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Earth can be divided into four different spheres, the geosphere , the hydrosphere ,

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the biosphere , and the atmosphere .

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In the next units we are going to study all of them, beginning with the geosphere.

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The geosphere is the sphere that contains the entire rocky structure of Earth.

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This means that it is formed by all the rocks and magma from the core to the surface.

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The geosphere can be divided in three layers.

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The crust is the Earth's outermost and thinnest layer.

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It is solid, composed of rocks and minerals.

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It can be oceanic, on the sea and ocean floors, with a thickness of about 6 km, or continental,

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on the continent, thicker, with a maximum thickness of 70 km in the largest mountain.

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The mantle.

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It is the largest layer.

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of the mantle is solid however a tiny section of the upper part is composed of molten rocks

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what we call magma finally the core it is the innermost layer it is made of dense materials

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mostly iron and nickel because during the formation of the planet the densest substances

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ended up in the deepest part of the planet.

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It is divided in an outer core, liquid,

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which is responsible for the magnetic field of the Earth,

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and an inner core that is solid due to the high levels of pressure.