• Question: why did continental drift happen

    Asked by bronaghd to Angela, Gabriele, Karen, Shane on 20 Nov 2013.
    • Photo: Shane Mc Guinness

      Shane Mc Guinness answered on 20 Nov 2013:

      Great question again Bronagh,
      So, the surface of the earth is covered in a very thin layer of solid rock called the crust, floating on top of a very deep sea of melted rock or magma. However, it has been broken up into lots of large pieces which are all floating and bumping into each other constantly. Some believe that a large object hitting the earth first caused these cracks and started continental drift. Then, the movement of the magma under these, trying to push up through the cracks, causes their movement!

    • Photo: Karen McCarthy

      Karen McCarthy answered on 20 Nov 2013:

      Continental drift has also played a huge role in the evolution of life on Earth – would we have such diverse species for example if the continents stayed together? We might have ended up with tarantulas in Ireland instead of Australia!

    • Photo: Angela Stevenson

      Angela Stevenson answered on 20 Nov 2013:

      Ohhh that’s an interesting question! The continents were once connected into one gigantic supercontinent (200 million years ago it was called Pangaea), which started to break up into two smaller supercontinents, called Laurasia and Gondwanaland, during the Jurassic period. By the end of the Cretaceous period, the continents were separated into land masses that looked like our continents today. How did they manage to drift around like that? Continental drift is a result of the Earth’s crust slowly drifting atop of it’s liquid core. The Earth’s crust is divided into huge, thick plates that drift atop the soft mantle. The plates are made of thick rock that move both horizontally and vertically. Over long periods of time, the plates also change in size as their margins are added to, crushed together, or pushed back into the Earth’s mantle. It’s this that caused movement of the continents to the way they are positioned today 🙂 Hope that helps answer your question! Well done with all your questions Bronagh 🙂