Earth’s Interior

Anywhere on Earth… You may observe larger and smaller features on Earth’s surface called landforms. You may observe landforms that change slowly over time.

Inquiry Question: How might landforms change slowly over time?

Think of your own body… You cannot see most of what happens in your body because it is inside you. When you are sick, you may look ill. The Earth’s surface changes slowly over time because of processes under the surface…

If we want to know how the Earth changes on the outside, we should know what happens on the inside… Earth has three major layers…

Core The extremely hot and dense center of the Earth. At the very center it is most likely solid iron due to pressure.

Mantle The hot and large middle layer of the Earth. Kept in motion by heat, energy, and gravity. Made up of molten rock and metals.

Mantle Hot molten rock in the mantle that acts much like a liquid is called magma. Magma can escape the mantle and reach the Earth’s surface as lava.

Crust The outermost thin layer of the Earth made of rock Includes the continents and oceans Divided into sections called tectonic plates that “float” on the mantle.

Crust The places where plates meet are called faults. The San Andreas Fault is in California. When plates move, changes are made to the crust over time.

Mid-ocean ridges, trenches, and mountains are all formed because of movement of tectonic plates.

Crust Mantle Core

Inquiry Question for next time: How might the Earth’s inside change the outside?