Geomorphology

• Geological time


  The number of years ago that rocks and landforms were made
• Molten


  Liquid (hot)
• Magma


  Molten rock
• Mantle


  The layer of the material around the earth's core
• Crust


  The outer layer of the earth, formed by solid rock
• Igneous rock


  Rock which forms when magma cools
• Lava


  Magma that comes out of the Earth's surface
• Crystalline


  Contains crystals of minerals
• Sedimentary rock


  Rock which forms from layers of compressed sediments
• Sediments


  Pieces of rock, clay and other substances from eroded rocks which accumulate at the bottom of a sea or lake
• Strata


  Layers of rock
• Fossil


  The remains of dead plants or animals which have been preserved in rock
• Metamorphic rock


  Rock which has been changed by heat or pressure or both
• Formation of the Earth


  1. The Earth was a fiery ball of gas and liquid

  2. Over the next few million years, the Earth began to cool

  3. Several layers separated inside the Earth

  4. Heavier metals like iron and nickel sank to the centre to form a metallic core
• Crust


  • A thin outer layer between 6 and 90 km thick formed of solid rock
  • The crust is thickest beneath the continents and thinner beneath the oceans
  • This layer is least dense
  • The crust is made up of mostly silicon, magnesium, iron and aluminium
• Mantle


  • About 2900 km thick
  • Rocks are in a hot, thick molten state
  • The molten rock, known as magma, has a plastic consistency that allows it to move and flow slowly
  • The mantle is denser than the crust and makes up 84% of the Earth's volume
  • Temperatures in the mantle range from 1000-2200°C
• Outer Core


  • About 2000 km thick, very dense, but still molten
• Inner Core


  • 1200 km thick, extremely hot
  • It is assumed by scientists that the inner core is an extremely dense, solid metallic ball made of mostly nickel and iron
  • It is around 5200°C
• Continental drift


  The theory that the continents were once one landmass, but have drifted apart over time
• Tectonic plate


  A section of Earth's crust which can move on the mantle
• Plate boundary


  The edge of a tectonic plate
• Convergent plate boundary


  A plate boundary where plates are moving towards each other
• Divergent plate boundary


  A plate boundary where plates are moving apart
• Transverse plate boundary


  A plate boundary where plates slide past each other
• Subduction zone


  A deep trench on the ocean floor where an oceanic plate is drawn under a plate boundary
• Destructive plate boundary


  A plate boundary where land is being destroyed
• Theory


  A carefully thought-out explanation for observations of the natural world that has been constructed using the scientific method
• Alfred Wegener had the idea and developed the continental drift theory


  1912
• Continental drift theory


  The theory that at one time the continents were all joined together
• Alfred Wegener noticed that all the modern day continents fit together like puzzle pieces and the idea that they were all once together was formed
• Pangea


  The combined landmass of all the continents joined together
• Pangea splitting


  1. Became Laurasia in the north and Gondwanaland in the south

  2. The land masses / continents slowly moved apart over the years

  3. Earth now consists of seven continents