Earth’s Interior• Geologists have only been able to drill to 3.8kilometers.• The center of the Earth is more than 6,000kilometers deep.

Since Geologists cannot observe the Earth’sinterior directly, they must rely on indirectmeasures.• Seismic Waves are recorded and study how theytravel through the medium of the Earth.•This information has shown that the Earth hasseveral Layers.

Earth’s Interior

Copy Picture

CrustCrust: the layer of rock thatforms Earth’s outer skin.• The crust includes rocks,mountains, soil and water.• The outer rind of rock ismuch 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.

MantleThe mantle is a layer of hot rock that extends nearly 3,000kilometers deep.• The Lithosphere is the upper portion of the mantle and thecrust.• It is approximately 100 kilometers deep and floats on topof 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 mantlebelow the Asthenosphere .

Earth’s Magnetic Field

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