2. Earth’s Interior
• Geologists have only been able to drill to 3.8
kilometers.
• The center of the Earth is more than 6,000
kilometers deep.
Since Geologists cannot observe the Earth’s
interior directly, they must rely on indirect
measures.
• Seismic Waves are recorded and study how they
travel through the medium of the Earth.
•This information has shown that the Earth has
several layers.

4. Crust
Crust: the layer of rock that
forms Earth’s outer skin.
• The crust includes rocks,
mountains, soil, and water.
• The outer rind of rock is
much thinner than what is
beneath it.
• The crust includes both dry land and the ocean floor.
• It is thinnest beneath the ocean and thickest under
mountains.
•The crust can range from 5-40 kilometers.
•Oceanic crust is made up of basalt.
•Continental crust is made up of granite.

5. Mantle
The mantle is a layer of hot rock that extends nearly 3,000
kilometers deep.
• The Lithosphere is the upper portion of the mantle and the
crust.
• It is approximately 100 kilometers deep and floats on top
of the Asthenosphere .
•The Asthenosphere is a soft layer of the mantle.
•This layer flows slowly.
•The Asthenosphere is approximately 350 kilometers deep.
•The Mesosphere is the solid lower part of the mantle
below the Asthenosphere .

6. Earth’s Magnetic Field
• Currents in the liquid outer core force
the solid inner core to spin (planet w/in
another).
•The inner core spins slightly faster
than the rest of the planet.
•This movement creates the Earth’s
magnetic field.

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8. Earth’s Interior
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