What do you know about plate tectonics?

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The Earth has main layers: an outer layer called the ; a middle layer called the ; and an inner layer called the .

The core consists of two layers: an inner core, the centre of the Earth, which is made up of iron and nickle; and an outer core made of nickle and rock.

The mantle is the section of the Earth and is made up of semi-solid rock called .

The crust is the layer of the Earth and is made up of a hard rock .

The Earth's surface is broken into huge slabs of rock called plates, which float upon the . There are major ones and smaller ones. There are two types of plates: plates which form the land and are old, thick and , and oceanic plates which are and can be pushed down into the .

Heat rises and falls in the mantle causing currents. These are called currents and they cause the plates to .

The point at which two plates meet is called a plate . At a or boundary, two plates slide past each other, in different directions or different speeds. The most dangerous hazard is . An example of this type of boundary is the .

At a or boundary, two plates move apart from each other and erupts at the surface as . This often occurs under the sea where millions of years of eruptions have formed . An example of this type of boundary is the .

At a or boundary, two plates move towards each other, which can result in the plate sinking below the plate and into the mantle. This is known as . As the plate is pushed down, it melts and forms which slowly rises to the surface. Explosive can sometimes form as the magma rises through cracks in the crust. Powerful can occur due to sudden movement of the plates. The movement of the plates can push the crust up to form . An example of this type of boundary is the .