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5 Cards in this Set
- Front
- Back
- 3rd side (hint)
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The Crust |
Continental - 35-75km - less dense, older rocks (granite) - aluminium and silicon (Sial) - 1500+ mill years old - protrudes above the ocean, forming a continent
Oceanic - 6-10km - dense, younger rocks (basaltic) - magnesium and silicon (Sima) - under 200mill years old - younger than continental as dense rocks get forced into magma and melt --> forms again when plates move apart and magma comes up through the cleft |
- thickness of layer - density - type and age of rocks |
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Lithosphere |
- 80-90km - crust and upper mantle (solid rock) - where tectonic plates form |
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Mantle |
- 2900km - semi-solid molten rock (magma) --> mainly silicate rocks - great heat and pressure --> thick liquid state --> gets denser with depth |
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Asthenosphere |
- layer of softer, almost plastic-like rock in the upper mantle - can move very slowly, carrying the lithosphere on top - density increases with depth |
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Core |
- 5000+C - 4x denser than the crust - thought that as earth rotates, liquid outer core spins creating the earth's EM field
Outer core - 2300km - semi liquid - mostly iron
Inner core - 1200km - solid - iron and nickel alloy |
- thickness of layer - state - elements |
