Earth’s Layers

Read the passage about Earth's layers. Which of the following is NOT one of Earth's four main layers?

• Crust

• Mantle

• Atmosphere

• Inner Core

Read the passage about Earth's layers. Fill in the blank: Geologists study Earth's interior by collecting direct evidence using ________ and indirect evidence from seismic waves caused by earthquakes.

• rock samples

• water samples

• air samples

• plant samples

Which layer of Earth is the thickest according to the diagram?

Explain why no human or machine can physically observe the inside of Earth.

What is the mantle mostly made of?

• Basalt and granite

• Iron and magnesium

• Oxygen and silicon

• Water and gases

Read the passage carefully. Fill in the blank: The mantle is a layer of ______ rock directly below the crust.

• hot, solid

• cold, liquid

• soft, gaseous

• hard, metallic

Read the passage carefully. True or False: The lower mantle is less rigid than the upper mantle.

• True

• False

Explain how magma forms in the mantle and how it can lead to the formation of a volcano.

What is the composition of Earth's outer core?

• Solid iron and nickel

• Liquid iron and nickel

• Molten rock

• Water

Scientists think the movement of the liquids in the outer core creates Earth's ________ field.

• magnetic

• electric

• gravitational

• thermal