Objective: To learn how tectonic plates move and what evidence we have for continental drift. Tectonic Plates. Starter: Word search – rock cycle review. Tectonic plates. The crust is made of about twelve plates . These are like big rafts floating on the semi-molten mantle.
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NB: The crystals will stain yourclothes and fingers
Millions ofyearsContinental Drift
People once thought that the oceans and the continents were formed by shrinkage from when the Earth cooled down after being formed.
Alfred Wegener proposed something different:
These continents look like they “fit” together. They also have similar rock patterns and fossil records. These two pieces of evidence led me to believe that there was once a single land mass.
Similar rocks and fossilsEvidence for Continental Drift
The theory is supported by several pieces of evidence.
For example, if we consider Africa and South America there is:
The middle layer is called the . . . . .
The middle layer . . . . .
has convection currents which move very slowly.
is made of solid rock which cannot flow.
is made up of metamorphic rocks.
is made up of sedimentary rocks.
The inner part of the inner layer (core) is . . . . .
liquid and made from aluminum and silicon.
liquid and made from iron and nickel.
solid and made from aluminum and silicon.
solid and made from iron and nickel.