Chemistry - Ever changing Earth

• Layer 1 - The crust

  The thinnest layer of the earth
• Layer 2 - The mantle

  Slowly moving solid and liquid rock. Nearer to the core is hotter and a slow moving liquid. Nearer to the surface is cooler and a solid
• Layer 3 - The outer core


  Molten layer, composed of liquid iron, nickel, sulfur and oxygen. Between 4,000-6,000 degrees celsius
• Layer 4 - The Inner core 


  Solid metal that contains iron and nickel. Between 5,000-6,000 degrees celsius
• What is the earths Lithosphere?

  The solid outermost part of the Earth consisting of the earths crust and upper part of the mantle. Above the lithosphere is the atmosphere which contains the gases surrounding the earth
• Tectonic Plate theory pt.1

  • The earths lithosphere is divided into separate parts known as tectonic plates that move over the mantle at a rate of a few cm per year (continental drift).
  • The continental drift is due to convection currents in the earths mantle created by the difference in temperature between the inner core and the surface of the earth, causing slow movement of the mantle that shifts the plates resting on it
• Tectonic plate theory pt2 (Alfred Wegener)

  • The theory was first proposed by Alfred Wegener. He thought that the continents used to be joined together in a supercontinent called Pangaea and that the earths crust and upper mantle was made of sections that drifted apart over millions of years
  • Evidence for this was fossils from same species found on different continents and the pattern of rock formation is similar on both sides of the Atlantic