geo 8.2

• Antarctica


  Made up of two geographic regions - East Antarctica and West Antarctica - separated by the Transantarctic Mountains
• Antarctica's climate


  • Extremely cold and dry
• East Antarctica


  Most of it is a shield, a very old part of the Earth's crust that is at least 500 million years old, formed when the supercontinent Pangea split apart
• Pangea splitting apart


  Broke into two continents during the Jurassic period: Laurasia in the north and Gondwana (or Gondwanaland) in the south
• Gondwana split apart


  About 160 million years ago
• West Antarctica


  Under its covering of ice, consists of the Antarctic Peninsula and a great many islands, a peninsula is an area of land that is almost surrounded by water and only connects to the mainland in one place
• In the past, the Antarctic Peninsula and the Andes Mountains were one long mountain range
• West Antarctic Rift System

  Starting in the Cretaceous period, East and West Antarctica started to move apart and formed faults, magma came to the surface and formed a new crust, creating a rift (or rift zone)
• Magma rises through the faults to the surface of the Earth and creates volcanoes like Mount Erebus
• The rift zone on the Ross ice plateau and Marie Byrd Land is currently covered with ice
• West Wind Drift


  Ocean currents have an influence on climates all over the world, the West Wind Drift is extremely cold, created when Australia separated from Antarctica, the water got colder and colder, an ice sheet formed on Antarctica that reflected a lot of sunlight, making it even colder