Structure of the Earth: The second layer in the Earths structure, which is 10-15km below oceanic crust and 35km below continental crust. It reaches a depth of 2,900km, has a density between 3.3-5.6kg/m3 and is made up of Iron and Magnesium
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Structure of the Earth: The third layer in Earths structure, at 2,200km thick and made up of liquid iron and Nickel, and has a temperature between 4,500 and 5,500 degrees C. This metal creates convection and Earths magnetic field
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Structure of the Earth: The final layer in the Earths structure which is 1,220km thick and has a temperature of 5,200 degrees C. It's a hot, dense ball of mainly Iron, but because the pressure is so high, the Iron is in solid state
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... are when heat comes from within the mantle. Hot rock rises and cold rock descends. Very slow motion in solid state transfers stresses to the lithosphere. Shallow ... moistens and cools atmosphere, whilst deep ... dries and warms atmosphere
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... is lateral movement of new oceanic crust away from a mid-ocean ridge. They are formed at constructive plate boundaries and is evidence to proove palaeomagnetism. The crust acts like a conveyor belt
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... is studies confirming sea flood spreading. The earths magnetic field changes every 400,000 years and particles called magnetite (formed form iron) record the earths magnetic orientation
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Age of ... investigates ocean sediments and crustal rocks in the deep ocean. Cores of 7000m were drilled and showed evidence for sea-floor spreading. The oldest sediment was found nearest continents and no rock is older than 200 million years old
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... evidence for continental drift: Rocks of the same age and type displaying same formations are found. Mountain trends are similar in Eastern USA and North West Europe. Similar glacial deposits are found in Antarctica, South America and India
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... evidence for continental drift: Similar fossil formations are found on either side of the Atlantic. Plant remains from the humid swamps that later formed coal deposits have been found in Antarctica and India
