Convection Currents

Matter heats up, becomes less dense and rises.

Matter cools down, becomes more dense and sinks.

Looks like Magma! Add a little (internal) heat... ... and watch convection!
hot less dense, magma rises... ...plates move apart... ...a diverging boundary !
The Plates above this convection current would move apart!
Cool more dense, magma sinks... ...plates come together... ...a converging boundary !
The Plates between these convection currents would move together!
The asthenosphere is liquid, the lithoshpere is solid plates and internal heat causes convection!
Magma rises between South American & African
South America & Africa plates drift apart! (diverge)

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