Science

^^Earth crust:^^

• $The outer layer of the earth.$
• $thinnest layer$
• Made up of both continental\n  (land)and oceanic crust(under\n  the ocean).
• $least dense$
• $Composed of mostly granite and basalt$

  @@Earth@@ @@Mantle:@@

• ^^Largest layer of the Earth^^
• ^^Composed of silicate rocks rich in   magnesium and iron^^
• Intense heat causes the rocks to rise   and then cool and sink.
• ^^The process is called convection,   which causes the crust to move.^^
• Average temperature 3000
• ^^Made up of mostly magma^^
• ^^Contains convection currents that move the tectonic plates^^

^^Earth^^ ^^outer^^ ^^core^^^^:^^

• $Liquid layer$ 2,300 km thick, second larges
• $Composed of liquid iron and nickel$
• $Lies between inner core and mantle$
• $Because the magma moves around the inner core, Earth’s magnetic field is created.$

Average temperature 4000o -5000o

%%Earth%% %%Innercore:%%

• ^^A solid ball of metal^^
• ^^Made of solid nickel and iron^^
• ^^Densest layer of the Earth^^
• Average temperature 5000-6000
• Spins at a speed faster than the Earth   rotates
• ^^So hot it melts everything in the outer   core^^
• ^^a soild^^

^^Seismic:^^

• Seismic waves are used to\n  determine which layers of the\n  Earth are solid or liquid.
• Some seismic waves cannot\n  pass through certain layers\n  giving us a clue to the layer’s\n  composition.

  ^^Oceanic Crust:^^

• A thin layer of crust that\n  overlies the ocean basins
• More dense than continental\n  crust
• Mostly basalt rock
• $Thinner than continental crust.$
• Younger (newer) than\n  continental crust

  $Continental Crust$

  ^^Continental Crust:^^

• Layer of rock which forms the\n  continents
• Less dense than oceanic crust
• Mostly granite
• Thicker than oceanic crust
• Older than oceanic crust