|MadSci Network: Earth Sciences|
Hi Matt Yes, you are right. But the stuff at the center of the earth has all the weight of the stuff ABOVE it squashing it down. So the pressure is high - just like at the bottom of the sea. The whole earth was once molten, so any pressure was transmitted right down to its centre, where it is highest of all. It is so high the material (perhaps iron) is in a molten state never yet directly investigated by science [Note added by MadSci Admin: The study of seismic waves gives us SOME idea of what the interior of the Earth is like.] You might think that the earth's crust, like an eggshell, could support its own weight without pushing on stuff inside (lower down). But the crust is, in proportion, just about as thick as the skin on an apple. Its weight is negligible, it was not always there, and it is not strong enough even to support its own weight. John
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