Unit 1AAnatomy of the Earth

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Core

1000 miles an hour

Core Inner Core:

Solid

Up to 4700 C

Iron, Nickel

Dense

Outer Core

Molten iron

3500-4000C

Dense

Mantle• Silicates and Magnesium Oxide

• Dense

• 1000-3500 C (hotter towards the core)

• Mostly solid, but rocks flow under pressure-viscous

• Giant convection currents carry heat from the core to the crust, ...

• ..and return cooler material towards core

• Thin layer of near-molten rock near crust

• Moho is the boundary between crust and mantle

Oceanic or Continental Crust?Of the two,

• Which is thicker?

• Which is more dense?

• Which is older?

• Which has greater complexity of rock types?

• Which gets recycled?

The Crust

• “ A brittle, fractured,

• thin, solid layer”

Crust