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Vocabulary on Crust, Mantle and the Core

1) Crust

The outer layer of rock that forms the Earth's skin.

It is a solid layer of rock that includes both dry land (continental crust) and the ocean floor (oceanic crust)

2) Mantle This layer is below the crust - It is made up of rock that is very hot but solid:
3) Lithosphere The upper part of the mantle and the crust form the lithosphere - a hard rigid layer
4) Asthenosphere Below the lithosphere - this is the layer that is softer and moves (like tar) It is semi-solid, but it is still hard - This layer has molten rock - magma
5) Lower Mantle Below the Asthenosphere - It is completely solid
6) Plasticity The ability to bend and flow - the Asthenosphere has this property even though it is said to be solid
7) Convection Currents The movement of material due to changes in temperature -
8) Mohorovicic Discontinuity The very thin layer separating the Mantle from the Crust
9) Gutenberg Discontinuity The very thin layer separating the Mantle from the Core
10) Core The core is made up of the metals iron and nickel

It has two parts: the Outer Core and Inner Core

11) What gives Earth its magnetic property? The metals in the core create the effect of a giant magnet running through Earth.  This creates a magnetic field in our atmosphere called the magnetosphere.  This is why all compasses point to the North pole - it is our giant magnet
12) What causes convection currents and how do they move Earth's plates?  Heat from the core makes the magma in the mantle rise - cooler material from Earth's surface makes the magma sink - This continuous circular movement is called convection currents.  This movement is constantly pushing on Earth's crust causing it to move and break.