and inner core
    • Crust and upper part of the mantle

      • Broken into tectonic plates
    • Continental drift (plate tectonics)

      Theory proposed by German scientist Alfred Wegener at the beginning of the last century
    • Before Wegener, it was thought that mountains formed because the Earth was cooling down and contracting
    • This process formed wrinkles, or mountains, on the Earth's crust
    • Mountains are not spread evenly over the Earth's surface
    • Wegener's theory

      Mountains formed when the edge of a drifting continent collided with another, causing it to crumple and fold
    • It took more than 50 years for Wegener's theory to be accepted
    • It was difficult to work out how whole continents could move
    • Evidence of convection currents within the mantle was discovered in the 1960s to support the theory fully
    • Evidence for continental drift

      • The match in shape between the east coast of South America and the west coast of Africa
      • Similar patterns of rocks on both sides of the Atlantic
      • Similar fossils on both sides of the Atlantic - including the fossil remains of land animals that would have been unable to swim across from one side to the other